CROSS-REFERENCE TO RELATED APPLICATIONSThis application is a continuation in part of Biological Passageway Occlusion Removal, application Ser. No. 10/747,813 filed 29 Dec. 2003 attorney docket number GTEC 1001-4, which is a continuation in part of Tissue Removal Device and Method, application Ser. No. 09/819,350 Filed 28 Mar. 2001, which is a continuation of Biological Passageway Occlusion Removal, application Ser. No. 09/189,574 Filed 11 Nov. 1998, now U.S. Pat. No. 6,238,412 issued May 29, 2001, which claims the priority of U.S. Provisional Application Ser. No. 60/065,118, filed on Nov. 12, 1997;
This application is a continuation in part of Body Passageway Occluder and Method, application Ser. No. 10/765,564 filed 27 Jan. 2004, attorney docket number GTEC 1001-5, which is a continuation of Tissue Removal Device and Method, application Ser. No. 09/819,350 filed 28 Mar. 2001, which is a continuation of Biological Passageway Occlusion Removal, application Ser. No. 09/189,574 filed 11 Nov. 1998, now U.S. Pat. No. 6,238,412 issued May 29, 2001, which claims the priority of U.S. Provisional Application Ser. No. 60/065,118, filed on Nov. 12, 1997, the disclosures of which are incorporated by reference.
This application is a continuation in part of Medical Device and Method U.S. patent application Ser. No. 10/824,779 entitled Medical Device and Method, filed 15 Apr. 2004, attorney docket number GTEC 1002-1, which is a continuation in part of U.S. patent application Ser. No. 10/765,564 filed Jan. 27, 2004 which is a continuation of U.S. patent application Ser. No. 09/819,350, now U.S. Pat. No. 6,699,260, filed Mar. 28, 2001, which is a continuation of U.S. patent application Ser. No. 09/189,574, now U.S. Pat. No. 6,238,412, filed Nov. 11, 1998, and claiming the benefit of provisional Patent Application No. 60/065,118 filed Nov. 12, 1997. U.S. patent application Ser. No. 10/824,779 also claims the benefit of provisional Patent Application No. 60/463,203 entitled Anastomotic Apparatus and Methods for Use, filed on Apr. 16, 2003 and provisional Patent Application No. 60/496,811 entitled Thermoplastic Manufacturing Apparatus and Methods for Use, filed on Aug. 21, 2003. The full disclosures of each are incorporated herein by reference.
BACKGROUND OF THE INVENTIONThe present invention relates to medical devices and methods.
One aspect of this invention relates to a removal device for a biological occlusion and more particularly to a catheter and occlusion engaging element which is adapted to the removal of blockages in hemodialysis grafts. There are many techniques and devices known in the art for removing blockages in the vascular system and other passageways of the human body.
Another aspect of the present invention is directed to procedures, including biopsy and tumorectomy methods, and associated apparatus which provide for less invasive techniques while also providing for enhanced tissue specimens being retrieved.
Another aspect of the present invention relates to improved guide wires or catheters and method for their use, where the devices have a distal mechanism that acts as a mechanism for: 1. Flow Directed, using the natural flowing fluids, pressure differentials or contractile forces of the body onto the distal mechanism to direct its motion and direction or 2. Anchored, so that once the device is in the desired location, it can be anchored against the tissue where it rests; 3. Tensioned, so that placement of a device, over the guide wire is accomplished with less difficulty and 4. Occluded, so that vessels and aneurysms can be occluded.
Guide wire management in the operating room is problematic, and threading the needle of the arteries or other vessels including, but not limited to veins, intestines, fallopian tubes, etc. to reach the area to be treated is difficult. Further, once the guide is in the desired location, it is often difficult to make certain that the it remains in that location. Even further, once the guide wire, catheter, endoscope or other device is in the desired location and another device is placed over, through or along side it, the initially placed device has a tendency to move due to the forces exerted on it when other devices are using it as a guide.
Additionally, other anchors are required for attaching tissue or other matter to improved or different locations within the body.
Even further, vessel occluders are often required for a variety of medical procedures.
For these reasons, it is desirable to provide an improved devices and methods for their use, which facilitate1. using the physiologic motions of the body to help direct the device. In addition, flow pressure differential can be artificially created or enhanced by the technician/physician so that this same technology can be used when physiologic means is unavailable or insufficient. Further, the natural contractile forces of the body (e.g. those of the intestinal tract, gall bladder, esophagus, etc.) can be harnessed so that the device including, but not limited to guide wires, catheters, endoscopes, etc. are moved along with those forces. 2. Even further, it is desirable to provide a device that has an anchoring mechanism on it so that it will not move once in its desired position. 3. And yet even another desired characteristic would be to provide an anchored device that has a tensioning characteristic applied to it for placement of other devices over through or along side the first placed device. 4. And finally, another desired characteristic is that of a simple and effective occlusion system.
In general, this invention relates to a removal device for a biological occlusion and more particularly to a catheter and occlusion engaging element which is adapted to the removal of blockages in hemodialysis grafts.
There are many techniques and devices known in the art for removing blockages in the vascular system and other passageways of the human body.
There is a continuing need for improved devices to meet at least the following objectives.
The first objective is to reduce cost. This is particularly important in recent years where it is clear for safety and sanitary reasons that these will be single use devices. A device, even though it performs a function in some improved manner, will not be widely used if it is considerably more costly than the alternatives available.
A second objective is to provide a device that is simple to use and in a very real sense simple to understand. This will encourage its adoption and use by medical personnel. It will also tend to keep cost low.
The third objective is to provide a device that entails a procedure with which the medical profession is familiar so that the skills that have been learned from previous experience will continue to have applicability.
A fourth objective relates to the effectiveness and thoroughness with which the device performs, such as blockage removal or anastomotic device placement. For example, it is important that a maximum amount of the blockage be removed; recognizing that no device is likely to provide one hundred percent removal. With regard to bypassing or re-joining, it is important that an optimum amount of the tissue be removed and therefore replaced; recognizing that no device is likely to provide one hundred percent optimization.
A fifth objective concerns safety; a matter which is often so critical as to trump the other considerations. It is important to avoid tissue trauma. In many circumstances, it is critically important to avoid breaking up a blockage in a fashion that leads to flushing elements of the blockage throughout the body involved. In the case of using an anastomotic device in the tubular channels of the body, it is critically that the joining of the anastomosis does so while minimizing tissue trauma. Often this trauma is not realized immediately after surgery. Even further, leakage must be kept near zero.
There are trade-offs in design considerations to achieve the above five interrelated objectives. Extreme simplicity and a very simple procedure might over compromise safety. Addressing all of these considerations calls for some trade-off between the objectives.
Accordingly, an object of this invention is to provide an improved removal device for a body passageway blockage which achieves the objectives of reduced cost, enhanced simplicity, a standard procedure, high effectiveness and a high degree of safety. Most particularly, it is an object of this invention to achieve these objectives with an enhanced trade-off value for the combined objectives.
Another object of this invention is to provide an improved occlusion, tensioning, anchoring and flow device that achieves the objectives of reduced cost, enhanced simplicity, a standard procedure, high effectiveness and a high degree of safety. Most particularly, it is an object of this invention to achieve these objectives with an enhanced trade-off value for the combined objectives.
For these reasons, it is desirable to provide an improved device that may circumvent some of the problems associated with previous techniques. This improved medical device provides a new configuration that will eliminate some of those problems and methods for their use, which facilitate removal of vascular obstructions in the operating room or interventional suite.
Occlusive vascular disease is a common ailment in people resulting in enormous costs to the health care system. Blood clots and their accompanying plaque buildup are the most common type of occlusion. Removal of this disease from the body has been studied for several years and many techniques (devices and methods) have been studied and practiced. Sometimes the diseased/stenosed areas of the vessels may be removed by use of Embolectomy, Atherectomy, thrombolysis, etc. or angioplasty and/or stenting can repair the diseased vessel but all of these are not always effective. The deposit of sinuous plaque (arteriosclerosis) to the inner wall of arteries usually precedes clot formation. Several expensive devices (dilatation balloons, stents, mechanical cutters, etc.) have been introduced to fight this vascular occlusive disease, but none of which has proven to be the ‘magic bullet’ to treat this ubiquitous disease. Even when effective, these technologies often are effective for a short period of time. Because of the various problems with all of the techniques and approaches to solving this medical condition, there exists no particular method or device that is considered the most accepted mode of treatment.
Unfortunately, cancer too is a common ailment resulting in over 1,500 deaths every day in the U.S. (550,000 every year; the number two killer in the U.S. after vascular disease). Therapy modalities for cancer are plentiful and continued to be researched with vigor. Still, the preferred treatment continues to be physical removal of the cancer. When applicable, surgical removal is preferred (breast, colon, brain, lung, kidney, etc.). Often these cancers occur in the body channels that are actually not dissimilar to occlusions in the vasculature.
Even though there are many techniques and devices known in the art for removing blockages in the tubular channels of the body and/or for bypassing them with autogenous or synthetic means (both surgically and via a percutaneous, less invasive technique) and other passageways of the human body as well as removing other diseased tissue, there is a need to removed the diseased tissue and re-join healthy pieces of the tissue once the diseased tissue has been removed. This removed tissue may be removed because of many reasons some of which are (but certainly not limited to) cancerous or potentially cancerous material, vascular disease (or potential vascular disease), trauma to tissue, congenital disease of the tissue, etc.
SUMMARY OF THE INVENTIONAn aspect of the invention is directed to a vessel-occluding medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body. The catheter has a proximal catheter end and a distal catheter end and defines a lumen extending from the distal catheter end towards the proximal catheter end. The catheter is adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body. An expandable and contractible, vessel-occluding element is positionable near the distal catheter end and is placeable in radially expanded and contracted states. The expandable and contractible, vessel-occluding element comprises a braided element and a membrane contacting the braided element so that the braided element is substantially impermeable when in the radially expanded state. The expandable and contractible element has a funnel-shaped surface, when in the radially expanded state, and a longitudinally-extending opening to permit material to pass therethrough for receipt of material. A vessel-occluding assembly is housed at least partially within and is axially slidable through the lumen. The vessel-occluding assembly comprises an elongate support element, having a distal end portion, and a second expandable and contractible, fully-vessel-occluding element at the distal end portion. The second expandable and contractible, fully-vessel-occluding element is positionable at, is extendable from the catheter distal end, and is placeable in a collapsed and expanded, fully-vessel-occluding states.
Another aspect of the invention is directed to method of deploying an occluder in a body passageway. The method includes the following. A catheter is inserted into a body passageway, said catheter having a balloon-less blood flow blocking element affixed to the catheter. The balloon-less blood flow blocking element comprises a blood flow blocking surface with structural members which define openings therebetween. The blood flow blocking element is provided in a radially compressed state during the inserting step. The blood flow blocking element is radially expanded into a radially expanded, passageway sealing state extending to the wall of the body passageway after the inserting step. The radially expanding step is carried out without inflating a balloon using a fluid. The radially expanding step includes providing said blood flow blocking element in said radially expanded, passageway sealing state with an outer, distally facing, generally funnel surface extending out from said distal end of said catheter. The generally funnel surface is the blood flow blocking surface. The radially expanded, passageway sealing state of said blood flow blocking element is used for completely blocking passage of material around the outside of said catheter.
A further aspect of the invention is directed to a catheter/dilator assembly including a catheter assembly and a dilator. The catheter assembly includes a catheter having a proximal catheter end, a distal catheter end, a lumen, and an outer catheter surface. The catheter assembly also includes a material-directing element, movable between radially expanded and radially collapsed states, secured to and extending past the distal catheter end. The material-directing element has an axial length when in the radially collapsed state. The dilator includes a hollow shaft within the lumen of the catheter. The hollow shaft has an outer shaft surface, a proximal shaft end, a distal shaft end and a recessed region in the outer shaft surface at the distal shaft end. The recessed region and the material-directing element are generally aligned with one another. A compression element covers the material-directing element to temporarily retain the material-directing element in a radially collapsed state. The recessed region is sized for receipt of at least substantially the entire axial length of the material-directing element so to reduce the radial cross-sectional dimension of the assembly at the material-directing element.
BRIEF DESCRIPTIONIn brief one embodiment of this invention is particularly adapted to the removal of blockages in hemodialysis grafts. That embodiment combines a catheter having a blocking feature that blocks the annulus between the catheter and the graft and a support wire having an occlusion engaging element.
The support wire extends through the catheter, through or around the occlusion and at its distal end has an annular braided element attached thereto. The support wire is a dual element support wire having a core and an annular shell that slides on the core. The distal end of the core is attached to the distal end of the annular braided element and the distal end of the shell is attached to the proximal end of the annular braided element. Thus movement of the core and shell relative to one another moves the braided element from a radially retracted position which is useful for insertion through the catheter to a radially expanded position which expands it to the sidewall of the graft. When the annular braided element is in its radially compressed state, it can be passed through the occlusion together with the rest of the wire to reside on the distal end of the occlusion. When the braided element is expanded and moved proximally (that is, in a retrograde fashion), it will engage the occlusion and force the occlusion into the catheter. Alternatively, no motion of the engaging element may be required if aspiration is applied. In this case, the engaging element acts as a seal to prevent the suction from aspiration to remove much material beyond its point of deployment in the channel.
The distal end of the catheter is proximal of the occlusion and contains a blocking mechanism that extends radially from the distal end of the catheter to the wall of the graft or body passageway. This catheter blocking element also has a radially retracted insertion state and a radially expanded blocking state. The blocking element is a multi-wing malecot type device which is covered by a thin elastomeric film or membrane.
This malecot type of device is bonded to the distal end of the catheter or an integral part of the catheter. The distal tip of the dilator, over which the catheter is inserted, has a slightly increased diameter. This tip is in the nature of a ferrule. When the dilator is removed, the ferrule abuts against the distal end of the multi-wing malecot pushing this blocking element from its radially compressed state into its radially expanded state. Alternatively, the tip of the dilator can be bonded to the catheter with a break-away bond so that when the dilator is removed, the blocking element is expanded in a similar fashion. In this radially expanded state, the malecot and its film cover blocks the annulus around the catheter so that the occluded blood or other obstruction which is being removed is forced into the catheter where it is aspirated or otherwise removed.
Conversely, it is understood that the blocking element could be fabricated from tubular braid and the engaging element could be formed from the malecot style configuration.
Another embodiment of this invention is particularly adapted to the anchoring of wires or tubes within the tubular channels of the body including, but not limited to veins, arteries, intestines, nasal passages, ear canal, etc. Further, this anchoring embodiment has a applicability in applying an anchor to tissues or other matter to areas of the body other than in tubular channels including, but not limited to the face, breast joints, etc. This embodiment has a support wire with an engaging element.
The support wire is a dual element support wire having a core and an annular shell that slides on the core. The distal end of the core is attached to the distal end of the annular braided element and the distal end of the shell is attached to the proximal end of the annular braided element. Thus movement of the core and shell relative to one another moves the braided element from a radially retracted position which is useful for insertion into the body to a radially expanded position which expands it to the sidewall of the tubular channel or against other tissue or matter within the body. When the annular braided element is in its radially compressed (smaller diameter) state, it can be passed through or around occlusions together with the rest of the wire to reside on the distal end of the occlusion in the case of tubular channels with occlusions. It is a preferred embodiment of the instant invention that it can be made very small. When the braided element is expanded and pulled proximally (that is, in a retrograde fashion), it will engage the walls of the tubular channel and the elongate support wire can be put into tension. This distal engaging tubular braid element may or may not be covered by or integrated with a thin film or membrane to create patency or other desirable characteristics.
The instant invention also describes another use of the same device of the instant invention with minor changes. In this case, the tubular braid distal expansile mechanism may be used on the end of a guide wire or catheter so that once deployed in a tubular channel with flow such as arteries and veins, the expanded mechanism can carry the support wire in the direction of the flow. In order to accomplish this flow characteristic of the instant invention, it may be desirable to deploy the distal expanding tubular braid whereby the support wire becomes ‘floppy’ in nature so that it will flow with the expanded ‘umbrella’. The author uses the phrase ‘umbrella’ only as a communication tool in that an umbrella starts out with a small diameter shaft in its un-deployed condition (radially compressed condition) and ends up with a large diameter configuration when deployed. The shape of the expanding mechanism is varied and includes, but is not limited to an umbrella shape, a spheroid shape, an ovoid shape, a conical shape, a disc-shape, etc. The inventors have fabricated at least all of the aforementioned shapes using tubular/annular braid and successfully tested the flow, anchoring, tensioning and occlusion characteristics in both a static and dynamic in vitro environment. Creating the expanded annular braided mechanism is accomplished by pulling the inner wire of the support wire out of the outer tube. The outer tube can be made of very flexible material so that the inner wire gives the structure all of the support. When the ‘umbrella reaches the desired location which is usually determined by image intensification including, but not limited to x-ray, ultrasound, MRI, etc., the inner wire can be re-inserted into the flexible outer tube of the support wire to give the desired support required. Also once the ‘umbrella’ with the flexible outer tube needs to be removed, the inner wire can be an actuator to un-deploy the expanded braided element back to its smaller and radially compressed size. This is accomplished by bonding the outer tube of the support wire to the distal end of the tubular braid expanding element and the inner wire of the support wire is slightly bonded to the distal end of the braided expanding element. This slight bond could also be an interference fit where the inner wire snaps into and out of the distal end of the braided expanding element.
Even further, by making another minor change to the instant invention would be to use the braided expanding element as a permanent or temporary occluder without the support wire being left in place. This is accomplished by having the outer tube not bonded to the proximal end of the expanding element and the inner wire of the support wire to be only slightly bonded to the distal end of the expanding braided element. In this case, the inner wire is pulled in a retrograde direction relative to the outer tube. This action causes the expanding braided element to expand radially. Once the expanding element expands to the desired shape for the particular application and occlusion, the inner wire is pulled out of the ‘snap’ or interference fit on the distal end of the expanding braided element and the expanded braid occluder is left in place when both the inner and outer member of the support wire is removed from the body.
Hence, nearly the same invention allows the use for four different applications in the health care field.
Pertinent descriptions are set forth in a number of issued U.S. patents, including U.S. Pat. Nos. 5,275,611, 5,312,360, 4,696,304, 5,176,659, 5,437,631, 5,606,979, 5,779,672, 5,456,667, 5,733,294 and 5,209,727. A pin vise for helping grip the proximal end of a guide wire is illustrated in U.S. Pat. No. 4,858,810. U.S. Pat. Nos. 5,275,611, 5,312,360 describe a tension guide and dilator. U.S. Pat. No. 5,779,672 describes a detachable inflatable occlusion balloon. U.S. Pat. No. 5,456,667 describes a temporary stent on a catheter. U.S. Pat. No. 5,733,294 describes a self-expanding cardiovascular occlusion device. U.S. Pat. Nos. 5,437,631, 5,591,204 and 5,383,897 describe a puncture wound sealer. U.S. Pat. No. 5,626,614 describes a tissue anchor for anchoring the stomach to the abdominal wall. U.S. Pat. No. 4,372,293 describes an instrument for the surgical correction of ptotic breasts. U.S. Pat. Nos. 5,730,733 and 5,336,205 describe flow-assisted catheters.
Various features and advantages of the invention will appear from the following description in which the preferred embodiments have been set forth in detail in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGSFIGS. 1 and 2 illustrate an expandable element guide wire in radially contracted and radially expanded states;
FIG. 3 illustrates an alternative embodiment of the expandable element guide wire ofFIG. 2;
FIG. 4 illustrates a needle inserted into a graft near an occlusion;
FIGS. 5-7 illustrate insertion of an expandable element guide wire through the needle ofFIG. 4, expanding the expandable element and then removing the needle leaving the guide wire in place;
FIG. 8 illustrates a recessed dilator;
FIG. 9 illustrates a funnel catheter assembly;
FIG. 9A is a cross sectional view takenlong line9A-9A ofFIG. 9;
FIG. 10 is an isometric view of the split stopper sleeve ofFIG. 9;
FIG. 11 shows inserting the recessed dilator ofFIG. 8 into the funnel catheter assembly ofFIG. 9 to create a funnel catheter/dilator subassembly;
FIGS. 12 and 13 show movement of the compression sleeve over the funnel element ofFIG. 11;
FIG. 14 is an enlarged side view of a tearaway sleeve;
FIG. 14A is a cross sectional view takenlong line14A-14A ofFIG. 14;
FIG. 15 illustrates sliding the tearaway sleeve ofFIG. 14 onto the subassembly ofFIG. 11 to create a catheter/dilator assembly;
FIG. 16 illustrates the result of sliding the assembly ofFIG. 15 over the expandable element guide wire ofFIG. 7;
FIG. 17 illustrates the assembly ofFIG. 16 after the tearaway sleeve has been pulled proximally to allow the funnel to expand;
FIG. 18 shows manipulating the apparatus ofFIG. 17 to drive the occlusion into the funnel;
FIG. 18A is an enlarged cross sectional view takenlong line18A-18A ofFIG. 18;
FIG. 19 is an enlarged side view of the proximal and distal portions of a rapid exchange dilator assembly;
FIG. 20 is a partial cross sectional view of the distal end of the assembly ofFIG. 19;
FIGS. 21 and 22 are cross sectional views taken along lines21-21 and22-22 ofFIGS. 19 and 20, respectively;
FIG. 23 shows a heart having a bypass graft connecting the ascending aorta and a coronary artery;
FIGS. 24-28 illustrates the use of the rapid exchange dilator assembly ofFIG. 19 to access a position along the bypass graft ofFIG. 23;
FIGS. 29 and 30 are cross sectional views of the distal ends of two embodiments of a funnel catheter;
FIG. 31 shows the funnel catheter ofFIG. 30 in a radially expanded state;
FIG. 32 shows an alternative embodiment of the funnel catheter ofFIG. 31 with an elastic film on the outer surface;
FIGS. 33 and 34 show the placement and use of the funnel catheter ofFIG. 30 within a vessel;
FIG. 35 illustrates a mandril having tapered proximal and distal portions wound in a braided fashion to create a braided structure;
FIGS. 36-39 show the braided structure ofFIG. 35 used to make a funnel catheter, the braided structure being in an expanded diameter state in larger diameter and smaller diameter vessels;
FIG. 40 shows an alternative to the embodiment ofFIG. 37;
FIGS. 41 and 42 show two different embodiments to the embodiment ofFIG. 36;
FIGS. 43 and 44 show two additional embodiments of the braided structure ofFIG. 35;
FIGS. 45 and 46 show an alternative winding pattern to create windings more closely spaced at the proximal portion than at the distal portion;
FIGS. 47 and 48 are similar toFIGS. 36 and 37 but use the winding pattern ofFIG. 45;
FIG. 49 shows an alternative winding pattern to create windings more closely spaced at the distal portion than at the proximal portion;
FIGS. 50 and 51 are similar toFIGS. 47 and 48 but use the winding pattern ofFIG. 49;
FIGS. 52 and 53 show a balloon funnel catheter within a vessel near an obstruction in radially expanded and radially contracted states;
FIG. 54 is an enlarged partial cross sectional view of the balloon ofFIG. 53;
FIGS. 55-58 illustrate securing an end of a tubular braid within the end portion of a tube using a heated tool and a mandril;
FIGS. 59 and 60 illustrate two embodiments of a radially expandable and contractible braided device in which the expansion is controlled by the application of a material over portions of their lengths;
FIGS. 61 and 62 illustrate the use of a radially expandable device to impart a shape to a membrane;
FIG. 63 shows a first end of anastomotic medical device placed within a tubular structure;
FIGS. 64 and 65 show the second end of the tube of the device ofFIG. 63 with an actuator pulled proximally inFIG. 65 so to expand the tubular braided anchor member ofFIG. 63;
FIG. 66 shows the device ofFIG. 63 with the tubular braid anchor member in a radially expanded state and the dilator and guide wire removed;
FIG. 67 is similar toFIG. 66 but shows the use of hooks to help secure the tubular braid anchor member to the tubular structure;
FIGS. 68 and 69 show a tubular mesh braid in axially compressed and axially expanded states;
FIG. 70 is similar toFIG. 68 but shows the use of hooks to help secure the tubular mesh braid to a vessel wall;
FIG. 71 illustrates a tubular braided type of anastomotic medical device covering the opposed ends of a severed tubular structure;
FIG. 72 illustrates an internally applied tubular braided type of anastomotic medical device used to secure the ends of a severed tubular structure;
FIGS. 73 and 74 are similar toFIGS. 71 and 72 but include the use of hooks to help secure the anastomotic medical devices to the tubular structures;
FIGS. 75 and 76 show two different types of variable porosity anastomotic medical devices;
FIG. 77-80 illustrate malecot-type of anastomotic medical devices in radially expanded and radially contracted states;
FIGS. 81 and 82 show a variable porosity expandable device in radially contracted and radially expanded states;
FIGS. 83 and 84 show a spiral ribbon type of radially expandable and contractible device in radially contracted and radially expanded states;
FIG. 85 is an end view of a coiled cylinder type of radially expandable and radially contractible device;
FIGS. 86-91 show different embodiments of a malecot-type of anastomotic medical device in radially expanded and radially contracted states;
FIGS. 92 and 93 show a self expanding braided type of anastomotic medical device in a radially contracted state within an outer tube inFIG. 92 and in a radially expanded state after being extended from the outer tube inFIG. 93;
FIG. 94 illustrates an alternative to the tubular braid anchor member ofFIG. 63 in which one or two radially expandable mechanisms are used to engage the periphery of the opening in the tubular structure; and
FIGS. 95-97 illustrate a tubular mesh braid at the distal end of an endo device at different states within a tubular structure.
FIG. 98 is a mechanical schematic showing a device made according to this invention fully deployed in a plastic graft used in hemodialysis. TheFIG. 98 drawing shows the blocking element at the distal end of the catheter in its radially expanded state and the occlusion engaging element at the distal end of the support wire in its radially expanded state. It is important to note that the blocking element may take a variety of shapes as would be required for the particular application. The preferred shape is likely to be a funnel shape where the larger diameter is distal to the lesser diameter that is proximal on the element. This funnel shape allows the obstruction to be more easily accepted into the catheter due to the pull/push of the engaging element, aspiration or both.
FIG. 99 is a longitudinal view of the distal portion of the support wire with a braided occlusion engaging element in its radial compressed state. This is the state where the support wire and engaging element can be inserted through the occlusion that is to be removed.
FIG. 100 shows theFIG. 99 braided occlusion engaging element in its radially expanded state, which is the state shown inFIG. 98.
FIG. 101 shows the multi-wing malecot type blocking element at the distal end of the catheter in its radially expanded state, which is the state shown inFIG. 98. It should be noted that the scale of theFIG. 101 catheter is much reduced compared to the scale of the occlusion removal wire and braided element shown inFIGS. 99 and 100.
FIG. 102 is a longitudinal view, in partial cross-section, showing the catheter and dilator with a ferrule at the distal tip of the guide wire in a passageway having an occlusion that is to be removed.
FIG. 103 shows the next step in which the dilator is being removed thereby causing the malecot type blocking mechanism to become expanded by virtue of pressure against the distal end of the catheter tip of the dilator.
FIG. 104 shows the next step in which the support wire together with the braided occlusion removal element in its radially compressed state (the state shown inFIG. 99) is inserted through the catheter and through the occlusion to be removed.
FIG. 105 shows the next step in which the braided occlusion removal element has been expanded and is being pulled in a proximal direction thereby forcing the occlusion into the catheter for removal with or without aspiration.
FIG. 106 shows the multi-wing malecot type blocking element at the distal end of the catheter in its radially expanded state in accordance with another embodiment of the present invention.
FIG. 107 shows the shape of the expansion resulting from the malecot type blocking element shown inFIG. 106.
FIGS. 108A-108C illustrate the use of a tissue removal assembly made according to the invention.
FIG. 109 shows the use of a sleeve which helps prevent seeding of a tissue track and provides access to a void within the patient.
FIGS. 110A-110H illustrate a further aspect of the invention by which percutaneous removal of target tissue from a target site within the patient is accomplished using a radially expandable/collapsible tubular shaft.
FIGS. 111A-111D show a method for percutaneously removing an entire tissue mass from a target site.
FIGS. 112A-112D illustrate a target tissue removing device including a pair of tissue engaging devices which bracket the target tissue.
FIGS. 113A-113C show the use of a pair of locational elements, one of which is left in place after target tissue is removed to provide guidance for re-access to the target site.
FIG. 114A illustrates a cross-sectional view of a patient's breast following removal of tissue at a target site, and illustrating a cavity created by the removed tissue, a sheath extending to the cavity, and an expandable element insertion device passing through the sheath into the cavity.
FIG. 114B illustrates an expanded expandable element within the void ofFIG. 114A.
FIGS. 114C-114E illustrate a loop type cutter, shown in more detail inFIGS. 115A-115F, separating a layer of tissue surrounding the expanded element.
FIG. 114F illustrates the removal of the separated layer of tissue with the aid of suction.
FIG. 114G illustrates an alternative to the use of suction inFIG. 114F using a radially expandable and contractible mesh material.
FIG. 114H illustrates the resulting cavity.
FIG. 114I illustrates an enlarged, simplified cross-sectional view of the layer of tissue removed during the steps of theFIGS. 114A-114H.
FIGS. 114J and 114K illustrate alternatives to the balloon-type expandable element ofFIG. 114B.
FIGS. 115A-115F illustrate the opening and closing movements of the loop type cutter shown in FIGS.114C-114E.;
FIGS. 116A-116D illustrate the use of a radially expandable mesh type cutter to separate a layer of tissue surrounding a void having an expanded expandable element therein.
FIGS. 117A-C show the insertion of a flexible implant through a sheath providing access to a void within a patient's breast.
FIG. 118A illustrates placement of the suction inlet of a section device within a void at a target site within a patient.
FIG. 118B shows a blocking element shaft passing through the collapsed tissue at the target site, created by withdrawal of fluid through the suction device ofFIG. 118A, and a radially expanded blocking element positioned distally of the target site.
FIGS. 118C-118E illustrate the positioning of a wire tissue cutter at the collapsed tissue ofFIG. 118B, the radial expansion of the wire tissue cutter and the rotation of the wire tissue cutter to separate a layer of tissue surrounding the target site.
FIGS. 118F-118H illustrate passing a radially expandable, tubular mesh material between the separated layer of tissue and the surrounding tissue and then removal of the separated layer of tissue simultaneously with the removal of the tubular mesh material and the blocking element.
FIGS. 119A-119C illustrates an alternative to the method illustrated inFIGS. 118A-118H in which after the tissue has been collapsed using the suction device, as shown inFIG. 119B, a cutter element, such as illustrated in one or more of the above embodiments, is used to separate a layer of tissue surrounding the suction inlet of the suction device for removal from the patient.
FIG. 120 is a schematic illustration of a guide wire or catheter constructed in accordance with the principles of the present idea.FIG. 120-A is an illustration of the expandable guide wire or catheter in its relaxed un-deployed state (normally closed).FIG. 120-B is a schematic illustration of the expandable guide wire or catheter in its expanded state.FIG. 120-C is a schematic illustration of the ‘detached’ occluder.
FIG. 121 is a schematic illustration of the annular or tubular braid used in the instant invention.
FIG. 122 is a schematic illustration of the expanded braided ‘umbrella’ mechanism in place in a tubular channel of the body where the expanding element is used as an occluder, anchor, flow director or tensioner.
FIG. 123 illustrates the instant invention as it is being used as a detachable occluder.FIG. 123-A is a schematic illustration of the detached occluder in place in a tubular channel within the body.FIG. 123-B is a schematic illustration of the occluder being advanced in a tubular channel toward an aneurysm.FIG. 123-C is a schematic illustration of the detached occluder in place in the aneurysm. AlthoughFIGS. 122 & 123 indicate use of the instant invention in a tubular channel of the body, it is recognized and disclosed heretofore that the instant invention has applicability toward many other areas other than those in the figures including, but not limited to anchoring the intestines or stomach, anchoring hearing aids, occlusion of any hollow structure, anchoring the bladder, anchoring the breasts to create a lifting force, anchoring the facial tissues to lift those tissues, etc. Further, although the instant invention inFIG. 120-B illustrates a relative motion of the inner and outer elongate member, it is recognized and disclosed heretofore that the expanding mechanism may be deployed any number of ways including, but not limited to self expansion (permanent set in the expanding mechanism that is constrained by an outer tubular channel prior to deployment, magnetic means, thermal gradient mechanisms, electrical stimulation, etc.
DESCRIPTION OF PREFERRED EMBODIMENTSClot Dragger LockOne aspect of the instant invention relates to a locking mechanism for the blocking or engaging element. Of particular relevance is the locking mechanism of the engaging element. One such preferred embodiment incorporates an interference fit when and inner and outer slidable elongate member is used. Once deployed, the force required to keep the engaging element is usually small in relation to the force required to deploy (in the case of a non-self-expanding mechanism). In this case, a slight interference fit between the inner and outer slidable elongate members can be overcome easily by the interventionalist, but when the engaging or blocking element is deployed (partially or fully), the interference fit creates enough force of the system to remained deployed. The same invention could be used in the case where either the engaging element or blocking element is self-expanding, but in this case the interference fit would keep either element in the un-deployed, un-expanded condition.
This aspect is particularly useful for the engaging element because such an interference fit can be constructed particularly small. In the case of where the matter removal system of the instant invention is used percutaneously (through the skin) and a needle is used for the initial entry of the engaging element, it may be inserted through the small needle (usually 19, 18 or 21 gauge needle that is typically used for such intervention) and then deployed. In this case the needle is removed and it needs to be removed over the elongate shaft of the engaging element (wire guide). In order for it to be removed easily, the locking mechanism must be small or negligible with respect to the shaft of the elongate engaging element. A preferred embodiment of this locking mechanism in the case where the engaging element has an inner elongate member is to put a slight bend or kink in the inner member that interferes/impinges against an outer tubular elongate member. In particular, there may be three components to the outer tubular elongate member to facilitate said locking of the engaging element. The first component is the main and longest part of the shaft of the elongate member. This material can be matched to the required characteristics required for the shaft such as torqueability, steeriblity, flexural modulus, softness, stiffness, etc. This first component may be attached to the proximal side of the engaging element mechanism, but not attached to the inner tubular or wire elongate member contained within. The second component could be located proximal to the main shaft. This embodiment would be a handle type tubular element that would be sized to fit the physician's fingers, approximately 0.5-2.0 inches in length. It would not be glued or otherwise attached to the inner member. It would be manufactured of a material that might be different from the main shaft where characteristics of the first and second component could be different. The outside surface of this handle may be roughened or have some high friction coating put on it that would aid with the physician grasping the handle. This second component may require some ‘stiffness’ in it in such a case where the inner tubular or wire elongate member is kinked or otherwise bent. This second material may be harder or stiffer so that the kink on the inner member that prevents axial motion does not flex or distort the material. This second material stiffness might be such that it is important that the kink or bend in the inner member interfere enough and have enough force to hold the expanding element in place once deployed (or un-deployed in the case of the expanding mechanism being in the smaller unexpanded condition). Further, to create the appropriate interference, the inner diameter of this second component could be even smaller than the inner tubular or wire elongate member. It is possible to design an inner diameter of this second component to be 0.0001 to 0.002 inches smaller in diameter than the inner elongate member. This interference fit would be sufficient to hold the expanding mechanism expanded or unexpanded yet the interference force would not be too great that the physician could not overcome the force easily to deploy or un-deploy the mechanisms. Further a combination of smaller or equal or slightly larger inner diameter of this second component than the diameter of the inner elongate member could be coupled with the kink/bend/ferrule or other diametrical addition such as a drop of glue or epoxy to cause a brief interference fit could be used for locking either expandable mechanism.
The third component may be approximately the same outside diameter of the first and second component, but would like be glued or otherwise attached to the inner tubular member by glue or other adhesive, heat staking (or melting the polymeric handle to the inner member) or a ‘pressed’ interference fit so that this third component would move in tandem with the inner elongate member.
Hence in such a configuration, the physician would use his/her two hands (two fingers on each hand) to deploy and un-deploy and lock and unlock the expanding and contracting mechanisms respectively. This is accomplished by the physician grasping the third component with one hand and the second component with the second hand and pulling the two components apart so that a space would be created between the two components nearly equal to the distance that is changed from the deploying/undeploying distal element.
To aid with ease of use, the two handles may be color coded so that the physician would realize the difference between the two handles and for education in training them to use the locking mechanism.
FIGS. 1 and 2 illustrate an expandableelement guide wire10 comprising outer andinner guide wires12,14. A braidedexpandable element16 has aproximal end18 secured to thedistal end20 ofouter guide wire12 and adistal end22 secured to thedistal end24 ofinner guide wire14. Theproximal end24 ofinner guide wire14 has adeployment grip26 secured thereto. Theproximal end28 ofouter guide wire12 is spaced apart fromdeployment grip26 to create a lockingregion30. Relative movement between the outer andinner guide wires12,14 can be restricted by aguide wire lock31.Guide wire lock31 includes akink32 ininner guide wire14 alongregion30 and akink engagement sleeve34 slidably mounted onregion30 ofinner guide wire14.Kink engagement sleeve34 may be secured toouter guide wire12 or not. A suggested inFIG. 2, pulling on inner guidewire deployment grip26 to separate proximal ends24,28, while maintainingkink engagement sleeve34 adjacent toproximal end28 ofouter guide wire12, causes kink32 to move within the deformablekink engagement sleeve34. The resistance to kink32 moving withinkink engagement sleeve34 maintainsexpandable element16 at the radially contracted condition ofFIG. 1 or at any of a range of radially expanded conditions, such as that shown inFIG. 2.Expandable element16 may be another type of expandable element, such as a malecot type of expandable element (that is a tube having a number of longitudinally extending slits) or a wire basket/expandable braidexpandable element16A as shown inFIG. 3. Also, kink32 could be replaced by other types of a engagement sleeve-deforming structure, such as a ball or ring of material positioned along lockingregion30.
Catheter/Dilator Assembly and MethodAnother aspect of this invention is particularly adapted to the removal of blockages or particulate (matter) in hollow tissues. This aspect combines a catheter having a blocking feature that block the annulus between the catheter and the vessel or other hollow tissue. Said catheter may have an inner support wire having an occlusion-engaging element also.
Said support wire extends through the catheter, through or around the occlusion, and at its distal end has an annular braided element attached thereto or a malecot style element with two or more slits in a tube. The support wire is a dual element support wire having a core and an annular shell that slides on the core. The distal end of the core is attached to the distal end of the annular braided element (or slit-tube/malecot) and the distal end of the shell is attached to the proximal end of the annular braided element (or slit-tube/malecot). Thus movement of the core and shell relative to one another moves the braided element from a radially retracted position, which is useful for insertion through the catheter to a radially expanded position, which expands it to the sidewall of the graft. When the annular engaging element is in its radially compressed state, it can be passed through or around the occlusion together with the rest of the wire to reside on the distal end of the occlusion. When the engaging element is expanded and moved proximally (that is, in a retrograde fashion), it will engage the occlusion and force the occlusion into the catheter. Alternatively, no motion of the engaging element may be required if aspiration is applied. Further, aspiration and proximal motion of the engaging element may be used together in a synergistic fashion to remove the occlusion.
The distal end of the catheter is proximal of the occlusion and contains a blocking mechanism that extends radially from the distal end of the catheter to the wall of the graft or body passageway. This catheter-blocking element also has a radially retracted insertion state and a radially expanded blocking state. The blocking element is a multi-wing malecot type device, which may be covered by a thin elastomeric film or membrane. An alternative design of the blocking element is a mechanism of tubular mesh braid, which may be covered as well.
This malecot (or the mechanism of tubular mesh braid) is bonded to the distal end of the catheter or an integral part of the catheter. The blocking element (or the engaging element for that matter) is deployed in several different ways: 1.) The distal tip of the dilator, over which the catheter is inserted, has a slightly increased diameter. This tip is in the nature of a ferrule. When the dilator is removed or pulled in a retrograde (out of the body), the ferrule abuts against the distal end of the multi-wing malecot (or tubular mesh braid) pushing this blocking element from its radially compressed state into its radially expanded state. 2.) Alternatively, the tip of the dilator can be bonded to the catheter with a breakaway bond so that when the dilator is removed, the blocking element is expanded in a similar fashion. In this radially expanded state, the malecot (or tubular mesh braid) and its film cover (if required) blocks the annulus around the catheter so that the occluded blood, emboli, plaque or other obstruction which is being removed is forced into the catheter where it is aspirated, obliterated or otherwise removed. 3.) Further, both the blocking element or the engaging element could be formed of such materials that have a memory and hence are self-expanding. These materials are varied from polymers to metals including, but certainly not limited to: PEBAX, nylons, ployurethanes, polyethylenes (HDPE, UHWPE, LDPE, or any blend of the aforementioned polyethylenes), PET, NiTi, MYLAR, Nickel Titanium Alloy; with or without TWSM (Two Way Shape Memory or superelastic properties). In the case of self-expanding blocking or engaging elements, the larger, expanded configuration could be constrained by an outer tube to keep it in a smaller unexpanded configuration; alternatively an inner support member could be used to keep the elements in the smaller unexpanded configuration. 4.) Even further, both the blocking and engaging elements can be deployed by moving two slidable elongated elements with respect to one another. This motion of the two slidable elements would cause the blocking or engaging element to become expanded and/or unexpanded.
Dilator RecessAnother aspect of the instant invention is related to the expanding mechanism on the blocking or engaging element, but likely more pertinent to that of the blocking element on the catheter or tubular device. This aspect is related to decreasing the space required for placement of the blocking element in the un-deployed, unexpanded condition. In the case where a percutaneous entry is made into a hollow organ, the most common approach to entry is a technique known as ‘dilation’ or more specifically the ‘Seldinger Approach’ to dilatation (after a Dr. Seldinger in the mid 1900's). This is where the interventionalist uses a needle to enter the body, then a guidewire is placed through the needle and the needle is removed as stated above. Then an assembly known as a dilator/sheath assembly is inserted over the guide wire and into the body. The dilator/sheath assembly is made up of an inner dilator with a hole though the middle of the usually somewhat solid cylindrical dilatory for inserting the guidewire there through. The dilator is tapered like a cone usually on a small degree taper approximately 4-20 degrees. The sheath consists of a thin walled tube usually made from PTFE, FEP, polyurethane, PEBAX or similar material and fits snugly over the inner dilator. Conventionally, once the physician dilates into the body, the inner dilator is removed so that the physician has access to the body thorough the thin walled dilatory (0.004-0.018 inches thick). How this relates to the instant invention is interesting in that the inner dilator usually tends to be somewhat ‘solid’ in it's cylindrical configuration, but it can have a recess or groove in the cylindrical portion of the dilator for a certain portion of the dilator usually located near the distal end of the device. This recess or groove is a convenient place for the expanding blocking (or engaging for that matter) element to rest in while the device is being placed within the body. This placement of the blocking or engaging element for that matter allows more material to be placed in the device without increasing the overall diameter of the device which is particularly important so that the physician does not have to make an access site/puncture/hole into the body larger than what is absolutely necessary. This dilator may have a lumen with a side port to enable the monorail configuration described below under Rapid Exchange. A long dilator configuration can be used to support devices traversing vessels spanning the length of the human body. By incorporating the monorail feature, the dilator can be removed from a device and guidewire that is only slightly longer than the dilator shaft.
FIGS. 4-18A illustrate novel method and apparatus in conjunction with an exemplary thromboectomy procedure.FIG. 4 illustrates aneedle36 inserted into agraft38, or other tubular structures such as a blood vessel, having anocclusion40 within alumen42. An expandableelement guide wire10 is shown inFIG. 5 passing intolumen42 with the aid ofneedle36 withexpandable element16, in a radially contracted state, positioned distally ofocclusion40.FIG. 6 illustratesexpandable element16 placed in a radially expanded state by pulling ondeployment grip26.FIG. 7 illustrates removal ofneedle36 while leavingguide wire10 in place.
FIG. 8 illustrates a recesseddilator46 to be used with thefunnel catheter assembly48 ofFIG. 9.Dilator46 includes ahollow shaft50 having a fitting52 at aproximal shaft end54 and arecess56 at adistal shaft end58.Shaft50 terminates at atip59.
FIGS. 9,9A and10 illustratefunnel catheter assembly48 to include acatheter60 extending from aproximal catheter end62 to adistal catheter end64. A radiallycollapsible funnel element66 extends fromdistal catheter end64.Funnel element66 is preferably a braided funnel element having a normally radially expanded state, shown in solid lines inFIG. 9, and a radially collapsed state, shown in dashed lines inFIG. 9.Funnel element66 has anaxial length68 in its radially collapsed state.Funnel catheter assembly48 also includes acompression sleeve70 and asplit stopper sleeve72, both slidably mounted oncatheter60.Split stopper sleeve72 is also illustrate inFIG. 10 and has a cutawayproximal sleeve portion74 and a weakenedregion76, the purpose for which will be discussed below.Catheter60 has alumen78, seeFIG. 9A, for receipt ofhollow shaft50.Proximal catheter end62 has aport80 connected to atube82 with a fitting84 at the end of the tube. This permits fluid or other flowable material to be directed throughlumen78.
FIG. 11 illustrates auser inserting tip60 ofshaft50 of recesseddilator46 intoproximal catheter end62 offunnel catheter assembly48. Atube clamp86 is shown mounted alongtube82.FIG. 12 illustrates recesseddilator46 fully inserted intofunnel catheter assembly48 to create a funnel catheter/dilator subassembly88.Funnel element66 is shown aligned with andoverlying recess56 with the user preparing to slidecompression sleeve70 in the direction of arrow90.FIG. 13shows compression sleeve70 fully coveringfunnel element66 and leaving a portion ofcatheter60 between the compression sleeve and splitstopper sleeve72 exposed. The provision ofrecess56 and the alignment offunnel66 withrecess56 help to minimize the outside diameter ofsubassembly88, thus helping to minimize patient trauma.
FIG. 14 illustrates atearaway sleeve92 used withsubassembly88 to create the catheter/dilator assembly94 ofFIG. 15.Sleeve92 has a smaller diameterdistal portion95 and a larger diameterproximal portion96. Theinside diameter98 ofdistal portion95 is sized to fit snugly overdistal shaft end58 ofshaft50 and funnel66 withinrecess56. Insidediameter100 ofproximal portion96 is sized to fit snugly overcatheter60. Therefore, sliding sleeve and a proximal direction, that is in the direction ofarrow102 as shown inFIG. 15, causesproximal portion end96 to contactcompression sleeve70 and initially drivecompression sleeve70, and then bothcompression sleeve70 and splitstopper sleeve72, in a proximal direction until thejunction104, seeFIG. 14A, between distal andproximal portions95,96 ofsleeve92 generally abutsdistal catheter end64 ofcatheter60. The proximal movement ofsplit stopper sleeve72 is accommodated byproximal sleeve portion74 deforming and/or deflecting as illustrated inFIG. 15. The outside diameter ofdistal portion95 is about equal to theinside diameter100 ofproximal portion96.
FIG. 16 illustrates catheter/dilator assembly94 mounted over expandableelement guide wire10, seeFIG. 7, withtip59 positioned proximally ofocclusion40. It is preferred that thejunction104 remains outside ofgraft38 to minimize the size of the access opening in the graft through which tip59 passes. To permitfunnel element66 to expand,tearaway sleeve92 is pulled proximally as indicated byarrows106; becauseinside diameter98 is smaller than the outside diameter ofcatheter60, this movement is accommodated by a weakenedregion108, seeFIG. 14, ofdistal portion95 ofsleeve92 splitting open. It is preferred that thetip110 ofdistal portion95 not split open so to accommodate any future manipulation of the assembly. This movement also causes splitstopper sleeve72 to tear along weakenedregion76 thus permittingsleeve72 to be completely removed from the apparatus. To removeocclusion40, the user may pull onguide wire10 causingexpandable element38 to driveocclusion40 towardsfunnel66; a suction force may be created intube82, typically using a vacuum syringe attached to fitting84, and thus in avacuum space112 created betweendistal catheter end64 andshaft50 as shown inFIG. 18A. Depending upon the composition ofocclusion40, the occlusion may be drawn completely intotube82.Tube82 may be sufficiently transparent or translucent to allow the presence of the remains ofocclusion40 to the visually observed by the user within the tube.
Rapid ExchangeAnother aspect of the invention relates to designs that provide for the manufacture and function of the matter removal system. One such aspect has been often referred to as a ‘Rapid Exchange’ or ‘Mono Rail’ feature. This common feature is usually used for elongated catheters when used in conjunction with guide wires (AKA wire guides). Usually an interventionalist inserts a guidewire into the body via an existing opening or through a percutaneous opening often created by a needle. The guidewire, because it is a small wire, is easier to manipulate into position than would be a catheter or other elongated device. Once in place the interventionalist usually inserts the elongated catheter or other device over the guidewire to the appropriate position hence the reason for the name guide wire. Before the development of Rapid Exchange or Mono Rail techniques, the interventionalist would need to use a guide wire that was more than twice the length of the elongated catheter or device so that the device could be inserted over the wire outside of the body while the guidewire stayed in place in the appropriate position within the body. This ‘double length feature’ provided the interventionalist the safety of inserting the device over the guidewire and at the same time holding the guidewire in place so that it does not move from the desired location within the body. This technique was cumbersome because of the double length of the guidewire. The Rapid Exchange or Mono Rail technique provide for a small hole at the distal end of the catheter or device with that hole/lumen exiting the catheter or device a short distance from the distal end, usually approximating 3-12 (7.6-30 cm) inches from the distal end of the device.
This aspect of the invention is a variation of the Rapid Exchange feature. A dilator is used within the tubular catheter or device of the instant invention whereby the dilator has the feature of having an hole from or near the distal end and then exiting some 3-12 inches from the distal end, but instead of sliding the catheter or device of the instant invention ‘over’ the guidewire, the guide wire is loaded in place inside the dilator which is inside the tubular elongate lumen of the instant invention. When the assembly gets near the trouble area in the body to be intervened, the interventionalist would then be able to steer the wire from within the dilator, but outside of the body. This allows the similar feature of the aforementioned Rapid Exchange or Mono Rail technique. When the interventionalist is near the area to be treated, he/she can remove the inner dilator leaving the inner guidewire in place and hence obviating the need for a double length guidewire.
FIGS. 19-22 illustrate a rapidexchange dilator assembly116 comprising acatheter118 having adistal catheter end120 and aproximal catheter end122.Catheter118 includes anouter catheter124 and aninner catheter126 slidably housed within the outer catheter.Outer catheter124 includes an outer catheter fitting130, fitting130 including aconventional sealing element132 to create a fluid seal betweenouter catheter124 and aproximal portion134 ofinner catheter126. While outer andinner catheters124,126 are preferably flexible along most of their lengths,proximal portion134 ofinner catheter126 and theproximal portion136 ofouter catheter124 are both preferably made of metal tubing.Inner catheter126 also includes an inner catheter fitting138 having afluid port140 opening into acatheter lumen142 ofcatheter118.
Assembly116 also includes adilator144, having adistal portion146 and aproximal portion148, and aguide wire150 extending generally parallel todilator144. In the assembled configuration ofFIGS. 19-22,guide wire150 has atip152 extending beyonddilator tip154 and a guide wireproximal end156 extending through and past inner catheter fitting138.Proximal portion148 ofdilator144 has a relatively small diameter to provide sufficient room for the passage ofguide wire150 throughcatheter lumen142 as shown inFIG. 21. However, it is desired to minimize the diameter ofcatheter118 and also haveguide wire150 pass through thedilator lumen158 atdilator tip154. Therefore, a guide wire pathway in the form of agroove160 is formed alongdilator144 to accommodateguide wire150. Towardsdilator tip154, such as about 15 cm fromtip154, anopening162 is formed indilator144coupling groove160 anddilator lumen158 to permitguide wire150 to pass alonggroove160, throughopening162, alonglumen158 and out throughdilator tip154. SeeFIG. 20. The guide wire pathway may also be created by a lumen formed indilator144 or by a separate tubular element mounted to the dilator.
Catheter118 also includes anexpandable braid164 connected to the distal ends of outer andinner catheters124,126. Pulling inner catheter fitting138 relative to outer catheter fitting130 causes braid164 to expand. Whilebraid164 may expand in a manner similar to that shown inFIGS. 1 and 2, it may also expand to create a funnel-type material-directing element as shown inFIGS. 9 and 12, discussed above, or inFIGS. 29-54, discussed below. Inner catheter fitting138 also includes a dilator/guidewire seal element166 permitting a seal to be created betweenproximal portion134 ofinner catheter126 andproximal portion148 ofdilator144.
FIG. 23-28 will be used to describe an exemplary use of rapidexchange dilator assembly116.FIG. 23 illustrates aheart170 including abypass graft172 connecting the ascendingaorta174 with acoronary artery176.FIG. 24 illustrates the passage of thefirst guide wire178 through ascendingaorta174 and intobypass graft172 with thetip180 offirst guide wire178 positions near, in this example, alesion182.Guide wire178 is typically a large, such as 0.038 in. diameter, guide wire commonly used to help the physician to get to the general vicinity of the treatment site. Thereafter, as shown inFIG. 25, aconventional guide catheter184, typically 7 French or 8 French in size, is positioned usingfirst guide wire178. Next,first guide wire178 is removed leavingguide catheter184 in position. This permits the distal portion of rapidexchange dilator assembly116 to be passed throughguide catheter184 untilexpandable braid184 extends past thedistal end186 ofguide catheter184 as shown inFIG. 26.Guide wire150 is then extended to a chosen position relative tolesion182 as shown inFIG. 27.
Dilator144 is then removed by pulling on dilatorproximal portion148 while holding inner catheter fitting138 andproximal end156 ofguide wire150. Doing so leavescatheter118 andguide wire156 in place. This is possible because of the rapid exchange nature ofassembly116 provided by the passage ofguide wire150 externally of most of the length ofdilator144. Theexpandable braid164 may then be extended to a use, material-directing state, such as the funnel shape shown inFIG. 28, to occlude blood flow to stop emboli from flowing downstream. Appropriate medical procedures, such as installing a stent or conducting angioplasty may then the accomplished.
RF BondingA further aspect of the invention relates to devices and methods for manufacturing thermoplastic materials. As the name thermoplastic implies, temperature can be used to shape, make, bend, mold, join, tip, bond, shape polymers (or metal to polymers) for use in production of components or other products. There is a plethora of techniques well known to those ordinarily skilled in the art of ‘plastics manipulation’ using heat to change the physical shape or properties of the plastic material. Injection, plug, insert, blow molding as well as heating tubes, hot water or other liquids, flame, heat guns, heat shrink tubing and other technologies too numerous to mention.
This aspect of the invention utilizes a constant temperature alloy that can be near instantly brought to a particular curie temperature. The present invention employs a temperature self regulating heater, with regulation of temperature being accomplished by employing a high density material such as a ferromagnetic, ferromagnetic or the like material having a Curie temperature at the desired maximum temperature of operation. The Curie point also known, as Curie temperature is the point/temperature at which a ferromagnetic material exhibits paramagnetism. Once this point is achieved, no additional energy is required to be put into the system and the temperature (Curie temperature) is maintained. This pre-chosen temperature can be set at a variety of temperatures depending on the chemical makeup of the ferromagnetic material and this choice can match the melt or near melt temperature of a particular plastic.
To be able to control a heating element for manufacturing/production of thermoplastic materials that does not require a temperature feedback loop to control the temperature of the particular element/die or other mechanism is desirable for several reasons. This aspect of the invention uses a ferromagnetic metal with low electrical conductivity that can be excited by a high frequency alternating current. By selecting dimensions and material parameters for the heating element, temperature regulation in a narrow range around the Curie temperature of the ferromagnetic material can be produced, despite thermal load (i.e. the melting or near melting of plastic).
This therefore does not require a conventional feedback loop (and required controllers and no necessary calibration) to control the temperature of the heating element. Specific ferromagnetic materials can be chosen that reach particular Curie temperatures, so that choosing a particular ferromagnetic material for the heating element with a particular Curie temperature for a particular application can choose a temperature. This allows a narrow range of temperatures to be achieved. Because the mechanism of use for the excitation of the ferromagnetic element is instantaneous with the alternating current source, the ferromagnetic material/element comes to its pre-destined Curie temperature very quickly. This instantaneous heat source is vital in forming thermoplastics quickly for efficient manufacturing conditions and a low cost manufacturing environment.
In brief, one embodiment of the present invention is particularly adapted to the manipulating thermoplastic materials with a die/element, mold (“heater”) for manufacturing of components or other products in the manufacturing environment. By purchasing an ‘off the shelf’ RF generator/alternating current power source, one can excite a ferromagnetic heater to its Curie temperature and then by choosing a particular ferromagnetic alloy, different temperatures can be used for the heater in the manufacture/processing of particular thermoplastic materials.
Examples of ferromagnetic materials that exhibit different Curie temperatures when excited by an alternating radio frequency source is a metal alloy composed of approximately 36% nickel and the balance iron. Often referred to as Invar orAlloy 36 due to the nickel content. Whenalloy 36 is excited to it's Curie temperature, that temperature is controlled to a near temperature of ˜230 degrees Fahrenheit. (˜230° F. or 110° C.). Choosing alloy 42 (meaning ˜42% nickel and the remaining iron), the Curie temperature achieved is ˜380° F. or 193° C. For alloy 49, a temperature of ˜475° F. or 246° C. Foralloy 32, approximately 130° F. or 54° C. Foralloy 34, 165° F. or 74° C. and for alloy 42-6, 290° F. or 143° C. So one can see that by choosing a particular ferromagnetic alloy, one can choose a particular melt or near melt temperature of a particular thermoplastic. Such ferromagnetic materials can be readily purchased from a wide variety of vendors including SCIENTIFIC ALLOYS in Westerly, R.I. ((401) 596-4947).
By connecting the power supply to the alloy though a trial and error approach the alloy became excited to its particular Curie temperature and was measured. These temperatures were delineated above. By machining different configurations in the heater element, the inventor was able to join thermoplastic materials with a variety of other materials (metals, thermoplastics, Thermoset polymers, fabrics and the like). Further, the inventor was able to form or program the thermoplastic material into what appears to be an endless variety of shapes and conditions for use.
Another aspect of the invention pertains to the engaging or blocking element. In the case where either element is somehow bonded to a tubular elongate member, this bond should be strong, but minimal in its overall size. In the case of using tubular mesh braid to attach the mechanism to the tube, often times an additional collar can be used to overlap both the tubular elongate member and the tubular mesh braid. However this aspect of the invention allows this ‘joint’ to be accomplished by joining the two components together without the addition of this collar, which is preferred because in such interventions any additional space required for ‘joints’ is a detriment to the overall functionality of the device. If collars or other assembly mechanisms are used either on the outside of the two materials or on the inside of the materials, either a larger hole/puncture into the body is required, which has an increased mortality/morbidity associated with it, or the internal diameter of the tubular elongate member is decreased, and hence the annular space is decreased and compromised because the interventionalist has less space to deliver other instruments or less space to remove matter from the body. Hence this aspect of the invention relates to the ability to ‘connect’ the tubular mesh braid to the tubular section of the catheter or device and at the same time minimizing any increased wall thickness due to collars or other assembly components. This can be accomplished in several ways.
Inmost cases the wall of the tubular elongate member is in the range of 0.002-0.015 inches (0.051-0.38 mm) thick, but more usually in the 0.004-0.006 (0.10-0.15 mm) inches thick range. Because of the way it is manufactured (with a Maypole type braider described below), the yarns used to manufacture the tubular mesh braid are usually fabricated from filaments in the range of 0.0001 to 0.005 inches (0.0025-0.13 mm) in diameter, but more usually in the 0.0015-0.003 inch (0.038-0.076 mm) diameter range. Because these individual yarns overlap, the wall thickness of the tubular mesh braid is usually double the thickness of the yarns used in its manufacture. The instant invention relates to the fact that the tubular mesh braid can be melted into the wall of the tubular elongate member with the use of heat. This is especially applicable when thermoplastic polymers are used with either one or both of the tubular mesh braid or the tubular elongate member. Using a die that conforms to the outside diameter of the tubular elongate member, both materials can be forced into the die when heat is applied and at the same time an inner mandril is placed inside the assembly that equals the internal diameter of the tubular elongate member. Using then the heat and force, the two components (the tubular mesh braid and the tubular elongate member) can meld into one unit thus minimizing the wall thickness of the two components thusly joined together. This heated die is usually accomplished using a glass or metal die. Heat is applied to the die in any of a number of ways know those normally skilled in the art including, but not limited to convection heating, electrical resistance heating, RF excitement of the metal to create heat, by merely blowing hot air over the die, etc.
A preferred embodiment of the instant invention utilizes an RF heater made from an RF power supply and a nickel iron alloy. By coordinating the radio-frequency (RF) energy with an appropriate nickel-iron alloy die, the metal alloy die can be excited by the radio-frequency energy, said excitement generating heat to the curie temperature of the alloy. The blend of nickel-iron alloy can be adjusted to reach different curie temperatures. This RF excitement is extremely fast which is critical to the efficacious manufacture of the devices. The dies can be made very small, that is with a very small amount of alloy, so that they not only heat up immediately, but they can be cooled quickly as well. Hence the less alloy in the die the faster the throughput in the manufacturing process. This technique is extremely repeatable as well due to the repeatability of the RF and the alloy interaction. These different temperatures are important as different temperatures are required for different heat bonding procedures (that are dependent both on the geometrical configuration of the heat bond as well as the materials used in the heat bond). Using this configuration, expanding mechanisms described above have been manufactured where in a preferred embodiment of the instant invention, NiTi (Nickel Titanium) tubular mesh braid with 0.003″ (0.076 mm) individual yarns have been melded into the wall of PEBAX and polyurethane sheath tubes that have a wall thickness of 0.005-0.006″ (0.13-0.15 mm) without compromising the internal or external diameters. (Have also melded 0.002″ (0.051 mm) diameter yarns into both polyethylene and FEP). Because no extra material is used for this bond and no additional area is required to make this bond this is extremely important so as to allow more matter to be removed through the internal diameter (being optimized and not decreased or compromised) and the initial puncture into the body is minimal due to the minimized/optimized external diameter of the assembly as is further described below and herewith.
Braid Shapes with Heat Treating and Elastomer (Variable Vessel Diameter)
Another aspect of the invention pertains to a funnel manufactured using tubular mesh braid. In a preferred embodiment the funnel is made of the aforementioned tubular mesh braid. In particular, the yarns in the braid are made of metal and even more particularly, of Nickel Titanium alloy (NiTi). The preferred embodiment of this aspect of the invention is such that the tubular mesh braid is attached to an inner elongate member on the distal end and an outer elongate tubular member where the braid is attached at the proximal end. As the inner member is pulled in a retrograde/proximal direction, the braid is pulled inward so that it buckles, and folds inside itself like ‘rolling a sock’. In this preferred embodiment, the braid takes on a funnel shape. In some cases the braid is covered with an inelastic or elastic membrane. This membrane can be applied by dipping, casting or spraying the braid with a dispersion including, but not limited to silicone or polyurethane. Alternatively, the membrane could be in the form of a tubular extrusion, which is then bonded with heat, or adhesive on the two (proximal and distal) ends of the braid where it is attached to the inner and outer elongate member. In the case of using the extrusion, this material includes, but is not limited to silicone, polyurethane, Chronoprene, polyethylene, C-Flex, etc
Of particular importance to the design of the tubular mesh braid is the way in which the tubular mesh braid is formed. The preferred embodiment of the instant invention forms the tubular mesh braid on a maypole braider described below using 48 carriers of yarns made from NiTi on a 48 carrier or 96 carrier maypole braider, although in some instances it may be beneficial to use machines with more or fewer yarn carriers to adjust braid performance The NiTi yarns used are small in diameter, in the range of 0.001-0.005 inches (0.025-0.13 mm) in diameter, but more specifically 0.0015-0.0025 inches (0.038-0.064 mm) in diameter. They can be formed on a cylindrical mandril on the braider usually 5-6 mm in diameter or more preferred would be a conically shaped mandril to create a mesh braid with varying wire density and varying maximum expanded diameter to facilitate funnel deployment in lumens of various sizes. In fact, the mandril shape can be set to any axisymetric shape (for instance, a rotated parabolic arc) to further optimize the performance of the expanding member. In some cases, a non axisymmetric shaped mandril may be used as well, such as an elliptical cone or a pyramid. Further, the tubular mesh braid could be self-expanding where the yarns are programmed to be in the expanded funnel configuration. In this embodiment, the system could be constrained with an over sheath to keep in the smaller, contracted condition. Conversely, the inner and outer elongate members could be held in a tensile configuration with respect to one another so that the braid is in the un-expanded shape. When the tension is removed on the inner and out elongate member, the braid expands to the funnel configuration usually 1.5-7 mm in diameter, but more specifically from 2.5-5.5 mm. In addition, any combination of active or forced expansion and self-expansion may be used to optimize the design.
An additional aspect of the invention as it pertains to how the braid opens up into a funnel shape is the way that one ‘programs’ the tubular mesh braid. When the braid is pulled together so that it folds into itself to make the funnel shape, it may be important that there is a shape memory to the braid so that it folds in a particular way both to create the funnel, but also so that when it impinges on the wall of the vessel, it does so in a least traumatic fashion so as not too damage the intima of the vessel. The NiTi wires are preferably conditioned as to behave as super-elastic or pseudo-elastic material. In the case of expanding the funnel and trying to occlude blood, it is important is that the funnel has an outward radial force onto the vessel so that it in fact occludes the vessel and stops blood flow. This is important in the case of using the invention for ‘proximal occlusion’.
Proximal occlusion, as the name indicates, is where the blood vessel is occluded proximally (up-stream) to where an intervention takes place (i.e. balloon angioplasty, stenting etc.). When the flow is stopped or reduced upstream to where the intervention is taking place, this prevents loose embolic material that may be dislodged from traveling downstream during the intervention. This dislodged emboli can be very dangerous and even cause stroke or in the worse case death.
By shaping the braid by braiding/winding it on a shaped mandril such as a tapered mandril or a mandril with various shapes on it, one can affect different characteristics of the tubular mesh braid. Braiding over a mandril tool of varying diameter with constant braiding machine speed varies the pitch of the braid and number of crossings over a given length of braid. Varying these parameters along a single braided component helps dictate where the braid will first collapse to then work as a “rolling sock”. Further, heat-treating to modify the material or braid shape has positive effects as well. One may alter the material properties of the braid only in certain parts of it so that gradients of stiffness are present along the length of the braid. These changes in stiffness may be extremely rapid to incite buckling (funnel formation) at a particular location or actuation force, or may be gradual to prevent buckling and perhaps maintain radial force. This allows the braid to fold, and to form a funnel in a particular fashion as it is being deployed. Additionally, by heat-treating the braid in such a way so as to effect a geometrical change, the braid will tend to fold/roll in a desired way so that the deployed braid/funnel occludes properly with the desired amount of radial force and at the same time expands to a desired diameter and shape, as well as expanding in an a traumatic fashion. For instance, a shape step may be formed into the braid wire so that upon actuation, the distal portion of the braid extends radially out to make contact with the vessel wall creating a deployment shape that is conducive to braid buckling. The size and geometry of this step can be adjusted to a particular application. Any sort of geometrical change can be formed during the actual braiding process, or through secondary mechanical or thermal means at any time in the manufacturing process.
Another secondary operation that may be used to improve the performance of the expanding braid section is the inversion of the braid. By turning the mesh braid “inside out”, it exhibits properties different from those of a “right side out” braid section. These differences may be greatest when the braid wire material is nitinol, and it is inverted after heat treatment, but some desirable performance characteristics may be present when using other braid wire materials, such as stainless steel, or when inverting the braid without heat treatment.
As previously mentioned, the overall profile of the device is of critical importance so that the physician can use the smallest incision necessary while still having the largest size lumen available for other therapeutic devices. With this in mind, another preferred design embodiment employs a braided shaft with an integral expanding braid section at the distal end. The braided shaft can be constructed with the desired wall thickness (specifically between 0.002″ and 0.015″ (0.051-0.38 mm)) and stiffness characteristics, and the expanding braid portions can be formed by simply continuing the braid beyond the shaft's polymer components. This process eliminates any secondary bond between the expanding braid and the shaft, and simultaneously creates a device that is stronger and more durable. One of many possible manufacturing methods entails placing the polymeric inner liner of the braided shaft on a mandril, and loading the mandril and liner assembly through the maypole braider. The mandril may have a distal shaped section that can be used to form the desired expanding braid shape. Braiding is continued over the expanding braid section of the mandril, and heat-treated if necessary. The outer polymeric component, or components are then laminated over the braided shaft section.
Using different coverings over the tubular mesh braid as well can modify all of these characteristics. For example, one embodiment of the invention would be a thermoplastic extrusion that has variable wall thickness. The wall thickness of the membrane may be varied along the length of the braid to have one or more zones of increased or decreased resistance to actuation (expansion), or zones of increased durability. These variable wall thicknesses will also allow the thinnest sections of the tubular mesh braid to expand first or to a larger overall diameter in contrast with zones having thicker membrane thicknesses. The adjustment of the order or degree of actuation of various sections along the length of the expanding braid will allow the device to achieve an optimum balance of actuation reliability, actuation force, and radial force exerted on the vessel wall. Generally, an extruder can extrude to approximately 0.003″ (0.076 mm) wall thickness of the tubing. In the manufacturing process, the technician can ‘pre-dilate’ the extrusion (all or part) and in doing so can controllably change and vary the expansion properties and wall thickness to achieve better device performance as compared to pre-dilated membranes. The easiest way to accomplish this ‘pre-dilation’ is to apply air pressure to the extrusion when it is sealed off at one end. Most thermoplastic elastomers used for this application have elastic modulus characteristics from 300-1500%, but more particularly from 600-1000%. Examples such as Chronoprene, polyurethane, C-Flex, latex, polyisoprene and silicone exhibit these properties.
FIG. 29 illustrates the distal end of afunnel catheter190 including anouter tube192 having adistal tip194, aninner tube196 having adistal tip198 and atubular sleeve200 having first and second ends202,204 secured todistal tips194,196.Tubular sleeve200 is shown in its radially contracted, deployment state. It is important thattubular sleeve200 have a generally U-shaped, direction-reversingregion206 so that when first and second ends202,204 move toward one another from their positions ofFIG. 29,sleeve200 moves to a distally opening, radially expanded, use state, such as shown inFIG. 31.FIG. 30 illustrates an alternative embodiment offunnel catheter190 in whichregion206 in the deployment state has a more pronounced U-shape than the embodiment ofFIG. 29.FIG. 31 illustratesfunnel catheter190 in a radially expanded use state.Funnel catheter190 is typically used to seal the interior of a graft, blood vessel or other hollow body structure so that the material from which funnelcatheter200 is made is typically substantially impervious to fluid flow. Whiletubular sleeve200 is preferably a braided tubular sleeve impregnated with a flexible polymer material,sleeve200 maybe constructed in other ways.FIG. 32 illustrates atubular sleeve200 and which the fluid flow barrier is provided as a flexible,elastic film208 on the outside oftubular sleeve200.FIGS. 33 and 34 illustrate placement and use offunnel catheter190 within avessel210. Pullinginner tube196 relative toouter tube198 causestubular sleeve200 to create a funnel-type material-directing element with asubstantial portion212 contacting theinner wall214 ofvessel210.Funnel catheter190 can be made to provide a sufficiently high level of force toinner wall214 over a relatively large contact area to provide a good seal while minimizing risk of tissue damage.
Other methods to achieve a funnel catheter that reliably creates a distally directed open funnel end will be described below with reference toFIGS. 35-51. In general, the different techniques include adjusting the taper angles at the distal and proximal portions of the mandril, selectively applying material to one or both of the distal and proximal portions of the braided material, and changing the pic count between the distal and proximal portions. While in practice more than one of these techniques may be used to construct a working device, the different techniques will be discussed below with regard to specific embodiments incorporating a single technique.
FIG. 35 illustrates amandril218 having aproximal taper portion220 and adistal taper portion222 connected by a central, typically constant diameter,portion224.Mandril218 is wound in a braided fashion with braid winding226 to create abraided structure228.Proximal taper portion220 has a more gradual paper thandistal taper portion222, that is θ1>θ2. In the embodiment ofFIG. 35, the pic count, that is the number of crossings ofbraid windings226 per unit length, is constant along the entire length ofmandril218. A membrane, not shown, may be used withbraided structure228. The membrane maybe incorporated into, lie on top of or be located withinbraided structure228. The membrane may be chosen to halt all fluid flow therethrough or only prevent the passage of particles having a minimum size.Braided structure228 is then removed frommandril218 and mounted to outer andinner tubes230,232 to create afunnel catheter234 with a tubularbraided sleeve236. SeeFIGS. 36-39.
Theproximal end238 ofsleeve236 is secured to afirst position240 onouter tube230 and thedistal end242 ofsleeve236 is secured to asecond position244 oninner tube232. The greater taper atdistal taper portion222, θ1>θ2, helps to ensure that thedistal portion246 ofsleeve236 buckles before theproximal portion248 of the sleeve. SeeFIGS. 38 and 39. Whileinner tube232 is shown extending distally an indeterminate distance, it may be, for example, terminated at or nearsecond position244 oninner tube232.
FIG. 36 illustrates tubularbraided sleeve236 in alarger diameter vessel250. As the vessel diameter is increased, the contact length of the braid is reduced. This makes the distal/proximal competition more important (thedistal portion246 ofsleeve236 must buckle first) because friction between the device and the vessel wall does not significantly help to create the distal funnel. Withsmaller diameter vessels254, seeFIGS. 37 and 39,outer tube230 is typically held fixed whileinner tube232 is pulled proximally. Friction betweenbraided sleeve236 andvessel254 helps to hold the proximal,outer tube230 fixed while motion at thedistal end242 ofsleeve236 makes thedistal portion246 ofsleeve236 collapse. With large vessels, seeFIGS. 36 and 38, the friction is less than with smaller diameter vessels to increase the possibility that the whole tubularbraided sleeve236 can shift (slide) potentially causingproximal portion248 ofbraided sleeve236 to buckle. When the pic count is constant or generally constant as in the embodiment ofFIGS. 35-39, is very important that the difference in the taper angles provide the necessary bias to ensure thatdistal portion246 always wants to yield first (that is, before proximal portion248) and collapse into a funnel shape as illustrated inFIG. 38.
FIGS. 37 and 39 illustrate tubularbraided sleeve236, having a constant pic count, insmaller diameter vessel254. In this situation, much of thebraided sleeve236 comes in contact with the vessel wall. Providing an appropriate difference in taper angles with θ1>θ2, ensures thatdistal portion246 buckles beforeproximal portion248.
FIG. 40 illustrates an alternative embodiment of a constant pic count tubular braidedsleeve236 designed to ensure thatdistal portion246 buckles beforeproximal portion248. Braid windings226, typically made of NiTi, atdistal end242 ofsleeve236 are heat-treated to make an abrupt diameter change after braiding. This creates a weak geometry in the shape at this position so that with the application of a small compressive load,sleeve236 will buckle in the region ofdistal end242. This effect is made more effective with increased distal end taper angle θ1and a reduced radius at this position. Other methods for creating a sharp step shape set in the braid after weaving may also be used.
FIG. 41 illustrates a further alternative embodiment of a constant pic count tubular braidedsleeve236 designed to ensure thatdistal portion246 buckles beforeproximal portion248. A part ofproximal portion248 is coated with apolymer256, which is typically somewhat elastic, to limit expansion ofproximal portion248 so it cannot fully expand and buckle. The remainder ofsleeve236 is uncoated to promote buckling atdistal portion246.
FIG. 42 similar toFIG. 41 accuses a relatively stiff, relatively stretchresistant polymer coating256 atproximal portion248 and a relatively soft, relatively easily stretchedpolymer coating258 atdistal portion246.Polymer coating256 keeps the proximal braid from fully expanding and buckling. The soft distal covering provided bypolymer coating258 allows full expansion, buckling and a good hydraulic seal to enable aspiration through the center of this device. If desired, thecentral portion260 ofsleeve236 may also be covered with the same, soft, easilystretchable polymer258 for a different polymer that may be even more easily stretched thanpolymer258.
FIGS. 43 and 44 illustrate alternatives to thebraided structure228 ofFIG. 35.FIG. 43 shows a double wire braidedstructure262 having a constant pic count. The double wire can be round or ribbon coming off 1 or 2 spools. More wires such as 2, 3, 4 or 5 can be stranded together to allow low bending forces with high hoop strength. This will allow the braid to have great composite strength with the ability to shift to a low profile and be flexible in a catheter.FIG. 44 illustrates a constant pic count ribbon band braidedstructure264.Structure264 is typically made of NiTi, stainless steel, titanium, a polymer or tungsten in sizes ranging from 0.0003 to 0.005 inch thick by 0.001 to 0.030 inch wide (0.0076 to 0.13 mm thick by 0.025 to 0.76 mm wide). One example could be 0.0005 inch thick by 0.003 inch wide (0.013 mm thick by 0.076 mm wide).
FIG. 45 shows an alternative to the constant pic count embodiment ofFIG. 35.Braided structure266 has a variable pic count with a higher pic count along theproximal taper portion268 and a lesser pic count along thedistal taper portion270.Braided structure266 can be produced by gradually speeding up the “take up” reel on the braids while running the wire spools at a constant speed. This design can be tuned to makedistal taper portion270 weaker with large openings (distance between wire crossings) so it buckles into a tunnel before theproximal taper portion268. This design can accommodate relatively large radial expansion to cover a large range of vessel sizes. Removing some of the wire strands to create braidedstructure272 as shown inFIG. 46 can create a similar effect, that is forcing distal buckling before proximal buckling. The wires are braided a distance overmandril218, every other wire is cut (as an example) and then the braiding is continued with a lower pic count and fewer number of wires.
A variable piccount funnel catheter274 is shown inFIG. 47 and includes a tubularbraided sleeve276 made frombraided structure266 ofFIG. 45. Variablepic funnel catheter274 is shown partially expanded in alarger diameter vessel250.Proximal taper portion268 ofbraided structure266 can fully expand but the taper is so gradual that it behaves more coil bound.Distal braid portion270 must have a sufficiently low pic count to be sufficiently weak to yield first.Funnel catheter274 is shown inFIG. 48 within asmaller diameter vessel254. In this case it is beneficial to have a low pic count distally sodistal taper portion270 is weaker thanproximal taper portion268 and tends to buckle under compressive load. This works well as long as the proximal end cannot fully expand in the vessel diameter. High pic counts that cannot fully expand tend to lock up with lots of support (closely spaced supporting crossings).
The variable pic count braidedstructure278 ofFIG. 49 reverses the winding pattern ofbraided structure266 ofFIG. 45 to provide a higher pic count at distal taper portion280 than atproximal taper portion282. This can be tuned to allow the smallest section of distal taper portion280 to fully expand before hitting the vessel wall, or even the smallest anticipated vessel size. At full expansion, thewindings226 of variable piccount funnel catheter284, seeFIGS. 50 and 51, atdistal end242 are pushed into nearly a coil bound hoop path that can easily buckle to create the distal funnel before the proximal end buckles. After the initial buckling, the distal funnel end can grow like a rolling sock as distal and proximal ends242,230 move towards one another to enlarge the funnel opening.FIG. 48 illustratesfunnel catheter284 withinsmaller diameter vessel252. The high pic count at the distal portion ofbraided structure286 causes the distal portion to buckle first as long as it can fully expand in the vessel. The higher the pic count of a section oftubular braided structure278 on the mandril, the less that section will expand under axial compression. The section ofstructure278 having a very high pic count will remain almost fully expanded in the low profile catheter. After actuating, the very high pic count section will become hoop-like and buckle.
A Balloon that is a Funnel
Another aspect of the invention relates to a funnel shaped balloon. This is easily accomplished by shaping the balloon in such a way so that when it is expanded by gas or liquid, it expands in the shape of a funnel. This can be accomplished in several ways. In the case of making a balloon from a thermoplastic material including, but not limited to Chronoprene, polyurethane, C-Flex, Latex rubber, etc., these can be dipped, cast, sprayed or otherwise coated on a mandril that is in the shape of a funnel, or alternatively, they can be an extrusion that is then placed on a mandril that is the shape of a funnel and then by applying heat, the polymer will take the shape of the mandril. Even further, the extrusion can be placed inside a mold that is the shape of the funnel and with the addition of heat and then applying air pressure to the inside of the extrusion, the polymer will expand to the shape of the internal configuration of the mold cavity. After heat is removed from either of the above-mentioned processes and the system is allowed to cool, the result is a balloon that is in the shape of a funnel.
Alternatively the polymer could be made of an inelastic material including, but not limited to polyethylene, PET, HDPE, etc. These shapes can be accomplished in a similar manner stated above. Further because they are inelastic in nature they can be plastically deformed to create the shape of the funnel.
Aballoon funnel catheter290 is shown inFIGS. 52-54.Catheter290 includes ashaft292 having adistal end294 to which anannular balloon296 is secured.Balloon296 extends pastdistal end294.Balloon296 defines a centralopen region298 aligned with amain lumen300 ofshaft292.Shaft292 also includesinflation lumen302 opening into theinterior304 ofballoon296.Balloon296 moves between the uninflated, radially contracted state ofFIG. 52 and the inflated, radially expanded state ofFIGS. 53 and 54.Open region298 is funnel shaped whenballoon296 is in the inflated, radially expanded state.
Expanding the Elastomer with the Braid and Applying Heat
The interaction of a braid and a membrane is obviously critical and can be optimized to provide various funnel shapes and properties. Additionally, the elastomer may be free from attachment to the expanding braid over one or more sections but still bonded proximally and distally to the outer member, and inner member, respectively. This construction has the benefit of eliminating any protrusions created by bonds or braid geometries. More specifically, it is preferred to use this technique on the distal end of the expanding braid section, creating a smooth, uninterrupted funnel shape. This smooth shape may improve fluid dynamics, perhaps by eliminating eddy currents, and allow for more complete aspiration of emboli.
It is desirable to create a membrane that is firmly attached to the braid over a section, yet is free from attachment in another section. In this manner the braid can be held in the desired shape (may be final deployed shape or any other intermediate position), and the membrane is placed over the braid. This assembly can then be placed into a heated mold, or other apparatus to heat the membrane, allowing it to flow and meld with the braid wires. Insulation may be placed in the mold to prevent the heating of certain sections of the membrane, thus keeping the membrane free from the braid.
Another aspect of the invention relates to a configuration where the polymer is shaped with the use of heat in conjunction with the expanding braid. For example, a thermoplastic elastomer (including, but not limited to polyurethane, C-Flex, Chronoprene, etc.) could be applied to the tubular mesh braid (this application could be sprayed, cast dipped, or an extrusion that lies over the braid) and then the tubular mesh braid is actuated so that it expands in any desired shape (including but not limited to funnel, disc-shape, ovaloid, spherical, conical or any other desired shape). In this case, the addition of heat would be advantageous because it would allow the polymer to form into the desired shape. This could be accomplished during and/or after the tubular mesh braid is expanded. Further, since the interaction of the braid and the membrane is obviously critical it may be necessary to control this interaction by bonding the braid to the membrane along its entire length or in discrete sections. The elastomer may be free from attachment to the expanding braid over one or more sections but still bonded proximally and distally to the outer member, and inner member, respectively. This construction has the benefit of eliminating any protrusions created by bonds or braid geometries. More specifically, a preferred embodiment is to use this technique on the distal end of the expanding braid section, creating a smooth, uninterrupted funnel shape. This smooth shape may improve fluid dynamics, perhaps by eliminating eddy currents, and allow for more complete aspiration of emboli.
In some situations it may be desirable to create a membrane that is firmly attached to the braid over a section, yet is free from attachment in another section. The braid can be held in the desired shape (may be final deployed shape or any other undeployed or intermediate position), and the membrane is placed over the braid. This assembly can then be placed into a heated mold, or other apparatus to heat the membrane, allowing it to flow and meld with the braid wires. Insulation (PTFE tubing, for example) may be placed in the mold to prevent the heating of certain sections of the membrane, thus keeping the membrane free from the braid. This forming method is viable for use with any thermoplastic braid (elastic or inelastic).
Additionally in the case of inelastic polymers, the tubular mesh braid could be used to actually plastically deform the inelastic polymer. In this case it may be advantageous to use tubular mesh braid that has a greater outward radial force so that the plastic deformation may be accomplished. This increased radial force of the tubular mesh braid could be accomplished by using yarns in the braid that are larger and stronger or both. In both instances of using the tubular mesh braid as a ‘tool’ for creating the shape of the elastomers, air pressure and heat may be used to aid with the process. In the case of the aforementioned embodiment, where one is creating a balloon in the shape of a funnel, disc, ovaloid, cone, etc, this braid could be used as a tool as well.
A method for securing anend306 of atubular braid308 to asoftenable end portion310 of atube312 is illustrated inFIGS. 55-58.End portion310 is inserted into aheated tool314 and end306 oftubular braid308 is placed within theopen end portion310 as shown inFIG. 56.Heated tool314 causesend portion310 to soften sufficiently so that when amandril316 is inserted throughtubular braid308 and into the interior ofheated tool314 as shown inFIGS. 57 and 58,first end306 oftubular braid308 is driven intosoftenable end portion310 to create a tube/braid material matrix316. The resulting bond creates a strong, intimate bond with at most an insubstantial change in either the outside or inside diameter oftube312.
Heated tool314 can be heated in a variety of conventional or unconventional manners, including electrical resistance heating and RF heating. While sensors and feedback loops may be used to keepheated tool314 at a desired temperature,heated tool314 may be made of a material having a Curie temperature at the desired operational temperature to maintain the tool at the desired operational temperature.
The shape of a radially expandable and contractible tubular device can be controlled in a manner indicated inFIGS. 59 and 60.FIG. 59 illustrates a funnel shaped radially expandable and contractibletubular braid device320.Device320 has different cross-sectional dimensions at different positions, such aspositions322,323,324 along its length, when in a radially expanded condition.Device320 may be radially expandable or contractible naturally or with the aid of an external force or stimulus, such as heating or mechanical manipulation. By varying the thickness of impregnatingmaterial326, the resistance to radially expansion can be adjusted to achieve the desired shape. For example,device320 has been made withmaterial326 thickest atposition322 with a gradual decrease in thickness atpositions323 and324, and with no material pastposition324.FIG. 60 illustrates atubular braid device330 havingelastomeric material332 along aproximal portion334 and along a distal portion335 of the device to create the expanded diameter bowling pin shape fordevice330. While the application ofmaterial326,332 may result in a material having a varying thickness over at least part of its length, the application may result in a material having a constant thickness or a finite number of thicknesses. For example, a number of bands of material, having the same or different thicknesses and having the same or different axial spacings, may be applied to the braided material. Also, different materials having the same or different stretch resistant characteristics may be used. The material may be a generally elastic material or a generally inelastic material or a combination thereof. While it is generally preferred to use an impregnatingmaterial326, an appropriate radial expansion-inhibiting material may be applied on the outer surface of the braid or, if properly attached, over the inner surface of the braid.
In some cases it may be desired to impart a shape to a thermoplastic membrane which can then be used in conjunction with a radially expandable element, such as a tubular braid element or a malecot element, to help the radially expandable element achieve a desired radially expanded shape.FIGS. 61 and 62 show the use of a radiallyexpandable device336 having inner andouter tubes338,340 and atubular braid element342 at the distal ends oftubes338,340.Device336 is a tool and could be replaced by other tools, such as a malecot device, which would serve the same function. Athermoplastic membrane344 is positioned overtubular braid element342 andelement342 is radially expanded as shown inFIG. 62. A set is imparted tothermoplastic membrane344, typically by a heating and cooling cycle; the method of imparting the set will be determined in large part by the material from whichthermoplastic membrane344 is made.Membrane344 may be an elastic material or an inelastic material.Thermoplastic membrane344 may be applied totubular braid element342 by, for example, sliding a tubular membrane overelement342 or by coating tubular braid element342 (or such other tool as may be used) with a thermoplastic liquid material. In the latter case may be desired or necessary to use one or more separation layers betweentubular braid element342 andthermoplastic membrane344.
Anastomotic Medical DevicesThis aspect of the invention relates to a device/implant, which is particularly useful for bypassing, joining or re-joining pieces of tissue in the body. Further, this aspect of the invention relates to a means for bypassing or re-joining tubular structures within the body. The system is applicable for performing an anastomosis between a vascular graft and the ascending aorta in coronary artery bypass surgery, particularly in port-access CABG surgery. Alternatively it may be used to bypass any diseased vessel (vascular or other vessel/lumen in the body. A first configuration has two parts: an anchor member, forming the attachment with the target vessel wall and a coupling member forming the attachment with the bypass graft vessel. Inserting the coupling member, with the graft vessel attached, into vessel, completes the anastomosis. A second feature of the invention includes an anastomotic fitting, having an expandable flange, which the vessel is attached which contacts the exterior surface of the target vessel. A tailored amount of pressure is applied by an expandable mechanism that then grips the target vessel wall and creates a leak-proof seal between the anastomotic mechanism and the target vessel. A third feature of the invention has a flange to which the vessel attaches, by attaching hooks that are incorporated in the expandable anastomotic device to attach to the wall of the target vessel to form the anastomosis. A method for sealing or joining a graft vessel to a target vessel at an anastomosis site, the target vessel having an opening formed therein. The method includes positioning a fastener made from a deformable material radially adjacent to a free end portion of the graft vessel. The material is transformable between a smaller and then larger size, upon application of energy to the material. The method further includes inserting at least the free end portion of the device in the target vessel through the opening in the target vessel. The free end portion of the device is radially expanded to expand the device into intimate contact with an inner wall of the target vessel. The methods and devices represented above have been at least generally represented in the attached drawings for the instant inventions.
Another aspect of the invention is particularly adapted to the anastomotic repair of hollow conduits within the body. For example if a tubular conduit in the body is partially, generally, relatively or completely blocked, diseased, restricted, etc. and the preferred solution is removal of the diseased conduit and subsequent anastomotic repair or perhaps anastomotic repair via a bypass where the instant inventions could be used for joining, re-joining or bypass of the suspect part of the conduit.
In the case where diseased conduits are removed and it is preferred that the conduit be re-joined or even replaced with other autogenous or synthetic conduit (or a combination thereof), the instant embodiments would allow the physician to insert a radially expanding tubular structure within (or over) the remaining ends of the conduit in the body. It is likely that the radially expanding tubular structure would be placed into the vessel in a condition where it is not fully expanded or in a partially radially contracted condition (or at least a somewhat radially contracted condition; although this is not a condition for the instant inventions). However, in this case, the device would be placed into both ends of the vessel (with perhaps pulling the vessels toward one another) in a condition at least equal to or less than the inside diameter of the vessel, but more likely in a somewhat slightly contracted condition. Both ends of the device may have hooks or other fasteners or even other connection areas where the device may (or may not) be attached to the visceral conduits. Additionally tissue glues commonly available today are likely to be used and may in fact be incorporated into the procedures taught herein. This may be aided with mechanical, chemical or other means or no connection at all may be required. In the case where some connection mechanism is used/required, those mechanisms may include, but are not limited to hooks, sutures, staples, adhesives, mechanical interlocking, friction, compression, etc.
This instant invention may be enhanced by the use of a tubular mesh weave or braid that has been weaved of individual yarns. The use of such a braid is common both in industry as well as medical device/implants. See, for example, U.S. Pat. Nos. 6,179,860; 6,221,006; 6,635,068; 6,258,115 and 6,450,989.
One particular advantage of this tubular mesh braid discussed in the preceding paragraph is its ability to contract and expand in a tubular fashion. The description of the tubular braid element and coatings of it are included below in this disclosure. (The coating discussed in the preceding sentence as well as below may or may not be required.) Further, instead of or in addition to the ‘coating’, the braid could be accomplished with multiple (18-144 or even more or less) ‘yarns’ so that some of the yarns could be designed such that they could act as the coating, so that it is not a coating at all, but is part of the actual braided mesh itself.
This contraction/expansion phenomenon of the tubular braid element may be useful in the instant embodiment. For example, a particular length of the braid could be formed of a particular diameter. The braid could be stretched or elongated by putting it into a somewhat tensile condition. This would allow the braid diameter to contract and hence fit easily within the tubular conduit(s) of the body. Then the braid could be allowed to relax and the diameter would expand radially to a pre-determined diameter or to the inside diameter of the visceral conduit. Conversely, the braid could be fabricated a particular diameter smaller than the visceral conduit and then put into compression to expand it radially to the appropriate diameter to join or re-join the visceral conduit. This compression or tension could then be permanently controlled if so desired by keeping the braid in an expanded condition for an appropriate period of time. Certainly this could be controlled with the use of ‘memory’ of the braid as is described below in the discussion of the tubular braid element and elsewhere. Alternatively the braid could be kept in an elongated/smaller diameter or a shortened/larger diameter by mechanical attachment that keeps the braid in the preferred condition.
This tubular mesh braid could be composed of many different materials used now in the medical device industry as well as newer yet to be released or discovered materials including, but certainly not limited to polymers such as PET's, Silicones, Nylons, Polyesters, Mylar, etc. metals and metal alloys such as Stainless Steels, Elgiloys, NiTIi's (Nickel Titanium alloys, both TWSM (Two Way Shaped Memory) and Super Elastic NiTi's), etc.
Additionally, these radially expanded devices and methods could be accomplished with a ‘slit tubular’ structure commonly referred to as a Malecot structure that can be easily expanded and contracted by putting the tube in compression or extension respectively.
Even further, these radially dilating mechanisms can be accomplished by curling material like a ‘cinnamon roll’ such that in its smaller/contracted condition, the walls of the material would be contracted and touch one another (as with a cinnamon roll) and in its larger diameter state the walls may not be in contact with one another. This cinnamon roll can be accomplished by ‘rolling’ the sheet (with porosity, holes, coverings, films, membranes, drugs, compounds, etc.) of material into a tube/cylindrical like condition in a small diameter and then when in the desired location, the rolled sheet is allowed to or effected to at least partially ‘unroll’ into at least a partially tubular structure desired.
Even further yet, the instant inventions and methods can be accomplished by a system of a sheet of material that is longer than it is wide (e.g. like a ribbon). The longer dimension is then programmed to a tubular configuration by ‘wrapping’ it around a small cylindrical mandril (or other means) and treating it to keep in that small tubular configuration. Then when in the desired location, the smaller tube can be activated to become a larger tubular configuration. One such way to accomplish this is with TWSM NiTi mentioned above and disclosed as a Multi-Porous Stent in U.S. Pat. No. 6,258,115.
In all instances these mechanisms may be covered with a film of elastic or inelastic material. Further this film may be incorporated into the mechanisms as opposed to covering them. Such films, coverings or other incorporated materials may be, but are not limited to the following: silicone, nylons, polyethylenes, wovens, hybrids, PET's, woven metals, PTFE'S, Expandable PTFE's, FEP's, Teflon's, and a variety of bioabsorbable materials such as hydromers, collagens, polymers, vicryls, autogenous substances (animal, human or plant).
There may be a support wire(s) that may extend through or alongside the expandable channel devices at its distal and proximal ends (or near them). These wires may be used to help deploy or undeploy the radially expanding elements. Further, these wire(s) may be used to help keep the preferred condition when in the preferred position in the host. The support wire(s) may be one, two, three, four or more in number and may be located inside or outside the tubular structure. They may be used to put the mechanism into a tensile or compressive condition that will allow it to become a small diameter or larger diameter condition. These wires can be made permanently attachable to keep the desired configuration by attaching them permanently to keep the mechanism in the desired shape. The distal end of the core is attached to the distal end of the annular braided element (or other mechanism described herein) and the distal end of the shell is attached to the proximal end of the annular braided element. Thus movement of the core and shell relative to one another moves the braided element from a radially retracted position, which is useful for insertion into the body in a small condition to a radially expanded position, which expands it to the sidewall of the channel in the body.
A device made according to this aspect of the invention is used for intervention into the tubular channels (arteries, veins, biliary tract, urological tract, gastro-intestinal tract, stents, grafts, sinuses, nasopharynx, heart, ears, etc.) or hollow cavities (stomach, gall bladder, urinary bladder, peritoneum, etc.) of the body. Additionally the instant invention may be used in solid or semi-solid tissue including, but not limited to breast, liver, brain, pancreas, lungs etc. It is particularly convenient to use in an operating room, surgical suite, interventional suite, Emergency Room, patient's bedside, etc. environment. One preferred embodiment of this device is that the flexible shaft is inserted into the tissue, tubular channel or hollow cavity of the body usually through percutaneous access or via a surgical incision. In the case of lumens that enter and exit the body naturally, the device may enter through one of those entry or exit paths (i.e. rectal opening, mouth, ear, etc.).
Additionally, other techniques may be used for removal assistance such as the use of lytic agents, laser energy, dissolving agents, hydraulic assistance, mechanical agitation, vibration, ultrasonic energy or any other variety of assistance that will aid in the removal. Image intensification (Ultrasound, fluoroscopy, MRI, etc.) may be used as well to help with assuring the technique/removal is successful. Additionally, direct visualization using cameras or endoscopes may be used as well.
Further, materials disclosed could be of some hybrid elastic/inelastic material or compliant material. Even further, the balloon may be aided with some other mechanical substructure that aids in the outward radial force that is created by the balloon. Further when balloons are used, filaments such as thin strips of polymers such as Mylar, pet, polyethylene, etc., could be used to create a desired effect when inflating the balloon (such as shape). All of these configurations may or may not have a roughened texture on the exterior surface that will aid in the removal of the obstruction or adherence to tissue. Alternatively, all of the above mentioned configurations could have a separate or additional material applied over the expandable mechanism that is a membrane, which may or may not be roughened. The roughened surface on the expandable mechanism is easily accomplished in the manufacturing environment. One such way is to create bubbles in a liquid slurry of the polymer prior to its solid curing. Another might be the addition of dissolvable crystals to the surface of the liquid polymer prior to its cure. These dissolvable crystals could then be removed (washed off) after curing of the polymer.
Another configuration that could be used for the expandable mechanism is a mechanism(s) known as a malecot. This malecot is a common configuration used in catheters for holding them in place (in the case of feeding tubes in the intestines or stomach). It is usually a polymeric tube that has more than one, but usually two or more slits symmetrically opposed. When the distal tip of the malecot is put into compression (usually by pulling an inner wire or mandril or tube), the sides of the polymer are pushed outward to create a larger diameter on the distal tip. This larger diameter is larger than the body/shaft of the device. In the case of a malecot type configuration (as with the inflatable mechanism(s) mentioned above), the surface of the malecot could be roughened or a separate membrane (attached or not) could be put over or under the malecot so that it is roughened or strengthened. Further, a membrane that connects the ribs or wings of a malecot is easily fabricated to increase the surface area of the malecot ribs or wings alone.
Yet, another alternative design of the expandable mechanism is one that has similarities to the malecot, but uses a multi-stranded braid on the distal end. When the braid is put into compression, the braid is pulled together and it flares out to create a larger diameter on the distal end. Changing the pore size along the braid so that the holes in the braid go from none to large holes/pores easily modifies the braid. This can be accomplished by braiding the braid with metals and polymers and melting the polymers away or by simply braiding at different rates while braiding that causes different pore sizes also known in the braiding industry as pics per inch. This is easily accomplished ‘on the fly’ while braiding by using a programmable braider. The braid pics per inch change with time as the tubular mesh braid is being braided. This varying pore size may have a number of advantages to the current invention. It could aid with stopping porosity when needed and allowing porosity when you need it. For example, it is possible that ingrowth would be desired in contact with tubular body structures at certain times and that there be no porosity when trying to achieve a leak free environment (perhaps in between the two tubular structures being attached or when bypassing.
Alternatively, either the braid or the malecot can have a permanent set put into in so that it is normally open with the larger diameter. In this case, when it is put into tension (usually from some inner (or outer) core wire or mandril), it collapses down to the diameter of the shaft of the device.
Alternatively, too much abrasive action on the surface of the mechanism(s) may be deleterious to the patient as well. In the case of the braided configuration, some smoothener may be required so that just the appropriate amount of friction is realized for effective obstruction removal. Further, the realized rigidity of any of the type of mechanism(s)s must be optimized for this removal in the particular application.
A radially collapsible tubular channel can also be fabricated from several materials and configurations. One preferred configuration is a multi-stranded braided device. The strands can be made of any material that would be useful for a particular application (polymers like polyester, nylon, Mylar, etc.) or, metal (stainless steel, Nickel Titanium Allow (Nitinol), platinum, etc.). Certainly, the potentially useful materials are not constrained to those materials listed. Additionally, the mechanism channel may be coated or encased in an elastomeric or other covering. Further, the mechanism channel may be fabricated of a material that will enlarge due to different forces than that of the braid mentioned previously. One other such force derived mechanism could be a material that swells/enlarges when put into a moist environment. Another such force derived mechanism is one that swells/enlarges when thermal energy is applied such as Two Way Shaped Memory Alloy (TWSMA) such as a Nickel-Titanium alloy. Yet, another may be one that occurs from an electrical, magnetic or other mechanical configuration/design/force.
The Tubular Braid ElementsThe mechanisms described above include an elongate tube; an elongate mandril inside the tube and an expandable tubular braid. The elongate mandril extends from the proximal end of the device to the distal end. The elongate tube usually extends from close to the proximal end of the device to close to the distal end. The distal end of the tubular braid is bonded to the distal end of the inner elongate mandril. The mandril may extend beyond the tubular braid. The proximal end of the tubular braid is bonded to the distal end of the elongate tube.
The braid may be open, but may be laminated or covered with a coating of elastic, generally inelastic, plastic or plastically deformable material, such as silicone rubber, latex, polyethylene, thermoplastic elastomers (such as C-Flex, commercially available from Consolidated Polymer Technology), polyurethane and the like. The assembly of tube, mandril and braid is introduced percutaneously in its radially compressed state. In this state, the outside diameter of the braid is close to the outside diameter of the elongate tube. This diameter is in the range of 10 to 500 mils, and usually 25 to 250 mils (i.e. thousandth of an inch) (0.25 to 12.7 mm, usually 0.64 to 6.4 mm). After insertion, moving the mandril proximally with respect to the tube expands the tubular braid.
The tubular braid is preferably formed as a mesh of individual non-elastic filaments (called “yarns” in the braiding industry). However, it can have some elastic filaments interwoven to create certain characteristics. The non-elastic yarns can be materials such as polyester, PET, polypropylene, polyamide fiber (Kevlar, Dupont), composite filament wound polymer, extruded polymer tubing (such as Nylon II or Ultem, commercially available from General Electric), stainless steel, Nickel Titanium (Nitinol), or the like so that axial shortening causes radial expansion of the braid. These materials have sufficient strength so that the tubular braided element will retain its expanded condition in the lumen of the body while removing the matter therefrom. Further, all expandable mechanisms described heretofore, can be manufactured using shape memory materials so that they are self expanding or even expandable when certain temperatures or thermal energies are delivered to the mechanisms. Such material characteristics can be accomplished with different programming methods such as, but not limited to Two Way Shape Memory (TWSM) alloys.
The braid may be of conventional construction, comprising round filaments, flat or ribbon filaments, square filaments, or the like. Non-round filaments may be advantageous to decrease the axial force required for expansion to create a preferred surface area configuration or to decrease the wall thickness of the tubular braid. The filament width or diameter will typically be from about 0.5 to 50 mils (0.013 to 1.3 mm), usually being from about 5 to 20 mils (0.13 to 0.51 mm). Suitable braids are commercially available from a variety of commercial suppliers.
The tubular braids are typically formed by a “Maypole” dance of yarn carriers. The braid consists of two systems of yarns alternately passing over and under each other causing a zigzag pattern on the surface. One system of yarns moves helically clockwise with respect to the fabric axis while the other moves helically counter-clockwise. The resulting fabric is a tubular braid. Common applications of tubular braids are lacings, electrical cable covers (i.e. insulation and shielding), “Chinese hand-cuffs” and reinforcements for composites. To form a balanced, torque-free fabric (tubular braid), the structure must contain the same number of yarns in each helical direction. The tubular braid may also be pressed flat to form a double thickness fabric strip. The braid weave used in the tubular braid of the present invention will preferably be of the construction known as “two dimensional, tubular, diamond braid” that has a 1/1 intersection pattern of the yarns which is referred to as the “intersection repeat”. Alternatively, a Regular braid with a 2/2-intersection repeat and a Hercules braid with an intersection repeat of 3/3 may be used. In all instances, the helix angle (that being the angle between the axis of the tubular braid and the yarn) will increase as the braid is expanded. Even further, Longitudinal Lay-Ins can be added within the braid yarns and parallel to the axis to aid with stability, improve tensile and compressive properties and modulus of the fabric. When these longitudinal “Lay-In” yarns are elastic in nature, the tubular braid is known as an elastic braid. When the longitudinal yarns are stiff, the fabric is called a rigid braid. Biaxially braided fabrics such as those of the present invention are not dimensionally stable. This is why the braid can be placed into an expanded state from a relaxed state (in the case of putting it into the compressive mode). Alternatively this could be a decreased/reduced (braid diameter decreases) state when put into tension from the relaxed state. When put into tension (or compression for that matter) the braid eventually reaches a state wherein the diameter will decrease no more. This is called the “Jammed State”. On a stress strain curve, this corresponds to increase modulus. Much of the engineering analyses concerning braids are calculated using the “Jammed State” of the structure/braid. These calculations help one skilled in the art to design a braid with particular desired characteristics. Further, material characteristics are tensile strength, stiffness and Young's modulus. In most instances, varying the material characteristics will vary the force with which the expanded condition of the tubular can exert radially. Even further, the friction between the individual yarns has an effect on the force required to compress and un-compress the tubular braid. For the present invention, friction should be relatively low for a chosen yarn so that the user will have little trouble deploying the engaging element. This is particularly important when the engaging element is located a significant distance from the user. Such is the case when the percutaneous entry is the groin (Femoral Artery for vascular interventions) and the point of engaging the engaging element is some distance away (i.e. the Carotid Artery in the neck). Similarly, this is true for long distances that are not vascular or percutaneous applications.
Coating of the Tubular BraidThroughout this disclosure, it is mentioned that the tubular braid may be coated with a material so that it may have no porosity or variable porosity within the individual filaments of the braid. This is an important configuration of the present invention and in certain instances may be critical (i.e. when a cancer is being removed from a small puncture hole, cancerous tissue must not be able to leak out through the walls of the tubular braid because the cancer may be seeded along the tract. This is important in the case of laparoscopic surgery as well. In fact, it may be important in many instances, not only where cancer is apparent.) One simple way to cover the tubular braid is to attach tubing over it. This has been done to prototypes of the present invention and works quite well. Elastomeric and inelastic coverings have been used. In some instances thermoplastic coverings were used and then heat and compression was applied along the tubular braid to melt it into the braid filaments. This works well. The braid was expanded from its original small diameter by sliding a mandril into the tubular braid. Once the braid is expanded, a liquid thermoset elastomer including, but not limited to silicone rubber, latex rubber, etc. or thermoplastic material including, but not limited to polyurethane was coated via a spray, dip, brush or other method. When the material cured, the mandril was removed and the tubular braid could be pulled on both ends (put into compression) and the tubular braid would go back to its original diameter. This is important for several reasons; the method described here allows the material to be applied within the filaments instead of over the filaments. This decreases the overall diameter of the tubular braid significantly as opposed to putting a covering over it. Further, the integrity of the material in between the filaments as opposed to over the filaments is increased because as the expandable channel is pushed forward, the material is hidden within the braid and hence doesn't see the forces of the tissue against it. Using a covering over the braid, the forces during the pushing are directly transmitted to the covering over the braid. Even further, the reliability and cost to manufacture are greatly improved. Even further and of extreme import is the fact that using a liquid that cures or a thermoplastic covering that is melted into the braid as opposed to covering it allows for varying the porosity along the tubular braid. This is extremely important in those cases where variable porosity is desired.
Device TestingPrototypes of the mechanisms were fabricated from the materials disclosed heretofore and of the dimensions commensurate with this disclosure.
Further, several different types of tubular braid were coated and/or covered with polymer elastomers and inelastomers as described heretofore. In one case, the braid was expanded to some diameter greater than the relaxed and smaller diameter. This was accomplished using a Teflon mandril. With the tubular braid in this somewhat expanded condition, the assembly was coated with liquid silicone rubber. When it dried, putting the system into tension so that the smaller original diameter was achieved again could elongate the assembly. It could then be put into compression and thusly shortened so that it would expand and the braid was covered so that there could be no holes in between the filaments of the braid. Further, the overall diameter of the tubular braid as not increased except for maybe 0.0001″ (0.0025 mm). Even further, trap devices were made whereby the silicone rubber was sprayed or painted onto the tubular braid when it was in the deployed/expanded condition. Once dried, the assembly could be un-deployed and then re-deployed with ease and without any holes between the filaments. Lastly, tubular braids were coated as described above with only partial coating to create variable porosity along the braid. Even further, the totally coated tubular braid was easy to puncture so that variable porosity was achieved as well. Further, multi-stranded braided tubing was braided using over 100 individual yarns made of thermoplastic materials and metallic materials. After braiding was completed, individual yarns were removed to change porosity. Alternatively when a combination of metal and thermoplastic yarns were used, the thermoplastic yarns were heated and melted away from the tubular mesh to change the pore size by leaving the metal or polymers with higher melt temperatures (or in the case of thermoset polymers, higher temperature resistant materials) leaving the metal or higher temperature resistant materials in place.
An exemplary device has the following characteristics:
Working Length: 10-500 cmWorking DiameterThe expandable mechanism has an outer diameter that ranges from 0.006″ to 0.450″ (0.15 mm to 1.14 cm), but can extend to smaller and larger sizes as technology and procedures require. The expandable mechanisms of the instant invention would be small in its un-deployed state in the range of 0.020-0.090 inches (0.51 mm to 2.3 mm) but would be expandable to diameters of with a tenfold increase or even larger.
Physical ConfigurationThe device of the instant invention may have conventional lubricious coatings to enhance introduction into the target body lumen, e.g. hyaluronic or other equivalent coatings. Further, the technician may apply a lubricious coating just before surgery. Also, a variety of drugs may be used with the device, as well as the above-described devices, for a variety of reasons such as reducing infection and/or rejection, and in the case of vascular situations, drug eluting mechanism can be added to help prevent stenosis or restenosis. Such drugs or compounds may be but are not limited to Sirolimus—an immunosuppressant drug usually used to prevent rejection in organ transplants—elutes from the stent into the vessel wall over the period when the scar tissue may be growing. Paclitaxel, a chemotherapy drug, may also be used. The Paclitaxel may gradually release directly into the coronary artery wall to prevent the restenosis process; this may be accomplished by embedding the material in the polymer as opposed to coating the device. The same may be true for Sirolimus.
As an advantage of the instant invention, the device will be less difficult to feed it to the desired location in the body due to its decreased size. Another advantage of the instant invention would be the ease with which bypassing or anastomosis can be accomplished. It can be done in a percutaneous fashion as opposed to an open, surgical procedure as well. Over the past decades, it has been proven that percutaneous intervention as compared to open surgical intervention has shown a great decrease in morbidity and mortality as well. This decreased difficulty will decrease cost due to time in the Operating Room (Operating Rooms costs are estimated in excess of $90 dollars per minute in the U.S.)
FIG. 63 illustrates the distal end of an anastomoticmedical device348 including atube350 having a tubularbraid anchor member352 secured to afirst end354 thereof.Device348 also includes anactuator355 extending throughtube350 past thesecond end356 oftube350, seeFIGS. 64 and 65, and connected to thedistal end358 ofanchor member352. A dilator360 passes throughtube350 and helps to guidemedical device348 through a relativelysmall opening362 intubular structure364 of a patient.FIG. 63 illustratesdevice348 passing into a blood vessel near thediseased obstruction366. Finally,device348 includes a guide wire368 passing centrally through dilator360. After being properly positioned, dilator360 and guide wire368 are removed andactuator355 is pulled, as indicated inFIG. 65, to causeanchor member352 to expand as shown inFIG. 66. If desired,anchor member352 could be self expanding or expandable on the application of, for example, heat.FIG. 67 illustratesanchor member352 includinghooks370 deployed to helpsecure anchor member352 in place.Hooks370 can be deployed by first pushing them distally and pulling them proximally to lock/hooktubular structure364 or by axially contractinganchor member352 to expose the hooks. Note that whiletubular structure364 is shown to be radially expanded whenanchor member352 is secured in place, such distention of the tubular structure may not be required.
An example oftubular mesh braid372 is shown inFIGS. 68 and 69.Braid372 can easily changed diameter by 1000% due to compression/tension forces as illustrated byarrows374,376 or due to a permanent set put intobraid372 during manufacturing. Alternatively, temperature change, or electrical, mechanical or magnetic forces, could be used to create the change in diameter as desired.FIG. 70 illustratestubular mesh braid372 including hooks378.Hooks378 can be deployed due to foreshortening ofbraid372. This foreshortening may occur with other expandable mechanisms disclosed above so that hook deployment can be accomplished using such other expandable mechanisms.
Anastomoticmedical device348 may havesecond end356 positioned externally of a patient's body and provide access to a single tubular structure. However, two anastomoticmedical device340 may be used in a patient and connected to two different tubular structures within a patient or may be used to bypass a portion of the same tubular structure. In either case, the second ends256 of the two anastomoticmedical devices348 are secured to one another in an appropriate fashion. The followingFIGS. 71-74 show various structures for joining the ends of a tubular structure of a patient; the structure may also be used to join second ends356 in appropriate cases.
FIG. 71 illustrates a tubular braided type of anastomoticmedical device380 covering the opposed ends382,384 of a severedtubular structure364.Ends382,384 are shown to be abutting but may be separated as well. The relaxed state ofmedical device380 is a smaller diameter state so thatdevice380 squeezestubular structure364 to maintain ends382,384 in place. If desired, the central portion ofdevice380 could be made to be liquid impervious or the entire device may be liquid impervious.FIG. 72 illustrates the use of a radially outwardly expanding anastomoticmedical device386 within the interior oftubular structure364 to join ends382,384.Ends382,384 may be spaced apart from one another or abutting, as indicated in dashed lines inFIG. 72. An appropriate portion ofdevice386 is typically liquid impervious to prevent leakage. If desired, a radially inwardly expandingdevice380 could be used on the outside oftubular structure364 and a radially outwardly expandingdevice386 could be used on the inside oftubular structure364 at the same junction.FIGS. 73 and 74 illustrate anastomoticmedical devices380,386 but with the addition ofhooks378 to help secure the anastomotic medical devices in place. Various membranes, films, wovens, and coatings could be used to aid with the function of the mechanisms disclosed above. Multiple porosities may also be advantageous for different applications. Drugs and other therapeutic agents may also be used in association with the above anastomotic devices.
FIG. 75 illustrates a variable porosityanastomotic device388 in the form of a straight tube.FIG. 76 illustrates a variable porosityanastomotic device390 in the form of a tapered tube. If such structures were placed inside the body channel, it may be desired to have the smaller pores at the central portion and the larger pores at the outer ends. The materials used for the various anastomotic medical devices described above could be all non-absorbable/degradable, all absorbable/degradable or a combination of the two depending upon the particular anastomotic application.
FIGS. 77 and 78 illustrate a malecot-type anastomotic device392 and radially contracted and radially expanded states.Device392 is shown having fourslits393, although two or more may suffice for radial expansion.FIGS. 79 and 80 illustrate the application of tension force, indicated byarrows376, and compression force, indicated byarrows374, todevice392 to place the device in radially contracted and radially expanded states
FIGS. 81 and 80 illustrate a variable porosityexpandable device394 having avariable porosity braid396 placeable in the radially contracted and radially expanded states ofFIGS. 81 and 82 by slidinginner tube398 withinouter tube400 as indicated by the arrows in the FIGS.
FIGS. 83 and 84 illustrate avariable diameter device402 in a radially contracted state inFIG. 83 and a radially expanded state inFIG. 84.Device402 includes aspiral ribbon404 of material constructed so that thelateral edges406 ofspiral ribbon404 are generally adjacent, that is close to one another or overlapping, to provide a generally continuous cylindrical surface so to approximate a solid cylinder.FIG. 85 is an end view of acoiled cylinder408.
FIGS. 86-87 illustrate a self expanding, expandable channelanastomotic device410 having twoslits412 formed inouter tube414. Theexpandable end416 ofdevice410 can be kept in its radially contracted state ofFIG. 86 by pushing oninner tube417, or allowed to assume its radially expanded state ofFIG. 87 by permittinginner tube417 to move in the direction of the arrow.FIG. 88 illustrates ananastomotic device418 that naturally assumes the radially expanded state ofFIG. 88 but is initially maintained in a radially contracted state by an outer tube, not shown. When expansion is desired, the outer tube is withdrawn or otherwise removed allowing expansion ofexpandable end416 to occur. Theanastomotic device420 ofFIGS. 89-91 is similar to the device ofFIGS. 86 and 87 but naturally assumes the radially contracted state ofFIG. 89. To place the device in a radially expanded state,inner tube417 is pulled as indicated inFIG. 90. Although not illustrated, various membranes, films, etc. can be used to fill in all or part of the spaces created byslits412 in the expandable ends416 of the devices.
Ananastomotic device422 is shownFIGS. 92 and 93 to include anouter tube424 and an inner, self expandingbraided member426.Braided member426 is initially constrained byouter tube424 that may be flexible and/or lubricated.Braided member426 may be permitted to expand by slidingouter tube424 in a retrograde fashion in the direction ofarrow428 or by pushing braidedmember426 in the direction ofarrow430, or both. Other types of structures, including a malecot such as shownFIGS. 86 and 87, a coiled tubular device such as shown inFIGS. 83 and 84, or a coiled cylinder device such as shown inFIG. 85, could be mechanized in such a fashion.
FIG. 94 illustrates an alternative to the tubularbraid anchor member352 ofFIGS. 63 and 66.Anastomotic device434 includes a tube436 having an innerexpandable mechanism438 or both an innerexpandable mechanism438 and an outerexpandable mechanism440 used to engage the periphery of opening362 intubular structure364.Expandable mechanisms438,440 may be tubular mesh braid as shown or some other type of expandable device, such as an inflatable balloon, a malecot, a coiled tubular device or coiled cylindrical device.
FIG. 95 illustrates atubular mesh braid444 mounted to the exterior of, for example, an endoscope or other elongate device within atubular structure364, for example the bowl or intestine.FIG. 96 illustratesbraid444 in an expanded state as result of pushing on the braid as indicated by the arrows. Advancing the endo device causestubular braid444 to contract down back on the endo device as shown inFIG. 97.
FIG. 98 shows a typicalsynthetic graft10 used in hemodialysis. The graft extends between avein12 and anartery14. Thegraft10 may be about thirty centimeters long with an inner diameter (I.D.) of 6 or 7 millimeters. Acatheter16 is inserted through the wall of the graft or vessel. Typically the catheter might have an outside diameter (O.D.) of 2.7 mm and an inner diameter (LD.) of 2.3 mm A malecottype expansion device18 is covered with a membrane20 (seeFIG. 101). When expanded, it serves to block the annular space between the outside wall of thecatheter16 and thegraft10. Asupport wire22 for abraided removal mechanism24 will typically have an outside diameter of about one mm and has an internal actuator rod26 (seeFIG. 99) of approximately 0.5 mm. Because of the simplicity of the design, this outside diameter could be smaller than 0.5 mm. InFIG. 98, the malecottype blocking device18 and thebraided removal device24 are both shown in their expanded state and are positioned so that retrograde or proximal movement of thesupport wire22 will pull the braided element in a proximal direction to push out whatever coagulated blood is between thebraided device18 and the distal end of the catheter into the catheter opening where it can be aspirated; thereby clearing the blockage in the graft or other vessel.
More particular one embodiment of this invention which has been partly tested, was designed for use in ahemodialysis graft10 having an I.D. of approximately six to seven mm. In that case, thecatheter16 has a 8 French O.D. (2.7 mm) and a 7 French I.D. (2.3 mm). Thesupport wire22 is a fairly standard movable core guide wire of 35 mils (that is, 0.35 inches, which is slightly under 1 mm). Theactuator rod26 in the support wire is approximately 15 mils and thus slightly under 0.5 mm. Thebraided element24 has an insertion diameter that is approximately one mm and expands to cover the seven mm diameter of the graft. In order to achieve this seven fold increase in diameter, the braided element has a length of 11 to 13 mm Thus the catheter has an annulus of about 2.3 mm around the support wire, through which annulus the blood occlusion is aspirated.
FIGS. 99 and 100 illustrate thesupport wire22 and braidedelement24 which constitute the occlusion engaging element that is moved proximal to push the occlusion into the catheter for removal. A preferredocclusion engaging element24 is a braided element. The braided material has to have a stiffness such that it will not collapse or fold under the pressure of the occlusion when this engaging element is being moved proximally. Yet the filaments that form the braid must be flexible enough to be moved between the two states as shown inFIGS. 99 and 100. Materials from polyester to stainless steel can be successfully used. A more detailed teaching of the considerations that go into the selection of the braided engaging element is set forth fiber on.
The distal tip of thebraided element24 is connected to the distal tip of theactuator rod26. The proximal edge of thebraided element24 is bonded to the distal end of thesupport wire22. Thus when theactuator rod26 is pushed in a distal direction relative to thewire22, the braided device is forced into its collapsed state shown inFIG. 99 and is available to be pushed through the catheter and through or around the occlusion which is to be removed. When this engagingelement24 has been fully inserted, theactuator rod26 is moved in a proximal direction causing thebraided element24 to take the expanded position such as that shown inFIG. 100 so that subsequent movement of theentire support wire22 will cause the braided element to move against the occlusion and push the occlusion into the distal end of the catheter. In some circumstances, thebraided element24 might be left as a braid with openings because the portions of the occlusion which may pass through the openings will be sufficiently smaller liquids so that they do not have to be removed. In other circumstances, it might be desirable to cover thebraided element24 with a membrane or film so that it becomes substantially impermeable. Further the membrane or film covering the engaging element will be helpful in preventing trauma to the inner walls of native tissue. Even further, this membrane may be helpful in opting the physical characteristics of the engaging element.
With reference toFIG. 98, it might be noted that when the braided element is pushed all the way down to one end of thegraft10, as shown inFIG. 98, and then expanded it will be expanding against a portion of the wall of the graft that is smaller than the bulk of the graft. However, as thesupport wire22 is pulled to move the braided occlusion removal element proximally, the braided occlusion element rides on the wall of the graft and will expand as the wall of the graft expands as long as tension is maintained on theactuator rod26.
There might be applications of the invention where the passageway involved is a tissue passageway such as a blood vessel or other channel within the body, where thisbraided element24 is expanded to nearly the diameter of the vessel so that when it is moved to push out an occlusion, it will avoid trauma to the wall of the vessel. Further, the membrane on the expanding element will aid in decreasing the trauma to native vessels as described above. In such a case, the engaging element (and the blocking element) may be used only as a ‘seal’ so that the obstruction may be removed or otherwise obliterated. This seal allows the rest of the vessel to be uncontaminated and provides for a ‘closed system’ for irrigation and/or aspiration and subsequent obliteration or removal of the obstruction
FIG. 101 illustrates thecatheter16 with themalecot18 in an expanded state on the distal end of the catheter. Amembrane20 is normally used in order to provide a complete blocking or sealing function. Further, themembrane20 may aid in locking the blocking element in a particular shape. This malecot type element is created by making longitudinal slits in the sidewall of the catheter (or an attachment bonded thereto) thereby creating links or wings that will expand when the distal end of the catheter is pushed in a proximal direction. The appropriate pushing of the proximal end of the catheter is achieved, as shown inFIG. 102, by aferrule30 which is a standard tip on astandard dilator28. Alternatively, thedilator28 may be a guide wire (which is usually much longer and flexible than a dilator) for remote obstruction removal. In such an application of the present invention, the guide wire would have a ferrule type mechanism that would act like the ferrule on the dilator. In this instance, the guide wire (with ferrule) would be inserted into the vessel to the obstruction. The catheter would then be pushed along the guide wire until it reached the ferrule which would normally be located near the distal end of the guide wire. At this point the wire would be pulled back, the ferrule would butt against the catheter and force out the blocking sealing element. The engaging element may be used with this blocking element and it could even be the ferruled wire as well.
It should be noted that the retention catheter described in U.S. Pat. No. 3,799,172 issued on Mar. 26, 1974 to Roman Szpur illustrates a structure that is similar to themalecot type device18 illustrated inFIG. 101; although in that patent it is used as a retention device whereas in this invention it is used as a blocking element.
This blockingelement18 is often called a malecot in the industry. It should be understood herein that the term malecot is used to refer in general to this type of multi-wing device.
More specifically, as shown inFIG. 102, thecatheter16 together with adilator28 having an expandedtip30 which is a ferrule is inserted into avessel32 such as the graft shown inFIG. 98. Thecatheter16 anddilator28 are inserted close to theocclusion34 and then thedilator28 is removed. Proximal motion of thedilator28 causes thetip30 to contact the distal end of thecatheter16 forcing the distal end of the catheter to put pressure on the malecot wings creating the expansion shown inFIG. 103 (and also schematically shown inFIG. 98). Once this expansion has occurred, the dilator with its tip can be removed from the catheter (as shown inFIG. 103).
What then occurs is shown inFIGS. 104 and 105. As shown inFIG. 104, thesupport wire22 with itsbraided removal element24 is inserted in the collapsed state so that it passes through or around theocclusion34. It should be noted that thesupport wire24 may be inserted prior to the blocking catheter being inserted or after the catheter is inserted (the latter of which is illustrated in the figures). Most of the occlusions to which this invention is directed such as congealed blood in a graft will permit asupport wire22 to pass through it because the consistency is that of viscous material which can be readily penetrated. Alternatively, if the occlusion is a non viscous material such as a stone, plaque, emboli, foreign body, etc. thesupport wire22 is small enough to be passed around the occlusion. Once thebraided element24 is on the distal side of theocclusion34, theactuator rod26 is pulled creating the expanded state for the braided device. Accordingly, distal movement of the entire support wire will cause the expanded braided device to move against the occlusion and force it into the catheter for removal with or without aspiration. When removal of obstructions that are located some distance array from the point of access into the body such as the carotid artery via a groin access thewire22 would likely be inserted first. In this case the support are22 with its expandingelement24 may be used as a guide wire to guide the catheter to the preferred location. Of further import is that the blocking element and the engaging element may be used without any relative motion once deployed. Such is the case when irrigation and/or aspiration is used for the obstruction removal In this case the two elements can be used as seals against the tubular inner walls on both sides of the obstruction whereby the obstruction is removed from that ‘sealed’ space with the use of aspiration, irrigation, or both. Further other means of obliterating the obstruction within this ‘sealed’ space may be employed. Some of those means are, but are not limited to the addition of dissolving agents, delivery of energy such as ultrasound, laser or light energy, hydraulic energy and the like.
The Tubular Braid Engaging ElementThe engaging apparatus includes an elongate tube; an elongate mandril inside the tube and an expandable tubular braid. The elongate mandril extends from the proximal end of the device to the distal end. The elongate tube extends from close to the proximal end of the device to close to the distal end. The distal end of the tubular braid is bonded to the distal end of the inner elongate mandril. The mandril may extend beyond the tubular braid. The proximal end of the tubular braid is bonded to the distal end of the elongate tube.
The braid may be open, but may be laminated or covered with a coating of elastic, generally inelastic, plastic or plastically deformable material, such as silicone rubber, latex, polyethylene, thermoplastic elastomers (such as C-Flex, commercially available from Consolidated Polymer Technology), polyurethane and the like. The assembly of tube, mandril and braid is introduced percutaneously in its radially compressed state. In this state, the outside diameter of the braid is close to the outside diameter of the elongate tube. This diameter is in the range of 10 to 50 mils, and usually 25 to 40 mils (i.e. thousandth of an inch). After insertion, the tubular braid is expanded by moving the mandril proximally with respect to the tube.
The tubular braid is preferably formed as a mesh of individual non-elastic filaments (called “yarns” in the braiding industry). But it can have some elastic filaments interwoven to create certain characteristics. The non-elastic yarns can be materials such as polyester, PET, polypropylene, polyamide fiber (Kevlar, DuPont), composite filament wound polymer, extruded polymer tubing (such as Nylon II or Ultem, commercially available from General Electric), stainless steel, Nickel Titanium (Nitinol), or the like so that axial shortening causes radial expansion of the braid. These materials have sufficient strength so that the engaging element will retain its expanded condition in the lumen of the body while removing the obstruction therefrom.
The braid may be of conventional construction, comprising round filaments, flat or ribbon filaments, square filaments, or the like. Non-round filaments may be advantageous to decrease the axial force required for expansion to create a preferred surface area configuration or to decrease the wall thickness of the tubular braid. The filament width or diameter will typically be from about 0.5 to 25 mils, usually being from about 5 to 10 mils. Suitable braids are commercially available from a variety of commercial suppliers.
The tubular braids are typically formed by a “Maypole” dance of yarn carriers. The braid consists of two systems of yarns alternately passing over and under each other causing a zigzag pattern on the surface. One system of yarns moves helically clockwise with respect to the fabric axis while the other moves helically counter-clockwise. The resulting fabric is a tubular braid. Common applications of tubular braids are lacings, electrical cable covers (i.e. insulation and shielding), “Chinese hand-cuffs” and reinforcements for composites. To form a balanced, torque-free fabric (tubular braid), the structure must contain the same number of yarns in each helical direction. The tubular braid may also be pressed flat so as to form a double thickness fabric strip. The braid weave used in the tubular braid of the present invention will preferably be of the construction known as “two dimensional, tubular, diamond braid” that has a 1/1 intersection pattern of the yarns which is referred to as the “intersection repeat”. Alternatively, a Regular braid with a 2/2 intersection repeat and a Hercules braid with an intersection repeat of 3/3 may be used. In all instances, the helix angle (that being the angle between the axis of the tubular braid and the yarn) will increase as the braid is expanded. Even further, Longitudinal Lay-Ins can be added with the braid yarns and parallel to the axis to aid with stability, improve tensile and compressive properties and modulus of the fabric. When these longitudinal “Lay-In” yarns are elastic in nature, the tubular braid is known as an elastic braid. When the longitudinal yarns are stiff, the fabric is called a rigid braid. Biaxially braided fabrics such as those of the present invention are not dimensionally stable. This is why the braid can be placed into an expanded state from a relaxed state (in the case of putting it into the compressive mode). Alternatively this could be a decreased/reduced (braid diameter decreases) state when put into tension from the relaxed state. When put into tension (or compression for that matter) the braid eventually reaches a state wherein the diameter will decrease no more. This is called the “Jammed State”. On a stress strain curve, this corresponds to increase modulus. Much of the engineering analysis concerning braids are calculated using the “Jammed state” of the structure/braid. These calculations help one skilled in the art to design a braid with particular desired characteristics. Further, material characteristics are tensile strength, stiffness and Young's modulus. In most instances, varying the material characteristics will vary the force with which the expanded condition of the tubular can exert radially. Even further, the friction between the individual yarns has an effect on the force required to compress and un-compress the tubular braid. For the present invention, function should be relatively low for a chosen yarn so that the user will have little trouble deploying the engaging element. This is particularly important when the engaging element is located a significant distance from the user. Such is the case when the percutaneous entry is the groin (Femoral Artery for vascular interventions) and the point of engaging the engaging element is some distance away (i.e. the Carotid Artery in the neck). Similarly, this is true for long distances that are not vascular or percutaneous applications.
Other CommentsAn important consideration of the invention described herein is that the support wire with its expanding element can be fabricated with a very small diameter. This is important because it allows an optimally large annular space between the wire and the inside of the catheter for maximum obstruction removal. Previous engaging elements have been used that use a balloon for the engaging element. This balloon design requires a larger shaft diameter than that of the present invention. Hence in these previous devices the annular space is not maximized as in the present invention. The term wire is used to refer to the support portion of the removal device. The material of the wire need not necessarily be metal. Further, it may be desirable to use a ‘double’ engaging element (i.e. two braided or malecot expanding elements separated a distance appropriate to entrap the occlusion) in the case for example where the occlusion is desired to be trapped in the vessel. The term wire is used herein to refer to a dual element device having a shell component and a core or mandril component which are longitudinally moveable relative to one another so as to be able to place the braided occlusion engaging element into its small diameter insertion state and its large diameter occlusion removal state.
Although the blocking element is described as a multi-malecot type of device, it should be understood that the blocking element may be designed in various fashions which are known in the art. See, for example,FIGS. 106 and 107. As another example, an appropriately designed braid arrangement could be used as the blocking element. In that case, the catheter may have to be a dual wall catheter in which the inner and outer annular walls are able to move relative to one another in a longitudinal direction so as to place the braid used as a blocking element in its small diameter insertion state and its large diameter blocking state. Alternatively, it may be a single wall similar in design to the malecot style blocking element described previously.
The particular embodiment disclosed was designed for an application to remove congealed blood in a dialysis graft. For some applications, like removing clots from remote vascular areas, the blocking mechanism and engaging elements may be used only as distal and proximal seals around the device to be removed so that the clot or other obstruction can be removed with aspiration or can be obliterated with some therapy such as a chemical dissolving agent or acoustical energy or lithotripsy and the like. The residual obstruction in that case would be aspirated from the tubular catheter.
It should be further understood that there might be a situation in which the blocking element or even the occlusion engaging element would be provided to the physician in a normal expanded state so that when the device is deployed, it would, through plastic memory or elastic memory, automatically snap into its expanded state.
The Tissue Removal AssemblyFIGS. 108A-108C illustrate the use of atissue removal assembly102.Tissue removal assembly102 includes asupport shaft104 passing through anintroducer sheath105 extending from ahandle106. Thedistal portion108 ofshaft104 has a pair oftissue separation wires110 mounted thereto.Wires110 are movable from a retracted state ofFIG. 108A to a fully extended state ofFIG. 108C by moving aslide112 mounted to handle106 as indicated inFIGS. 108A-108C.Wires110 are typically made of tungsten or stainless steel and may have a round, rectangular or other cross-sectional shape depending upon the type of tissue and other matter expected to be encountered. U.S. Pat. No. 6,221,006 andProvisional Applications 60/154,394 (filed Sep. 17, 1999 and entitled Oncological Apparatus and Method for Use) and 60/200,546 describe various tissue separation elements.Wires110 are coupled to anenergy source114 to supplywires110 with appropriate energy to aid the cutting or other separating actions of the wires, including electrical, RF, vibrational, electromagnetic, etc. Together, handle106 andenergy source114 constitute a wire tissueseparation element driver116 because both act to help movewires110 throughtissue118 beneath askin surface120 of the patient.
Appropriate sensors122 are mounted to one or more ofwires110 andshaft104.Sensors122 could be portions ofwires110 themselves.Sensors122 may include strain gauge sensors, pressure sensors, temperature sensors, etc.Sensors122 are coupled to afeedback device124 throughsheath105;feedback device124 is connected toenergy source114 to ensure thatenergy source114 provides an appropriate level of energy towires110.
Assembly102 is used to percutaneously access atarget site126 through anaccess site128 inskin surface120 while in the retracted state. Thetip130 ofshaft104 is positioned distally of thetarget tissue mass132. In some situations it may be desirable to passtip130 directly throughtarget tissue mass132 while in other situations it may be desirable to haveshaft104 pass to one side oftarget tissue mass132 or proximal to the tissue mass as inFIGS. 114A-116D. Once properly positioned, which is preferably accomplished with the aid of remote visualization techniques, such as x-rays, ultrasound, etc., slide112 is moved in a distaldirection causing wires110 to arc outwardly from the retracted state ofFIG. 108A, through the intermediate extended state ofFIG. 108B and to the fully extended state ofFIG. 108C.Wires110 are preferably energized, typically by heating using resistance or RF heating techniques, aswires110 pass throughtissue118. This is very important whenwires110 pass throughtarget tissue mass132 and the target tissue mass contains, or possibly contains, cancerous or other diseased tissue. By appropriately energizingwires110, thetissue wires110 pass through is, for example, cauterized so that no viable diseased tissue is pulled along with the radially outwardly expanding wires; this helps to keep the healthy tissue surroundingtarget tissue mass132 free from viable diseased tissue. In addition to heating or vaporizing the tissue,tissue removal assembly102 may be provided with vibrational, reciprocating or other mechanical energy to help passage ofwires110 throughtissue118.
Once fully expanded,tissue removal assembly102 is rotated, typically by the user manually grasping androtating handle106. If desired, a motorized or other non-manual rotation ofassembly102 could be provided for.Sensors122 provide appropriate information tofeedback device124 so to ensure a proper amount of energy is supplied towires110 to, among other things, ensure proper cauterization of the tissue aswires110 are moved readily outwardly while not overly damaging the tissue. Therefore, ifwires110 cease to be driven and thus stop moving through the tissue, feedback can result in a halt in the supply of energy towires110. Once in the fully extended state ofFIG. 108C, the amount of energy supplied towires110 may not need to be as great as when, for example,wires110 pass through only healthy tissue.
In the embodiment ofFIGS. 108A-108C twowires110 are used. This causestarget tissue mass132 to be cut away from the surrounding tissue in two contiguous tissue masses. If desired, only asingle wire110 or more than twowires110 could be used. The number of wires may be limited to, for example, 3 or 4 so that the sections removed are large enough to be identifiable. However, if one were to put additional wires into the assembly, even if only one wire was used for severing the tissue, the additional wires may help with removal of the tissue as they may be used to encapsulate the tissue. Using the method described with respect toFIGS. 108A-108C, the entiretarget tissue mass132 may be removed in a simultaneous manner. This aspect of the invention will be described in more detail below with reference toFIGS. 111A-111D. All or part of the procedure, such as expanding, cutting, rotating, energizing, etc., could be automated.
FIG. 109 illustrates asleeve136 used to help prevent seeding of atissue track138 extending betweenaccess site128 andtarget site126.Protective sleeve136 is positioned alongtissue track138 and has adistal opening140, preferably positioned adjacent to or withintarget site126, and anopen interior142.Target tissue144 is moved fromtarget site126 throughopening140 and intoopen interior142.FIG. 109 illustrates this having been accomplished using atissue engagement device145 having a radiallyexpandable mesh device146 at the distal end of ashaft148.Mesh device146 is of a type which can be movable from a generally cylindrical orientation, not shown, to the radially extended configuration shown inFIG. 109 by pushing the distal ends of the cylindrical mesh material towards one another. Examples of this type of mesh structure can be found in U.S. Pat. No. 6,179,860 and inProvisional Application 60/200,546. Other methods and devices for movingtarget tissue144 fromtarget site126 intointerior142 can also be used. Alternatively, the end ofsleeve136 could be used to sever the tissue whilesleeve136 is moved forward and a cutting/separating snare, seeFIGS. 115A-115F, could separate the distal side of the tissue.Target tissue144 can then be removed from the patient by either leavingprotective sleeve136 in place and sliding the target tissue out through the openedproximal end150 ofsleeve136 or by removing the entire structure, that isprotective sleeve136,mesh device146,shaft148 andtarget tissue144 therewith, fromtissue track138 of the patient. Suction may also be used to remove tissue. Removed tissue may be analyzed to see if additional tissue needs to be removed.
Access to avoid152 within a patient can be maintained by placingsleeve136 alongtissue track138 and leaving it in place. This method may be accomplished after removal of, for example, a biopsy specimen or an entire suspect tissue mass. This provides convenient and accurate re-access to void152. Such re-access may be used, for example, when additional tissue samples are needed, therapeutic agents (including heat treatment agents, mechanical treatment agents, chemical agents and radioactive agents) need to be delivered to void152, a prosthesis is to be implanted intovoid152, or for other reasons. See the discussion below with reference toFIGS. 117A-117C.
FIGS. 110A-110H illustrate the percutaneous removal oftarget tissue144 fromtarget site126. A hollow, radially expandable/collapsibletubular shaft154 is passed alongtissue track138 when in a radially collapsed condition as shown inFIG. 110A.FIG. 110B illustrates the introduction of atubular enlarger156 including aconical tip158 mounted to the distal end of ashaft160 and a stabilizingsleeve162 extending proximally fromconical tip158. As illustrated inFIGS. 110B and 110C, pushingenlarger156 throughshaft154 causes the shaft to radially enlarge along its length; stabilizingsleeve162 resists the tendency ofshaft154 to radially collapse. Oncesleeve162 is properly positioned withinshaft154,shaft160 andtip158 therewith are removed from withinsleeve162 as shown inFIG. 110D. Also,FIG. 110D illustrates the positioning of atissue engagement device145 to help draw a sample oftarget tissue144 into theinterior164 ofsleeve162 as suggested inFIGS. 110D and 110E.
At this point a sample of thetarget tissue144 may be removed from the patient by simultaneously removingshaft154 in its enlarge diameter form,sleeve162 anddevice145 as a unit. Alternatively, stabilizingsleeve162 may be removed asdevice145 pullstissue144 intoshaft154 whileshaft154 remains in place. This suggested inFIGS. 110E and 110F and permitsshaft154 to return towards its initial, radially contracted condition thus causing the tissue sample housed therein to be radially compressed. The collectedtarget tissue144 remains withinshaft154 whensleeve162 is removed fromshaft154 andmesh device146 is collapsed (seeFIG. 110F).Shaft154 then naturally assumes a smaller diameter condition as shown inFIGS. 110F and 110G which permitsshaft154 and the target tissue therein to be removed throughaccess site128 as shown inFIGS. 110G and 110H. In this way the size ofaccess site128 may be smaller than the original size oftarget tissue144.Device145 may remain withinshaft154 during this removal from the patient, ordevice145 may, as suggested inFIGS. 110G and 110H, be removed fromshaft154 along withsleeve162. Alternatively,mesh device146 may not be required as mentioned above.
Theentire shaft154 was enlarged in the embodiment ofFIGS. 110A-110H. If desired, only the part ofshaft154 within the patient may need to be expanded. This would reduce the maximum size whichaccess site128 is forced to assume, even if only temporarily. The following U.S. Pat. Nos. show radially-expanding dilators: 5,183,464; 5,431,676; 5,454,790.
FIGS. 111A-111D illustrate a method for percutaneously removing an entire tissue mass containingtarget tissue144. Atissue removal assembly166 includes asheath168 extending from aproximal end adapter170 and passes through anaccess site128 and alongtissue track138.Sheath168 houses atissue engagement device145, shown inFIG. 111A, after having passed by or throughtarget tissue144 and manipulated to causemesh device146 to assume a radially expanded condition. Next, atubular mesh device172, or other suitable mechanism, is used to surroundtarget tissue144.Device172 is of the type in which a tubular mesh material having an open distal end expands radially outwardly as it is compressed axially. That is, the resistance to the axialmovement mesh device172 causes it to contract axially and expand radially to assume the generally funnel-shaped configuration ofFIG. 111B. As shown inFIG. 111B,mesh device146 acts as a blocking element andmesh device172 acts as a removing element. Togetherdevices146,172 at least substantially surround, and preferably fully surround or envelope,target tissue144.
The entire suspect tissue mass, that is the mass includingtarget tissue144 and an amount of surrounding tissue (or only a portion oftarget tissue144, such as for biopsy), can be removed throughaccess site128. To help prevent trauma to accesssite128 during such removal,mesh device146 andtubular mesh device172 are caused to contract radially, thus compressingtarget tissue144 into a smaller diameter mass for ease of removal from the patient. This is suggested inFIGS. 111C and 111D. The construction and use of structure similar todevice172 is described in U.S. Pat. No. 6,221,006 and Provisional Application No. 60/200,546. Note that the structure shown inFIGS. 108A-108C could be used tosevere target tissue144 so that the entire suspect tissue mass (or a part of the suspect tissue mass, such as for biopsy), that is includingtarget tissue144, may be simultaneously removed as two contiguous pieces from the patient along the tissue track. It is expected that the entire suspect tissue mass could be severed into at most four contiguous pieces and still be simultaneously removed in a useful condition for further testing and/or evaluation. One such structure could use the cutting device ofFIGS. 108A-108C plus a mesh material similar totubular mesh device172 which could be guided by expandedwires110 to surround the suspect tissue mass. As seen by comparingFIGS. 111B and 111C, the largest lateral dimension of the access opening128 is smaller than the largest lateral dimension of a suspect tissue mass prior to removal; radially or laterally squeezing the suspect tissue mass permits removal of the tissue mass with minimal trauma to the patient. The suspect tissue mass may be monitored for disease prior to, during and/or after removal from the patient.
FIGS. 112A-112D illustrate a targetmaterial removing device178 including asheath180 within which a pair oftissue engaging devices145 slidable pass.FIG. 12A illustratesdevice178 passing throughaccess site128, alongtissue track138 and to targettissue144 attarget site126. The first andsecond mesh devices146A,146B are placed at distal and proximal locations relative to targettissue144. Once in position,mesh devices146 are expanded as shown inFIGS. 112B and 112C so tobracket target tissue144.Mesh devices146A,146B in their expanded conditions are sized so to define a bracketedregion182 therebetween.Bracketed region182 is preferably sized to completely contain the tissue mass includingtarget tissue144. When so bracketed, the health professional can locatetarget tissue144 by virtue of the expandedmesh devices146. In oneembodiment mesh devices146A,146B are harder than the surrounding tissue so thattarget tissue144 within bracketedregion182 may be found by palpation. In addition, expandedmeshed devices146A,146B guide a surgeon in locating and excising the entire target mass using surgical techniques. The using of bracketing guides146A,146B is important becausetarget tissue144 is often difficult to differentiate from surrounding tissue both in appearance and in feel. After the surgeon has accessedtarget tissue144, guided by bracketingmesh devices146, the entiresuspect tissue mass184 can be removed as a single mass as suggested inFIG. 112D. It is expected that the device ofFIGS. 112A-112D may be useful in both percutaneous and open incisional situations. Note thatbracketing mesh devices146A and146B may be designed so that they are shaped like cones or funnels so that their opposed edges meet to sever and capturesuspect tissue mass184 therebetween.
FIG. 113A-113C show the use of essentially the same type of structure as inFIGS. 112A-112D but for a different purpose. In thiscase devices145 are used as locational elements. In the preferred embodiment both of the locational elements have radially expandable elements, such asmesh devices146, both of which are positioned distally oftarget tissue144. After removal oftarget tissue144, which may occur along withproximal device145B,device145A remains in place adjacent to the excisional site or void152 created by the removal oftarget tissue144. This may be used to help maintain void152 open to aid re-access to the site. Maintainingvoid152 open also permits insertion of a space-saving device or structure intovoid152. Instead of using two radially expandable elements as portions of the locational devices,locational device145A could be simply, for example, a catheter shaft in which with the distal end would remain at the distal end ofexcisional site152.
Turning now toFIGS. 114A-119C, with like reference numerals referring to like elements, further aspects of the invention, relating to intraoperative tissue treatment methods, will be discussed. The treatment methods are designed to be intraoperative, that is practiced closely following the removal of target tissue from a target site, typically within a patient's breast, leaving access to the target site, such asintroducer sheath105 being left alongtissue track138.
FIG. 114A illustrates a void190 attarget site126 being accessed by an expandableelement insertion device192 throughsheath105.FIG. 114B shows an expandedballoon194 at the distal end ofinsertion device192 in an expanded condition substantially fillingvoid190.Balloon194, or some other expandable element such as an expandable malecot196 (FIG. 114J) or an expandable braided element198 (FIG. 114K) may be expanded to a size greater that ofvoid190 thus expanding the void slightly. It may be desired to do this to compress the surrounding tissue to facilitate subsequent removal of a layer oftissue200 from surrounding theexpandable element194 or for other reasons. The tissue that creates void190 is tested to determine if all the target tissue, typically diseased tissue, has been removed. If it is determined that all of the target tissue has been removed, then the patient is closed in the usual fashion. However, there may be a need for access for additional or adjunctive therapy. Even further, another material or an implant may be placed inside the cavity prior to closing the cavity. Note that the step of determining whether all the target tissue has been removed may be accomplished before or afterexpandable element194 has been positioned withinvoid190.
FIGS. 114C-14H show one method of separatingtissue layer200 from the surroundingtissue118 by passage of aloop separator202, shown also inFIGS. 115A-115F, overinsertion device192 and throughsheath105.Loop separator202 includes asheath204 through which acutter wire206 passes. Aloop208 ofwire206 extends from thedistal end210 ofsheath204. As thedistal end210 ofsheath204 is moved distally,wire206 is manipulated so thatloop208 first gets larger in size and then gets smaller in size as the loop passes around expandedballoon194 thus separatingtissue layer200 from the surroundingtissue118. To aid the cutting action ofloop208, the loop may, for example, have sharpened or roughened edges or the loop may be energized, such as by heating, or be supplied with mechanical vibrational or oscillatory energy. Other methods for separatingtissue layer200 may include, for example, the use of radially expandable and rotatable cutter wires as illustrated inFIGS. 108A-108C, the use of a mesh cutter as is discussed below with reference toFIGS. 116A-116D, or the use of tissue separation structure as is illustrated inFIGS. 118A-118H. After separatingtissue layer200 from the surroundingtissue118,loop separator202 may be removed for the subsequent removal oftissue layer200 surrounding expandedelement194.FIG. 114F proposes the removal of tissue there200 and expandedelement194 throughintroducer sheath205 by the use of suction as indicated byarrow211.FIG. 114G suggests the use of a meshtype capturing mechanism213 to enveloptissue layer200 for removal from the patient.Capturing mechanism213 may be similar to thetubular mesh material212 discussed below with regard toFIGS. 116A-116D. Other types of capturing mechanisms may be used as well. In addition,loop separator202 may be left in place and removed withtissue layer200 during an appropriate procedure.
FIG. 114I illustrates, in simplified form, a cross-sectional view oftissue layer200 removed from the patient.Tissue layer200 comprises an inner, void-definingsurface201 and anouter surface203.Outer surface203 may be tested to check for the presence of target tissue so to determine if all the target tissue has been removed. Ifouter surface203 tests positive for the presence of diseased tissue, a determination must be made as to how to deal with the diseased tissue remaining within the patient and surrounding theenlarged void205 shown inFIG. 114H. One procedure may be to repeat the procedure using an enlargedexpandable element194 sized to fit withinenlarged void205. Other surgical or non-surgical techniques may be used as well. If it is determined that all of the target tissue has been removed, then the patient is closed in the usual fashion. However, there may be a need for access for additional or adjunctive therapy. Even further, another material or an implant may be placed inside the cavity prior to closing the cavity.
FIG. 116A illustrates the situation shown inFIG. 114B, that is withexpandable element194 expanded attarget site126, with the use of a tubular, radiallyexpandable mesh cutter212 toseparate tissue layer200 from surroundingtissue118.Mesh cutter212 is typically made of an electrically conducting metal or other material that will sever the tissue mechanically.Mesh cutter212 is constructed so that when placed in compression, the distal, cuttingedge214 tends to radially expand. This is suggested inFIG. 116A. The amount and rate of radial expansion ofcutting edge214 may be controlled by, for example, the use of a pull wire or loop along the cutting edge. Ascutter212 continues to move distally from between inner andouter tubes215,217,distal cutting edge214 is gradually pulled down to the closed condition ofFIG. 116C so thatmesh cutter212 completely envelopstissue layer200 to permittissue layer200, together withexpandable element194 therein, to be withdrawn simultaneously withmesh cutter212 as suggested inFIG. 116D. This procedure helps to ensuretissue layer200 is substantially intact for examination by the physician or other health-care professional.
Another intraoperative treatment method, which may advantageously take place following the removal of target tissue from a target site leaving access, typically usingsheath105, to void190 at the target site, relates to placing aflexible implant216 into the void through the sheath.FIGS. 117A-117C illustrate the placement of a bag-typeflexible implant216, made of non-bioabsorbable material, throughsheath105 and intovoid190 to at least substantially filling void.Implant216 may also be a bioabsorbable material, such as collagen or a gel, that is eventually replaced with tissue. Afterflexible implant216 is in place,sheath105 may be removed as suggested inFIG. 117C. By maintainingsheath105 in place after removal of tissue from the target site, the implant placement takes place in an efficient manner without the additional trauma and expense that would result if placed postoperatively. Other types of flexible implants, such as an implant that may be inflated once in place within the void, could be used. The flexible implant will typically be filled with a flowable, or at least a formable, material, such as a liquid, a gel, a granular material, or a combination thereof.Implant216 preferably substantially fills void190, that is fills at least about 60 percent ofvoid190, and may be sized to completely fill void190 or to overfill, and thus enlarge, void190, such as by about 20 percent or more.
A further intraoperative tissue treatment method using suction is disclosed inFIGS. 118A-118H.FIG. 118A illustrates asuction device220 passing throughskin surface120.Device220 has atubular body221 withsuction inlets222 at its distal end, the suction inlets positioned withinvoid190. Fluid, typically including liquid, gas and the occasional particles, is withdrawn throughsuction inlets222 so to collapsetissue118surrounding void190 to createcollapsed tissue224 attarget site126 as shown inFIG. 118B.Suction device220 has, in this embodiment, a radially expandable blockingelement226 at the distal end ofbody221. Blockingelement226, in this embodiment, comprises numerousindividual wires228 which can be directed out throughopenings230 formed at the distal end oftubular body221. Blockingelement226 is positioned distally ofcollapsed tissue224 attarget site226. Atissue separator assembly232, seeFIGS. 118C-118E, includes arotatable tube234 which passes overshaft221 until itsdistal end236 extends betweencollapsed tissue224 and blockingelement226. Once in position, awire tissue cutter238 extends radially outwardly as indicated by anarrow240 ofFIG. 118B;tube234 is then rotated as indicated byarrow242 so to cut a layer oftissue200 surroundingtarget site226. To help preserve the integrity oftissue layer200 during and subsequent to the removal of the tissue layer from the patient, a radially expandable,tubular mesh material244 is extended out from between anouter tube246 androtatable tube234 ofassembly232.Mesh material244 may be constructed similarly to the material described with regard toFIGS. 116A-116D so that it tends to expand radially outwardly when placed under compression. Theouter edge248 ofmesh material244 tends to follow the dissection plane between theouter surface203 oftissue layer200 and thesurrounding tissue118. Once in the position ofFIG. 118G, withouter edge248 adjacent to blockingelement226,assembly232 andtissue layer200 housed withinmesh material244 can be removed in unison as indicated inFIG. 108H withtissue layer200 substantially intact for subsequent examination.
FIGS. 114H and 118H each show anenlarged void205 and a relativelynarrow tissue track138. Thetissue118 is quite elastic and very often permits the removal of an enlarged mass along a relatively narrow tissue track, after which the elastic nature of the tissue tends to cause the tissue to return to its prestretched condition. If desired, a second, enlargedexpandable element194 may be placed in theenlarged void205. If theouter surface203 oftissue layer200 is found to contain diseased tissue, a second excisional procedure as described above or some other therapeutic procedure, may be accomplished if considered necessary or desirable. Ifouter surface203 is found not to contain diseased tissue,enlarged void205 may have a hemostatic, bioabsorbable implant inserted into the void; in some situations it may be desired to place aflexible implant216 intovoid205, especially whilesheath205 is maintained in place.
FIGS. 119A-119C show an alternative to the method ofFIGS. 118A-118H. Asuction device252 extends along the tissue track and hassuction inlets222 at its distal end. After at least partially collapsing the tissue surroundingsuction inlets222, seeFIG. 119B, a rotatingblade tissue cutter256 is used to createtissue layer200 attarget site26. Removal oftissue layer200 can be in a manner similar to that discussed above with regard toFIGS. 110A-113C and114A-114H.
Modification and variation can be made to the disclosed embodiments ofFIGS. 108A-119C. For example, blockingelement226 and/ormesh material244, as well as other structure, may be used to remove tissue surrounding an expandedexpandable element194. The methods and devices ofFIGS. 114A-116D may be used to removecollapsed tissue224 ofFIGS. 118B-118H. In some situations it may be necessary or desirable to temporarily enlargetissue track138, such as using the devices and methods ofFIGS. 110A-110C.
The Occlusion, Anchoring, Tensioning and Flow Direction ApparatusAlthough the instant invention ofFIGS. 120-123 relates to four basic embodiments, those being flow directed, anchoring, tensioning and occluding, the instant invention is submitted for prosecution because the four embodiments are so closely related. Further and equally important is that the mechanical configuration(s) for all four embodiments of the present invention are similar.
The device of the instant invention is used for intervention into the tubular channels (lumens) of the body including, but not limited to arteries, veins, biliary tract, urological tract, intestines, nasal passages, ear canals, etc. Further, it can be useful as a suturing anchor in places of the body including, but not limited to adhering the stomach or other intestine to the abdominal wall in the case of feeding gastrostomies, jejunostomies, etc. Other anchoring applications of the instant invention include MIS facelifts and the repair of ptotic breasts. Even further, the instant invention is used for the repair of aneurysms of other permanent vessel occlusions. Such other permanent vessel occlusions would have applicability for occlusion of tributaries of vessels for vessel harvesting. The instant invention is particularly convenient to use in an operating room, interventional suite, patients' bedside, in an emergency room environment or in any emergency situation. One preferred embodiment of the instant invention is that it is inserted into the tubular channel of the body to utilize the flow directed characteristics of the invention. Once the device is in a flow/differential pressure situation, the inner core, mandrel/wire/string/member is deployed (usually pulled by the physician outside the body) so that the umbrella/trap configuration on the distal portion of the device opens. At the same time, the distal portion of the device becomes ‘floppy’ in nature so that it will follow the tortuous paths of the lumen without causing deleterious complications normally realized with conventional guide wires where they inadvertently damage the inner wall of the vessel when trying to cross said tortuous paths. The device is then carried in the direction of flow or of lower pressure (or with any contractile forces that may exist).
Once the device is in the desired position within the body, the umbrella like mechanism may or may not be un-deployed. In this case, once the device is removed from the package and before insertion into the body, the mechanism on the distal portion of the guide wire may be unopened (normally closed).
Alternatively, the device could have a distal configuration that causes it be moved in the direction of flow or in the direction of less pressure (or with the contractile forces) at the time it is opened from the package (e.g. normally opened). In this case the device is placed in the motion situation in the tubular channel of the body and is carried to the desired location. In the normally open position, the device may be very floppy in nature so that it will easily travel through the lumen of the body due to the pressure differential/flow/contractile forces. Once in position, the mechanism at the distal portion of the device may or may not be closed by some other mechanical means by the technician outside the body. One way of undeploying the distal ‘umbrella’ mechanism is by re-inserting the inner core so that the expanded mechanism becomes small or in its radially compressed state. Another advantage of re-inserting the inner core wire into the outer ‘floppy’ tube would be to make the support wire somewhat stiff, facilitating the insertion of another device over, through or along side the support wire that is attached to the expandable mechanism. Further, the umbrella like mechanism could become enlarged so that it will anchor in the lumen to keep its desired position.
Possible configurations of the distal mechanism are varied. One such mechanism is a balloon that is inflated for flow and deflated when not required. Another configuration that could be used is a mechanism known as a malecot. This malecot is a common configuration used in catheters for holding them in place (in the case of feeding tubes in the intestines). It is usually a polymeric tube that has four slits diametrically opposed. When the distal tip of the malecot is put into compression (usually by pulling an inner wire or member), the four sides of the polymer are pushed outward so as to create a larger diameter on the distal tip. Alternatively, the normal configuration of the malecot could be an open configuration whereby, when put into tension (large or small), the malecot closes to come near to or equal to the diameter of the elongated member. This larger diameter is larger than the body length of the catheter or wire. Another alternative is one that is similar to the malecot, but uses a multi-stranded braid on the distal end. When the braid is put into compression, the braid is pulled together and it flares out to create a larger diameter only the distal end. Alternatively either the braid or the malecot can have a permanent set put into in so that it is normally open or of the larger diameter. In this case, when it is put into tension (usually from some inner core wire or mandrel) it collapses down to the diameter of the body of the wire or catheter. Even further, the expandable mechanism on the distal end of these devices could be programmed to be thermally sensitive so that they expand or contract when placed in desired thermal gradients. One such mechanism for ‘programming’ materials like this is known as Shaped Memory Alloys (SMA) or Two Way Shaped Memory Alloys (TWSMA). Another exemplary embodiment of the instant invention is that once the device is placed in its desired location the mechanism (usually near the distal portion of the device) is deployed to ‘lock’ or ‘anchor’ it in the desired position.
Another embodiment is the tensioning characteristic of the instant invention. When the device is in or near a desired location of the body, the distal mechanism is deployed so that it anchors or has a tendency not to move. In this configuration, the wire, catheter or other device can be put into tension that will allow the passage of another device over or with the inner support wire. Even further and discussed heretofore, the instant invention can be ‘detached’ from the support wire and act as a tubular channel occluder.
This anchoring mechanism may or may not be used with the other embodiments. Further, the flow/contractile force characteristic may or may not be used with the other embodiments. Even further, the tensioning characteristic may or may not be used with the other embodiments. Last, the occluder may be used independently of the other three. In other words, although the distal mechanism that is used for all four embodiments may be similar to one another, the separate four embodiments may be used alone or in combination with the other embodiments.
Turning now toFIG. 120-A, a preferred embodiment of the instant invention is illustrated using a schematic drawing. The radially compressed,smaller support wire301 is illustrated. Theshaft302 is a tubular outer shell where the inner wire ortube303 rests. Theinner tube303 is attached to the distal end of theannular braid304 at305. Theouter shell302 may be attached to the annular braid at306. In the case of the detachable occluder inFIG. 120-C, it may not be attached so that the occluder is set free in the desired location.
Referring now toFIG. 120-B, the inner tube orwire303 is moved relative to theouter shell302 as indicated by thearrow307. This relative motion causes theannular braid304 to expand radially as shown at308. The shapes shown in these figures show an ovoid shape, however the shape can vary significantly as described heretofore. Notice that there is a through lumen illustrated inside theinner tube303 and is further indicated at the distal tip of the assembly by309. This may or may not be required depending on the application.
Turning now toFIG. 120-C, the preferred embodiment of the instant invention as anoccluder310 is illustrated in the schematic.
Referring now toFIGS. 121-A and121-B, a schematic view of the annular or tubular braid is illustrated.FIG. 121-A illustrates the annular braid in its relaxed, smaller orcompressed state311.FIG. 121-B illustrates the annular braid in its expandedstate312. The expansion is achieved by putting the braid into a compressive mode and changing the overall length of the braid. This can also be accomplished with self expanding of the braid by programming it with thermal treatments or using SMA (Shaped Memory Alloys) or by using a thermal change to change the shape of the device with a technique known as TWSMA (Two Way Shape Memory Alloy).
Turning now toFIG. 122, a preferred embodiment is illustrated in a schematic view. This is the expandeddevice301 in place in a tubular channel of the body. This figure shows the instant invention as anchor and subsequent tensioner if so desired for the particular application. Further, it could be the preferred embodiment of a flow directed guide wire or device if there is flow in the tubular channel as indicated by thearrow313. The mechanisms of the preferred embodiment are shown here inFIGS. 122 & 123 inside a tubular channel. However, the preferred embodiment of the instant invention could be used for other anchoring as heretofore disclosed. This anchor could be used for closing percutaneous punctures in the femoral artery for example as well. This is a ubiquitous problem. By deploying the anchor on the inside of the puncture of the vessel (artery or vein), the puncture wound would seal faster. Further dehydrated collagen could be used to aid in this procedure. Even further, this anchor or occluder could be fabricated with bio-resorbable materials as required for the particular application.
Turning now toFIG. 123-A, a schematic illustration shows theoccluder314 in place in the vessel. This is accomplished by removing the support wire (inner wire ortube303 and outer shell302) as described heretofore.FIG. 123-B shows theinstant invention301 in its smaller condition as it is being passed into a vessel with ananeurysm315.FIG. 123-C illustrates theoccluder314 in position in the aneurysm thus providing a novel therapy to this dangerous disease.
In any of these instances, the ‘desired’ location of the device is usually determined using Image Intensification (Fluoroscopy, Ultrasound Imaging, MRI, etc.). Further, the location could be monitored using cameras or other visualization techniques.
The Tubular Braid ElementsThe apparatus of the instant invention includes an elongate tube; an elongate mandril inside the tube and an expandable tubular braid. The elongate mandril extends from the proximal end of the device to the distal end. The elongate tube usually extends from close to the proximal end of the device to close to the distal end. The distal end of the tubular braid is bonded to the distal end of the inner elongate mandril. The mandril may extend beyond the tubular braid. The proximal end of the tubular braid is bonded to the distal end of the elongate tube.
The braid may be open, but may be laminated or covered with a coating of elastic, generally inelastic, plastic or plastically deformable material, such as silicone rubber, latex, polyethylene, thermoplastic elastomers (such as C-Flex, commercially available from Consolidated Polymer Technology), polyurethane and the like. The assembly of tube, mandril and braid is introduced percutaneously in its radially compressed state. In this state, the outside diameter of the braid is close to the outside diameter of the elongate tube. This diameter is in the range of 10 to 500 mils, and usually 25 to 250 mils (i.e. thousandth of an inch). After insertion, moving the mandril proximally with respect to the tube expands the tubular braid.
The tubular braid is preferably formed as a mesh of individual non-elastic filaments (called “yarns” in the braiding industry). However, it can have some elastic filaments interwoven to create certain characteristics. The non-elastic yarns can be materials such as polyester, PET, polypropylene, polyamide fiber (Kevlar, DuPont), composite filament wound polymer, extruded polymer tubing (such as Nylon II or Ultem, commercially available from General Electric), stainless steel, Nickel Titanium (Nitinol), or the like so that axial shortening causes radial expansion of the braid. These materials have sufficient strength so that the expanding element will retain its expanded condition in the lumen of the body while removing the matter therefrom. Further, all expandable mechanisms described heretofore, can be manufactured using shape memory materials so that they are self expanding or even expandable when certain temperatures or thermal energies are delivered to the mechanisms. Such material characteristics can be accomplished with different programming methods such as, but not limited to Two Way Shape Memory (TWSM) alloys.
The braid may be of conventional construction, comprising round filaments, flat or ribbon filaments, square filaments, or the like. Non-round filaments may be advantageous to decrease the axial force required for expansion to create a preferred surface area configuration or to decrease the wall thickness of the tubular braid. The filament width or diameter will typically be from about 0.5 to 50 mils, usually being from about 5 to 20 mils. Suitable braids are commercially available from a variety of commercial suppliers.
The tubular braids are typically formed by a “Maypole” dance of yarn carriers. The braid consists of two systems of yarns alternately passing over and under each other causing a zigzag pattern on the surface. One system of yarns moves helically clockwise with respect to the fabric axis while the other moves helically counter-clockwise. The resulting fabric is a tubular braid. Common applications of tubular braids are lacings, electrical cable covers (i.e. insulation and shielding), “Chinese hand-cuffs” and reinforcements for composites. To form a balanced, torque-free fabric (tubular braid), the structure must contain the same number of yarns in each helical direction. The tubular braid may also be pressed flat to form a double thickness fabric strip. The braid weave used in the tubular braid of the present invention will preferably be of the construction known as “two dimensional, tubular, diamond braid” that has a 1/1 intersection pattern of the yarns which is referred to as the “intersection repeat”. Alternatively, a Regular braid with a 2/2 intersection repeat and a Hercules braid with an intersection repeat of 3/3 may be used. In all instances, the helix angle (that being the angle between the axis of the tubular braid and the yarn) will increase as the braid is expanded. Even further, Longitudinal Lay-Ins can be added within the braid yarns and parallel to the axis to aid with stability, improve tensile and compressive properties and modulus of the fabric. When these longitudinal “Lay-In” yarns are elastic in nature, the tubular braid is known as an elastic braid. When the longitudinal yarns are stiff, the fabric is called a rigid braid. Biaxially braided fabrics such as those of the present invention are not dimensionally stable. This is why the braid can be placed into an expanded state from a relaxed state (in the case of putting it into the compressive mode). Alternatively this could be a decreased/reduced (braid diameter decreases) state when put into tension from the relaxed state. When put into tension (or compression for that matter) the braid eventually reaches a state wherein the diameter will decrease no more. This is called the “Jammed State”. On a stress strain curve, this corresponds to increase modulus. Much of the engineering analyses concerning braids are calculated using the “Jammed State” of the structure/braid. These calculations help one skilled in the art to design a braid with particular desired characteristics. Further, material characteristics are tensile strength, stiffness and Young's modulus. In most instances, varying the material characteristics will vary the force with which the expanded condition of the tubular can exert radially. Even further, the friction between the individual yarns has an effect on the force required to compress and un-compress the tubular braid. For the present invention, friction should be relatively low for a chosen yarn so that the user will have little trouble deploying the engaging element. This is particularly important when the engaging element is located a significant distance from the user. Such is the case when the percutaneous entry is the groin (Femoral Artery for vascular interventions) and the point of engaging the engaging element is some distance away (i.e. the Carotid Artery in the neck). Similarly, this is true for long distances that are not vascular or percutaneous applications.
An exemplary device has the following characteristics:
a. Working Length:
i. 30-500 cm
b. Working Diameter:
i. The guide wire, catheter, endoscope or other device of the present idea has an outer diameter that ranges from 0.006″ to 0.315″, but can extend to smaller and larger sizes as technology and procedures require.
c. Physical Configuration:
i. The device of the present idea will have a predetermined shaped (probably circular in diameter of 6-10″) coiled in the package, “as supplied”. Alternatively the product/device may be supplied straight but may have a shape at the distal end. The distal end may be tapered to a smaller distal diameter. This tapering may occur in the distal 6-12″ of the device, but could occur over a greater length and there may be more than one taper along its length. Optionally, the device may have a shaped tip or a tip that may be malleable so that the user prior to introduction may shape it.
The device of the instant invention may have conventional lubricious coatings to enhance introduction into the target body lumen, e.g. hyaluronic or other equivalent coatings. Further, the user, prior to insertion may apply a lubricious coating. This may be extremely useful in the case of a reusable device (like an endoscope). As an advantage of the present idea, the device will be less difficult to feed it to the desired location in the body. Further difficulty will be greatly decreased for placement of other devices over or with the inner device. Even further, the instant invention will be less difficult to remain in the target location. This decreased difficulty will decrease cost due to time in the Operating Room (Operating Rooms costs are estimated in excess of $90 dollars per minute in the U.S.) or other environment. Additionally, the decrease in difficulty will aid in patient care and the potential in deleterious effects due to the inability to place the device in the appropriate position in the patient and keep it there or to place other devices with the present idea.
An exemplary device having an expanding ‘umbrella’ mechanism located on its distal tip is illustrated in the figures. This mechanism may be at the tip or somewhere else in the distal portion of the device. Additionally, this mechanism may be any of a number of mechanisms that will help aid in moving the device using the physiological environment of the body. Alternatively, this distal mechanism may be used for anchoring, flow direction, tensioning or occluding. In this particular embodiment, a distal portion of the device may not coiled and will thus retain the malleable or resilient characteristics typical of conventional devices.
Although the foregoing idea has been described in some detail by way of illustration and example, for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.
The disclosures of any and all patents, patent applications and printed publications referred to above are hereby incorporated by reference.
Description of Inventive AspectsThe following sets of descriptions describe various inventive aspects discussed above and shown in the attached drawings. Although these descriptions are similar to claims, they are not claims. The claims are found in the section of the application entitled CLAIMS.
A. First Set
1. A medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body comprising:
a catheter having a proximal catheter end and a distal catheter end and defining a lumen extending from the distal catheter end towards the proximal catheter end, the catheter adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body;
a first expandable and contractible, vessel-occluding element positioned distal of the distal catheter end;
a second expandable and contractible, annular-space-blocking element positioned between the first expandable and contractible element and the proximal catheter end; and
at least one of the first and second expandable and contractible elements comprising spaced apart structural members and a membrane associated therewith.
2. The medical device according to claim 1 wherein the second expandable and contractible element is positioned at and extends from the catheter distal end.
3. The medical device according to claim 1 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element.
4. The medical device according to claim 1 wherein the second expandable and contractible element comprises a membrane.
5. The medical device according to claim 1 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element and a membrane associated therewith.
6. The medical device according to claim 5 wherein the membrane covers the multiple wing, malecot type of expandable and contractible element.
7. The medical device according to claim 1 wherein the first expandable and contractible element comprises a braided element.
8. The medical device according to claim 1 wherein the first expandable and contractible element comprises spaced apart structural members.
9. The medical device according to claim 1 wherein the first expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
10. The medical device according to claim 1 wherein the second expandable and contractible element comprises spaced apart structural members.
11. The medical device according to claim 1 wherein the second expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
12. The medical device according to claim 1 wherein the first and second expandable and contractible elements comprises spaced apart structural members.
13. The medical device according to claim 1 wherein at least one of the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
14. The medical device according to claim 1 wherein the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
15. The medical device according to claim 1 wherein the first expandable and contractible element comprises a braided element covered with a membrane.
16. The medical device according to claim 1 wherein the first expandable and contractible element comprises a native vessel sealing element.
17. The medical device according to claim 1 wherein a chosen one of the first and second expandable and contractible elements is funnel-shaped when in an expanded state.
18. The medical device according to claim 1 wherein a chosen one of the first and second expandable and contractible elements has a longitudinally-extending opening to permit material to pass therethrough.
19. The medical device according to claim 1 wherein the first expandable and contractible element is movable relative to the second expandable and contractible element.
20. The medical device according to claim 1 wherein the membrane is impermeable.
21. The medical device according to claim 1 wherein the membrane is elastomeric.
22. A medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body comprising:
a catheter having a proximal catheter end and a distal catheter end and defining a lumen extending from the distal catheter end towards the proximal catheter end, the catheter adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body;
a first expandable and contractible, vessel-occluding element positioned distal of the distal catheter end;
a second expandable and contractible, annular-space-blocking element positioned between the first expandable and contractible element and the proximal catheter end; and
a chosen one of the first and second expandable and contractible elements being having a funnel-shaped surface, when in an expanded state, and having a longitudinally-extending opening to permit material to pass therethrough for receipt of material.
23. The medical device according to claim 22 wherein the second expandable and contractible element is positioned at and extends from the catheter distal end.
24. The medical device according to claim 22 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element.
25. The medical device according to claim 22 wherein the second expandable and contractible element comprises a membrane.
26. The medical device according to claim 22 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element and a membrane associated therewith.
27. The medical device according to claim 26 wherein the membrane covers the multiple wing, malecot type of expandable and contractible element.
28. The medical device according to claim 22 wherein the first expandable and contractible element comprises a braided element.
29. The medical device according to claim 22 wherein the first expandable and contractible element comprises spaced apart structural members.
30. The medical device according to claim 22 wherein the first expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
31. The medical device according to claim 22 wherein the second expandable and contractible element comprises spaced apart structural members.
32. The medical device according to claim 22 wherein the second expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
33. The medical device according to claim 22 wherein at least one of the first and second expandable and contractible elements comprises spaced apart structural members.
34. The medical device according to claim 22 wherein the first and second expandable and contractible elements comprises spaced apart structural members.
35. The medical device according to claim 22 wherein at least one of the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
36. The medical device according to claim 22 wherein the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
37. The medical device according to claim 22 wherein the first expandable and contractible element comprises a braided element covered with a membrane.
38. The medical device according to claim 22 wherein the first expandable and contractible element comprises a native vessel sealing element.
39. The medical device according to claim 22 wherein the first expandable and contractible element is movable relative to the second expandable and contractible element.
40. The medical device according to claim 22 wherein at least one of the first and second expandable and contractible elements comprises a balloon.
41. A medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body comprising:
a catheter having a proximal catheter end and a distal catheter end and defining a lumen extending from the distal catheter end towards the proximal catheter end, the catheter adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body;
a support element extending distally of the distal catheter end;
a first expandable and contractible, vessel-occluding element mounted to the support element and positioned distal of the distal catheter end;
a second expandable and contractible, annular-space-blocking element mounted to the catheter and positioned between the first expandable and contractible element and the proximal catheter end; a chosen one of the first and second expandable and contractible elements being having a funnel-shaped surface, when in an expanded state, and having a longitudinally-extending opening to permit material to pass therethrough for receipt of material; and
at least one of the first and second expandable and contractible elements comprising spaced apart structural members and a membrane associated therewith.
42. The medical device according to claim 41 wherein a portion of the support element is housed within the catheter.
43. The medical device according to claim 41 wherein a portion of the support element is slidably housed within the catheter.
44. The medical device according to claim 41 wherein the first expandable and contractible element comprises a braided element.
45. The medical device according to claim 41 wherein the first expandable and contractible element comprises a braided element covered with a membrane.
46. The medical device according to claim 41 wherein the first expandable and contractible element comprises a native vessel sealing element.
47. A medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body comprising:
a catheter having a proximal catheter end and a distal catheter end and defining a lumen extending from the distal catheter end towards the proximal catheter end, the catheter adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body;
a first expandable and contractible, vessel-occluding element positioned distal of the distal catheter end; and
a second expandable and contractible, annular-space-blocking device-occluding element positioned between the first expandable and contractible element and the proximal catheter end.
48. The medical device according to claim 47 wherein the second expandable and contractible element is positioned at and extends from the catheter distal end.
49. The medical device according to claim 47 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element.
50. The medical device according to claim 47 wherein the second expandable and contractible element comprises a membrane.
51. The medical device according to claim 47 wherein the second expandable and contractible element comprises a multiple wing, malecot type of expandable and contractible element and a membrane associated therewith.
52. The medical device according to claim 51 wherein the membrane covers the multiple wing, malecot type of expandable and contractible element.
53. The medical device according to claim 47 wherein the first expandable and contractible element comprises a braided element.
54. The medical device according to claim 47 wherein the first expandable and contractible element comprises spaced apart structural members.
55. The medical device according to claim 47 wherein the first expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
56. The medical device according to claim 47 wherein the second expandable and contractible element comprises spaced apart structural members.
57. The medical device according to claim 47 wherein the second expandable and contractible element comprises spaced apart structural members and a membrane associated therewith.
58. The medical device according to claim 47 wherein at least one of the first and second expandable and contractible elements comprises spaced apart structural members.
59. The medical device according to claim 47 wherein the first and second expandable and contractible elements comprises spaced apart structural members.
60. The medical device according to claim 47 wherein at least one of the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
61. The medical device according to claim 47 wherein the first and second expandable and contractible elements comprises spaced apart structural members and a membrane associated therewith.
62. The medical device according to claim 47 wherein the first expandable and contractible element comprises a braided element covered with a membrane.
63. The medical device according to claim 47 wherein the first expandable and contractible element comprises a native vessel sealing element.
64. The medical device according to claim 47 wherein a chosen one of the first and second expandable and contractible elements is funnel-shaped when in an expanded state.
65. The medical device according to claim 47 wherein a chosen one of the first and second expandable and contractible elements has a longitudinally-extending opening to permit material to pass therethrough.
66. The medical device according to claim 47 wherein the first expandable and contractible element is movable relative to the second expandable and contractible element.
67. The medical device according to claim 47 wherein the second expandable and contractible, device-occluding element comprises an artificial vessel-occluding element.
68. The medical device according to claim 47 wherein at least one of the first and second expandable and contractible elements comprises a balloon.
69. A medical device for the use in diagnosis and/or treatment of cardiovascular disease in the human body comprising:
a catheter having a proximal catheter end and a distal catheter end and defining a lumen extending from the distal catheter end towards the proximal catheter end, the catheter adapted for use in diagnosis and/or treatment of cardiovascular disease in the human body;
an expandable and contractible, annular-space-blocking element carried by the catheter at or near the distal catheter end;
the expandable and contractible element having a funnel-shaped surface, when in an expanded state, for receipt of material; and
the expandable and contractible element comprising spaced apart structural members and a membrane associated therewith.
70. The medical device according to claim 69 wherein the membrane is an impermeable membrane.
71. The medical device according to claim 69 wherein the membrane is elastomeric.
72. The medical device according to claim 69 wherein the expandable and contractible element comprises a braided element.
73. The medical device according to claim 69 wherein the expandable and contractible element comprises a braided element covered with the membrane.
74. The medical device according to claim 69 wherein the expandable and contractible element comprises a native vessel sealing element.
Second Set
1. An occluder for use in a body passageway comprising:
a catheter having a distal end,
a multi-wing blood flow blocking element positioned near the distal end of the catheter,
said multi-wing blood flow blocking element having a radially compressed insertion state and a radially expanded blocking state,
an actuator associated with said catheter to move said blood flow blocking element from said compressed state to said expanded state, and
said blood flow blocking element in said radially expanded blocking state having a generally funnel surface extending out from said distal end of said catheter.
2. The occluder of claim 1 further comprising an annular membrane around said wings of said blood flow blocking element.
3. The occluder of claim 1 wherein said multiwing blood flow blocking element is a malecot style device.
4. The occluder ofclaim 2 wherein said membrane is an elastomeric, impermeable membrane.
5. The occluder of claim 1 wherein said actuator extends, through said lumen, distal of said blood flow blocking element and when moved in a proximal direction, engages said blood flow blocking element to switch said blood flow blocking element from said retracted insertion state into said radially expanded blocking state.
6. The method of deploying an occluder in a body passageway comprising:
inserting a catheter into a body passageway, said catheter having a multi-wing blood flow blocking element,
providing said blood flow blocking element in a radially compressed state during said step of inserting,
radially expanding said blood flow blocking element into a radially expanded state extending to or near to the wall of the body passageway after said step of inserting,
said step of radially expanding including providing said expanded state with a generally funnel surface extending out from said distal end of said catheter, and
using said expanded state of said blood flow blocking element for blocking passage of material around the outside of said catheter.
7. The method according to claim 6 wherein said blood flow blocking element is a malecot-style blood flow blocking device covered with an annular elastomeric, impermeable membrane.
8. A method of capturing tissue in a body comprising:
inserting an elongate tubular member, having a lumen, a proximal end and a distal end, into a body,
providing a malecot-style tissue capture element in a radially compressed state during the step of inserting,
radially expanding the tissue capture element into a radially expanded state after the step of inserting, and
providing a proximal surface on said the capture element, the proximal surface extending out from the distal end of the elongate tubular member wherein the tissue is captured along the proximal surface.
9. The method according to claim 8 wherein the tissue capture element is generally funnel shaped when in the radially expanded state.
10. An occluder for use in a body passageway comprising:
a catheter having a distal end,
a blood flow blocking element comprising structural members which define openings therebetween, the blood flow blocking element positioned near the distal end of the catheter,
said blood flow blocking element having a radially compressed insertion state and a radially expanded blocking state,
an actuator associated with said catheter to move said blood flow blocking element from said compressed state to said expanded state, and
said blood flow blocking element in said radially expanded blocking state having a generally funnel surface extending out from said distal end of said catheter.
11. The occluder ofclaim 10 further comprising an annular membrane around said structural members of said blood flow blocking element.
12. The occluder of claim 11 wherein said blood flow blocking element is a malecot style device.
13. The occluder of claim 11 wherein said membrane is an elastomeric, impermeable membrane.
14. The occluder ofclaim 10 wherein said actuator extends, through said lumen, distal of said blood flow blocking element and when moved in a proximal direction, engages said blood flow blocking element to switch said blood flow blocking element from said retracted insertion state into said radially expanded blocking state.
15. A method of deploying an occluder in a body passageway comprising:
inserting a catheter into a body passageway, said catheter having a blood flow blocking element comprising structural members which define openings therebetween and an axially movable actuator operably coupleable to the blood flow blocking element,
providing said blood flow blocking element in a radially compressed state during said step of inserting,
moving the actuator thereby radially expanding said blood flow blocking element into a radially expanded state extending to or near to the wall of the body passageway after said step of inserting,
said step of radially expanding including providing said expanded state with a generally funnel surface extending out from said distal end of said catheter, and
using said expanded state of said blood flow blocking element for blocking passage of material around the outside of said catheter.
16. The method according to claim 15 wherein said blood flow blocking element is a malecot-style blood flow blocking device covered with an annular elastomeric, impermeable membrane.
17. A method of capturing tissue in a body comprising:
inserting an elongate tubular member, having a lumen, an actuator passing through the lumen, a proximal end and a distal end, into a body,
providing a tissue capture element in a radially compressed state during the step of inserting, the tissue capture element comprising structural members which define openings therebetween, the actuator operably coupleable to the tissue capture element,
moving the actuator thereby radially expanding the tissue capture element into a radially expanded state after the step of inserting, and
providing a proximal surface on said the capture element, the proximal surface extending out from the distal end of the elongate tubular member wherein the tissue is captured along the proximal surface.
18. The method according to claim 17 wherein the tissue capture element is generally funnel shaped when in the radially expanded state.
19. A medical instrument for use in a body comprising:
an elongate tubular member having a lumen and a distal end,
a blood flow blocking element comprising structural members which define openings therebetween, the blood flow blocking element positioned near said distal end of said elongate member,
an annular membrane around said structural members of said blood flow blocking element,
said blood flow blocking element having a radially compressed state and a radially expanded blocking state,
an actuator associated with said elongate member to move said blood flow blocking element from said compressed state and to said blocking state,
said blood flow blocking element in said radially expanded blocking state having a generally funnel shape surface extending from said distal end of said elongate tubular member.
20. The medical instrument of claim 19 wherein said membrane is an elastomeric, impermeable membrane.
21. The medical instrument of claim 19 wherein said actuator extends, through said lumen, distal of said blood flow blocking element and when moved in a proximal direction, engages said blood flow blocking element to switch said blood flow blocking element from said retracted compressed state into said radially expanded state.
22. An occluder for use in a body passageway comprising:
a catheter having a distal end,
a blood flow blocking element comprising structural members which define openings therebetween, the blood flow blocking element positioned near the distal end of the catheter, and
an annular membrane around said structural members of said blood flow blocking element,
said blood flow blocking element having a radially compressed insertion state and a radially expanded blocking state,
an actuator associated with said catheter to move said blood flow blocking element from said compressed state to said expanded state.
23. The occluder ofclaim 22 wherein said membrane is an elastomeric, impermeable membrane.
24. The occluder ofclaim 22 wherein said actuator extends, through said lumen, distal of said blood flow blocking element and when moved in a proximal direction, engages said blood flow blocking element to switch said blood flow blocking element from said retracted insertion state into said radially expanded blocking state.
25. The method of deploying an occluder in a body passageway comprising the steps of:
inserting a catheter into a body passageway, said catheter having a blood flow blocking element comprising structural members which define openings therebetween, the blood flow blocking element covered with an annular elastomeric, impermeable membrane, and an axially movable actuator operably coupleable to a distal portion of the blood flow blocking element,
providing said blood flow blocking element in a radially compressed state during said step of inserting, and
moving the actuator thereby radially expanding said blood flow blocking element into a radially expanded state extending to or near to the wall of the body passageway after said step of inserting, and
using said expanded state of said blood flow blocking element for blocking passage of material around the outside of said catheter.
26. The method of claim 25 wherein said step of radially expanding includes providing said expanded state with a generally funnel surface extending out from said distal end of said catheter.
27. The method of claim 25 wherein the actuator moving step comprises proximally pulling the actuator.
Third Set
1. A catheter/dilator assembly comprising:
a catheter assembly comprising:
- a catheter having a proximal catheter end, a distal catheter end, a lumen, and an outer catheter surface; and
- a material-directing element, movable between radially expanded and radially collapsed states, secured to and extending past the distal catheter end, the material-directing element having an axial length when in the radially collapsed state;
a dilator comprising a hollow shaft within the lumen of the catheter, the hollow shaft having an outer shaft surface, a proximal shaft end, a distal shaft end and a recessed region in the outer shaft surface at the distal shaft end;
the recessed region and the material-directing element being generally aligned with one another; a compression element covering the material-directing element to temporarily retain the material-directing element in a radially collapsed state; and
the recessed region sized for receipt of at least substantially the entire axial length of the material-directing element so to reduce the radial cross-sectional dimension of the assembly at the material-directing element.
2. The assembly according to claim 1 wherein the compression element comprises a sleeve slidable between a position covering the material-directing element and a position along the catheter between the proximal and distal catheter ends.
3. The assembly according to claim 1 wherein the material-directing element comprises a funnel element.
4. The assembly according to claim 3 wherein the funnel element comprises a braided funnel element.
5. The assembly according to claim 3 wherein the funnel element comprises an inflatable funnel element.
6. The assembly according to claim 3 wherein the funnel element comprises a malecot funnel element.
7. The assembly according to claim 1 wherein the compression element comprises a sleeve, the sleeve comprising distal and proximal portions, the distal portion covering the material-directing element and the proximal portion covering the distal catheter end.
8. The assembly according toclaim 7 wherein at least a part of the distal portion of the sleeve is sufficiently weak so that when the sleeve is pulled in a proximal direction to uncover the material-directing element, at least the part of the distal portion of the sleeve substantially expands as it passes over the distal catheter end.
9. The assembly according toclaim 7 wherein the distal portion has an outside diameter and the proximal portion has an inside diameter.
10. The assembly according to claim 9 wherein the outside and inside diameters are about equal to one another.
11. The assembly according to claim 9 wherein the catheter has an outside catheter diameter substantially equal to the outside diameter of the distal portion of the sleeve.
12. The assembly according to claim 9 wherein the outside diameter of the distal portion is within 25% of the outside diameter of the catheter.
13. The assembly according to claim 9 wherein the outside diameter of the distal portion is within 15% of the outside diameter of the catheter.
14. The assembly according to claim 9 wherein the outside diameter of the distal portion is within 10% of the outside diameter of the catheter.
15. The assembly according to claim 9 wherein:
the outside and inside diameters are about equal to one another;
the catheter has an outside catheter diameter substantially equal to the outside diameter of the distal portion of the sleeve and the inside diameter of the proximal portion of the sleeve; and
at least a part of the distal portion of the sleeve is sufficiently weak so that when the sleeve is pulled in a proximal direction to uncover the material-directing element, at least the part of the distal portion of the sleeve substantially expands as it passes over the distal catheter end.
16. The assembly according to claim 15 wherein said part of the distal portion comprises a weakened region.
17. The assembly according to claim 16 wherein the weakened region comprises a material separation region within the distal portion of the sleeve.
18. The assembly according to claim 16 wherein the weakened region comprises a reduced thickness region in the distal portion of the sleeve.
19. The assembly according to claim 8 further comprising a spacer sleeve slidably mounted on the outer catheter surface between the sleeve and the proximal catheter end, the spacer sleeve sized to help properly locate the distal portion of the sleeve over the material-directing element and the proximal portion of the sleeve over the distal catheter end.
20. The assembly according to claim 19 wherein the spacer sleeve is configured to permit the sleeve to be pulled proximally to a material-directing element deployed position so that the sleeve no longer covers the material-directing element.
21. The assembly according to claim 19 wherein the spacer sleeve comprises a yieldable sleeve portion that yields when the sleeve is pulled proximally to the material-directing element deployed position.
22. The assembly according toclaim 7 wherein the material-directing element comprises a funnel element.
23. A method for assembling a catheter/dilator assembly comprising:
selecting a catheter assembly comprising:
- a catheter having a proximal catheter end, a distal catheter end, a lumen, and an outer catheter surface; and
- a material-directing element, movable between radially expanded and radially collapsed states, secured to and extending past the distal catheter end, the material-directing element having an axial length when in the radially collapsed state;
inserting a hollow shaft of a dilator through the proximal catheter end and into the lumen of the catheter;
positioning a recess formed in the distal shaft end of the hollow shaft to underlie the material-directing element;
placing the material-directing element in the radially collapsed state; and
sliding a first sleeve in a proximal direction to a first position covering the distal shaft end of the dilator and over the material-directing element to maintain the material-directing element in the radially collapsed state.
24. The method according to claim 23 wherein the sliding step is carried out so that when the first sleeve is in the first position, a distal portion of the sleeve covers the funnel element and a proximal portion of the sleeve covers the distal catheter end.
25. The method according to claim 23 wherein the placing step comprises moving a second sleeve, slidably mounted on the outer catheter surface, in a distal direction to cover the funnel element.
26. The method according to claim 25 wherein the sliding step causes the second sleeve to move in a proximal direction to a third position on the outer catheter surface.
27. A method for removing material from a tubular structure within a body comprising:
selecting a catheter/dilator assembly comprising:
- a catheter assembly comprising:
- a catheter having a proximal catheter end, a distal catheter end, a lumen, and an outer catheter surface; and
- a material-directing element, movable between radially expanded and radially collapsed states, secured to and extending past the distal catheter end, the material-directing element having an axial length when in the radially collapsed state;
- a dilator comprising a hollow shaft within the lumen of the catheter, the hollow shaft having an outer shaft surface, a proximal shaft end, a distal shaft end and a recessed region in the outer shaft surface at or near the distal shaft end;
- the recessed region and the material-directing element being generally aligned with one another;
a sleeve comprising distal and proximal portions, the distal portion covering the material-directing element to temporarily retain the material-directing element in a radially collapsed state, the proximal portion covering the distal catheter end; and
the recessed region sized for receipt of at least substantially the entire axial length of the material-directing element so to reduce the radial cross-sectional dimension of the assembly at the material-directing element;
locating the material-directing element at a first target location within a lumen of a tubular structure;
uncovering the material-directing element to place the material-directing element in a radially expanded state with the material-directing element contacting an inner surface of the tubular structure;
causing material within the lumen to move into the catheter/dilator assembly; and
removing the catheter/dilator assembly from the body.
28. The method according to claim 27 wherein the locating step comprises:
positioning a tip of a guide wire at a second target location within the lumen of the tubular structure, the guide wire having a proximal end; and
passing the proximal end of the guide wire into the distal shaft end of the dilator and at least partially through the dilator; and further comprising
removing the guide wire from the body.
29. The method according to claim 28 wherein the guide wire positioning step comprises:
puncturing the tubular structure to access the lumen with a hollow needle;
passing the guide wire through the hollow needle until the tip of the guide wire is at the second target location; and
removing the needle leaving the guide wire in place.
30. The method according to claim 28 further comprising:
selecting a guide wire having a radially expandable and contractible element at the tip of the guide wire; and
placing the radially expandable and contractible element in a radially expanded state when the tip of the guide wire is at the second target location.
31. The method according to claim 30 wherein the causing element comprises:
creating a suction force between the catheter and the hollow shaft of the dilator; and
moving the material-directing element and the radially expandable and contractible element toward one another.
32. The method according to claim 31 further comprising:
sliding the sleeve distally to cover the material-directing element to place the material-directing element in a radially collapsed state prior to the catheter/dilator assembly removing step; and
placing the radially expandable and contractible element in a radially contracted state prior to the guide wire removing step.
33. The method according to claim 27 wherein the causing element comprises creating a suction force between the catheter and the hollow shaft of the dilator.
34. The method according to claim 27 further comprising sliding the sleeve distally to cover the material-directing element to place the material-directing element in a radially collapsed state prior to the catheter/dilator assembly removing step.
35. The method according to claim 27 wherein the locating step is carried out with the tubular structure comprising a blood vessel.
36. The method according to claim 27 wherein the locating step is carried out with the tubular structure comprising a graft.
37. A method for removing material from a tubular structure within a body comprising:
selecting a catheter/dilator assembly assembled according to claim 23 ;
locating the material-directing element at a first target location within a lumen of a tubular structure;
uncovering the material-directing element to place the material-directing element in a radially expanded state with the material-directing element contacting an inner surface of the tubular structure;
causing material within the lumen to move into the catheter/dilator assembly; and
removing the catheter/dilator assembly from the body.
38. A dilator assembly comprising:
an elongate dilator comprising proximal and distal portions, a dilator tip at the distal portion, and a dilator lumen extending from the dilator tip to at least a first position along the dilator;
the dilator comprising a guide wire pathway extending from a second position at the proximal portion of the dilator to the first position;
an opening in the dilator at the first position connecting the guide wire pathway and the dilator lumen; and
a flexible guide wire extending along the guide wire pathway, through the opening, through the dilator lumen and out of the dilator tip.
39. The assembly according to claim 38 wherein the guide wire pathway comprises a groove formed in the dilator.
40. A rapid exchange dilator assembly comprising:
a catheter comprising a catheter lumen extending between a distal catheter end and a proximal catheter end;
an elongate dilator, removably housed within the catheter lumen, comprising a proximal portion extending to a proximal dilator end, a distal portion extending to a dilator tip, and a dilator lumen extending from the dilator tip to at least a first position along the dilator;
the dilator comprising a guide wire pathway extending from the proximal portion of the dilator to the first position;
an opening in the dilator at the first position connecting the guide wire pathway and the dilator lumen;
a flexible guide wire, comprising a guide wire proximal end and a guide wire distal end, extending along the guide wire pathway, through the opening, through the dilator lumen and out of the dilator tip; and
the guide wire proximal end and the proximal dilator end are positioned proximally of the proximal catheter end, the guide wire distal end and the distal dilator end is positioned distally of the distal catheter end;
whereby when the assembly is at a desired position within a body, the dilator can be removed leaving the catheter and guide wire in position.
41. The assembly according to claim 40 wherein the catheter comprises:
a material-directing element, movable between radially expanded and radially collapsed states, secured to the distal catheter end.
42. The assembly according to claim 41 wherein the material-directing element comprises an expandable braid element.
43. The assembly according to claim 41 wherein the material-directing element comprises an expandable braid funnel element.
44. The assembly according to claim 41 wherein the material-directing element comprises an inflatable element.
45. The assembly according to claim 41 wherein the material-directing element comprises an inflatable funnel element.
46. The assembly according to claim 41 wherein the material-directing element comprises an expandable malecot element.
47. The assembly according to claim 41 wherein the material-directing element comprises an expandable malecot funnel element.
48. The assembly according to claim 40 wherein the catheter comprises:
outer and inner catheters, the inner catheter slidably mounted within the outer catheter, the outer and inner catheters comprising distal outer and inner catheter ends; and
a material-directing element, movable between radially expanded and radially collapsed states, secured to the distal outer and inner catheter ends.
49. The assembly according to claim 48 wherein the material-directing element comprises an expandable braid funnel element.
50. A method for providing access to a target site within a tubular structure of a patient, comprising:
positioning a distal catheter end of a first, guide catheter at a first position within a tubular structure of a patient;
passing a rapid exchange dilator assembly into the first catheter, the rapid exchange dilator assembly comprising a second catheter, the second catheter comprising a removable dilator, a guide wire and a second catheter lumen, the second catheter lumen housing the dilator and the guide wire;
removing the dilator from the patient leaving the second catheter and the guide wire within the patient; and
passing an operational device through the second catheter for performing a procedure at the target site.
51. The method according to claim 50 wherein the positioning step is carried out by:
placing a distal end of a second guide wire at a second position within the tubular structure;
passing the first catheter over the second guide wire; and
removing the second guide wire from the patient while leaving the first catheter within the patient.
52. The method according to claim 50 further comprising radially expanding a material-directing element, mounted to the second catheter, to a radially expanded state.
53. The method according to claim 50 further comprising radially expanding a material-directing funnel element, mounted to an extending from the second catheter, to a radially expanded state with the funnel element contacting an inner wall of the tubular structure.
54. The method according to claim 50 wherein the operational device passing step comprises passing a stent through the second catheter, and further comprising placing the stent at the target site.
55. The method according to claim 50 wherein the operational device passing step comprises passing a balloon catheter, comprising a balloon, through the second catheter, and further comprising expanding the balloon at the target site.
56. A method for providing access to a target site within a tubular structure of a patient, comprising:
selecting a rapid exchange dilator assembly comprising:
a catheter comprising a catheter lumen, extending between a distal catheter end and a proximal catheter end, and a material-directing element, movable between radially expanded and radially collapsed states, secured to the distal catheter end;
an elongate dilator, removably housed within the catheter lumen, comprising a proximal portion extending to a proximal dilator end, a distal portion extending to a dilator tip, and a dilator lumen extending from the dilator tip to at least a first position along the dilator;
the dilator comprising a guide wire pathway extending from the proximal portion of the dilator to the first position;
an opening in the dilator at the first position connecting the guide wire pathway and the dilator lumen;
a flexible guide wire, comprising a guide wire proximal end and a guide wire distal end, extending along the guide wire pathway, through the opening, through the dilator lumen and out of the dilator tip; and
the guide wire proximal end and the proximal dilator end position proximally of the proximal catheter end, the guide wire distal end and the distal dilator end position the distally of the distal catheter end;
positioning a distal catheter end of a guide catheter at a second position within a tubular structure of a patient;
passing the rapid exchange dilator assembly into the guide catheter;
removing the dilator from the patient leaving the catheter and the guide wire of the rapid exchange dilator assembly within the patient; and
passing an operational device through the catheter of the rapid exchange dilator assembly for performing a procedure at the target site.
57. The method according to claim 56 wherein the positioning step is carried out by:
placing a distal end of a second guide wire at a second position within the tubular structure;
passing the guide catheter over the second guide wire; and
removing the second guide wire from the patient while leaving the guide catheter within the patient.
58. A funnel catheter having a distal funnel catheter end, the funnel catheter comprising:
an outer tube;
an inner tube slidably located within the outer tube;
a tubular sleeve having first and second ends and movable between a radially expanded, use state and a radially contracted, deployment state;
the first end of the sleeve being secured to a distal end of the outer tube;
the second end of the sleeve being secured to a distal end of the inner tube; and
the sleeve having a movable, generally U-shaped direction-reversing region so that when the first and second ends move relative to one another the position of the direction-reversing region moves relative to the distal ends of the inner and outer tubes, the direction-reversing region constituting the distal funnel catheter end.
59. The funnel catheter according to claim 58 wherein the tubular sleeve comprises a braided material.
60. The funnel catheter according to claim 59 wherein the tubular sleeve comprises a fluid passage-inhibiting film in contact with the braided material.
61. The funnel catheter according to claim 60 wherein the film impregnates the braided material.
62. The funnel catheter according to claim 60 wherein the film covers the braided material.
63. The funnel catheter according to claim 60 wherein the film is an elastic material.
64. The funnel catheter according to claim 58 wherein the sleeve defines a distally opening funnel when the first and second distal ends are generally aligned.
65. The funnel catheter according to claim 64 wherein the funnel has a generally cylindrical distal portion and a generally conical proximal portion.
66. The funnel catheter according to claim 58 wherein the tubular sleeve is a resilient tubular sleeve and the radially expanded, use state is a relaxed state.
67. A funnel catheter comprising:
an outer tube having a first distal end and an inner surface, the inner surface defining an outer lumen;
an inner tube, slidably located within the outer lumen, having a second distal end and an outer surface positioned opposite the inner surface;
a tubular sleeve having first and second ends and movable between a radially expanded, use state and a radially contracted, deployment state;
the first end of the sleeve being secured to the first distal end;
the second end of the sleeve being secured to the second distal end so to extend from other than the outer surface; and
the sleeve having a movable, generally U-shaped direction-reversing region when the first and second distal ends move relative to one another with the position of the direction-reversing region moving relative to the first and second distal ends.
68. A method for deploying a material-directing element within a tubular structure within a patient comprising:
selecting a funnel catheter having a distal funnel catheter end, the funnel catheter comprising:
an outer tube;
an inner tube slidably located within the outer tube;
a tubular sleeve having first and second ends and movable between a radially expanded, use state and a radially contracted, deployment state;
the first end of the sleeve being secured to a distal end of the outer tube;
the second end of the sleeve being secured to a distal end of the inner tube; and
the sleeve having a movable, generally U-shaped direction-reversing region, the direction-reversing region constituting the distal funnel catheter end;
deploying the funnel catheter with the sleeve in a reduced diameter, deployment state and with the sleeve being generally parallel to the outer and inner tubes;
positioning the direction-reversing region at a chosen position within a tubular structure within a patient; and
moving the distal ends of the inner and outer tubes relative to one another:
causing the position of the direction-reversing region to move relative to the first and second ends;
- causing the sleeve to form a distally-opening material-directing funnel, the funnel having a distal funnel portion and a proximal funnel portion; and
- causing the distal funnel portion to contact the inner wall of the tubular structure.
69. The method according to claim 68 wherein the distal ends moving step causes the sleeve to form a funnel having a generally cylindrical distal portion and a generally conical proximal portion.
70. A method for making a funnel catheter comprising:
winding material onto a mandril to create a tubular braided sleeve having a proximal portion, a distal portion, a proximal end, and a distal end;
removing the tubular braided sleeve from the mandril; and
securing the proximal end to a first position on an outer tube and securing a distal end to a second position on an inner tube to create a funnel catheter.
71. The apparatus according to claim 70 further comprising selecting a mandril comprising a radially expanding proximal taper region connected to a radially contracting distal taper region, the distal taper region having a faster taper than the proximal taper region.
72. The apparatus according to claim 71 wherein the selecting step is carried out to select a mandril have a constant-diameter central region connecting the proximal and distal taper region.
73. The apparatus according to claim 70 wherein the winding step is carried out so that the pic count, that is the material crossing count per unit length, is generally constant along the proximal and distal portions.
74. The apparatus according to claim 70 further comprising aiding the creation of a distally opening funnel when the inner and outer tubes are moved from a first orientation, with the sleeve in a generally tubular state and with the first and second positions separated by a first distance, to a second orientation, with the sleeve in a generally funnel state and with first and second positions separated by a second distance, the second distance being less than the first distance.
75. The apparatus according to claim 74 wherein the aiding step comprises applying a radial expansion restriction material to the proximal portion of the sleeve.
76. The apparatus according to claim 74 wherein the aiding step comprises applying a radial expansion restriction material to the proximal and distal portions of the sleeve, the radial expansion restriction material at the proximal portion being more stretch-resistant than the radial expansion restriction material at the distal portion.
77. The apparatus according to claim 74 wherein the aiding step comprises varying the pic count, that is the material crossing count per unit length, along the sleeve.
78. The apparatus according to claim 77 wherein the pic count varying step comprises creating a lesser pic count at the distal portion of the sleeve than the pic count at the proximal portion of the sleeve.
79. The apparatus according to claim 78 wherein the lesser pic count creating step is carried out by removing selected strands of the winding material at the distal portion of the sleeve.
80. The apparatus according to claim 77 wherein the pic count varying step comprises creating a greater pic count at the distal portion of the sleeve than at the proximal portion of the sleeve.
81. The apparatus according to claim 74 wherein the aiding step comprises the increasing a resistance to radial expansion at the proximal end of the sleeve.
82. The apparatus according to claim 70 wherein the material winding step comprises winding multiple strands of the material onto the mandril.
83. The apparatus according to claim 70 wherein the material winding step comprises winding the material in the form of ribbons of material onto the mandril.
84. A balloon funnel catheter comprising:
a shaft having an end, a main lumen and an inflation lumen;
an annular balloon mounted to the end of the shaft and fluidly coupled to the inflation lumen for movement between a radially contracted, uninflated state and a radially expanded, inflated state;
the balloon defining an open region opening into the main lumen when in the inflated state; and
the balloon extending distally past the end of the shaft when in the inflated state.
85. The catheter according to claim 84 wherein the open region is a funnel shaped open region.
86. The catheter according to claim 84 wherein the main lumen at the end of the shaft has a cross-sectional area and the open region has an average cross-sectional area greater than said cross-sectional area of the main lumen.
87. A method for securing a tubular braid to a tube comprising:
bringing a first end of a tubular braid into engagement with an end portion of a tube, said end portion comprising a temporarily softenable tube material;
softening the temporarily softenable tube material; and
merging the end portion of the tube and the first end of the tubular braid into one another to create a tube material/tubular braid matrix.
88. The method according to claim 87 wherein the bringing step is carried out by inserting a chosen one of the first end and the end portion into the other of the first end and the end portion.
89. The method according to claim 88 wherein the softening step comprises heating the end portion of the tube.
90. The method according to claim 89 wherein the heating step comprises placing the end portion within a tool.
91. The method according to claim 89 wherein the heating step comprises placing the end portion within a heatable tool.
92. The method according to claim 89 wherein the heating step comprises placing the end portion within a tool heatable by RF energy.
93. The method according to claim 89 wherein the heating step comprises placing the end portion within a tool made of a material having a Curie temperature at a desired operational temperature to facilitate maintaining the tool at the desired operational temperature.
94. The method according to claim 90 where the merging step is carried with the end portion and the first end within an open region of the tool.
95. The method according to claim 94 wherein the merging step comprises squeezing the end portion and the first end between the tool and a mandril, the mandril located within the end portion and the first end.
96. A method for controlling the shape of a radially expandable and contractible tubular braid device comprising:
choosing a radially expanded shape for the braid device when the braid device is in a radially expanded state, the radially expanded shape having a length and different cross-sectional dimensions at selected positions along the length;
selectively applying a material to at least some of the selected positions along the braid device; and
adjusting the stretch resistance of the material according to the selected positions;
whereby the different stretch resistances at the selected positions cause the braid device to assume the chosen radially expanded shape when the braid device is in the radially expanded state.
97. The method according to claim 96 wherein the selectively applying step is carried out using a generally elastic material.
98. The method according to claim 96 wherein the selectively applying step is carried out using a generally inelastic material.
99. The method according to claim 96 wherein the selectively applying step is carried out by selectively impregnating the braid device.
100. The method according to claim 96 wherein the choosing step comprises choosing a funnel shape as the radially expanded shape.
101. The method according toclaim 100 wherein the adjusting step comprises decreasing the stretch resistance of the material from a first end towards a second end of the braid device.
102. The method according to claim 96 wherein the selectively applying step applies the material to the braid device along a portion of the length of the braid device.
103. The method according to claim 96 wherein the adjusting step is carried out by changing the thickness of the material according to the desired stretch resistance at the selected positions.
104. The method according to claim 96 wherein the adjusting step comprises selecting an material having different stretch resistance characteristics.
105. The method according to claim 96 wherein the adjusting step comprises selecting different materials having different stretch resistance characteristics.
106. A method for imparting a shape to a thermoplastic membrane comprising:
surrounding at least a portion of a radially expandable device with a thermoplastic membrane;
radially expanding the radially expandable device to a chosen expanded configuration thereby reshaping the thermoplastic membrane to assume an expanded state corresponding to the chosen expanded configuration; and
imparting a set to the thermoplastic membrane while in the expanded state.
107. The method according toclaim 106 wherein the surrounding step is carried out using a generally elastic thermoplastic membrane.
108. The method according toclaim 106 wherein the surrounding step is carried out using a generally inelastic thermoplastic membrane.
109. The method according toclaim 106 further comprising preventing at least a portion of the thermoplastic membrane from adhering to the radially expandable device.
110. The method according toclaim 106 wherein the surrounding step is carried out by sliding a tubular thermoplastic membrane over the radially expandable device.
111. The method according toclaim 106 wherein the surrounding step is carried out by coating the radially expandable device with a thermoplastic liquid material to create the thermoplastic membrane.
112. The method according toclaim 106 further comprising selecting a tubular braid radially expandable device.
113. The method according toclaim 106 wherein the set-imparting step comprises heating and cooling the thermoplastic membrane.
114. The method according toclaim 106 wherein the set-imparting step comprises heating and cooling the thermoplastic membrane a plurality of times.
115. An anastomotic medical device comprising:
a tube having first and second ends and a lumen extending therebetween;
an anchor member at the first end for securing the first end to a first tubular structure of a patient, the first tubular structure having a first open interior, with the first open interior opening into the lumen.
116. The medical device according to claim 115 further comprising a second anchor member at the second end for securing the second end to a second tubular structure of a patient, the second tubular structure having a second open interior, with the second open interior opening into the lumen.
117. The medical device according to claim 115 wherein the anchor member comprises a tubular braid element.
118. The medical device according to claim 115 wherein the anchor member comprises a radially expandable tubular braid element having tubular structure piercing elements.
119. The medical device according toclaim 118 wherein the piercing elements comprise hooks.
120. The medical device according to claim 115 wherein the anchor member comprises an annular inflatable element sealingly engageable with an opening in the first tubular structure.
121. A medical device according to claim 115 wherein the anchor member comprises a malecot device.
122. An anastomotic medical assembly comprising:
a first anastomotic medical device comprising:
a first tube having first and second ends and a first lumen extending therebetween; and
a first anchor member at the first end of the first tube for securing the first end of the first tube to a first tubular structure of a patient, the first tubular structure having a first open interior, with the first open interior opening into the first lumen;
a second anastomotic medical device comprising:
a second tube having first and second ends and a first lumen extending therebetween; and
a second anchor member at the first end of the second tube for securing the first end of the second tube to a second tubular structure of a patient, the second tubular structure having a second open interior, with the second open interior opening into the second lumen; and
the second ends of the first and second tubes connected to one another to create a fluid path between the first and second anchor members, whereby the first and second open interiors of the first and second tubular structures of the patient may be fluidly connected.