US20020022853A1 - Medical anastomosis apparatus - Google Patents

Abstract

A connector for use in providing an anastomotic connection between two tubular body fluid conduits in a patient. The connector is preferably a single, integral, plastically deformable structure that can be cut from a tube. The connector has axial spaced portions that include members that are radially outwardly deflectable from other portions of the connector. The connector is annularly enlargeable so that it can be initially delivered and installed in the patient in a relatively small annular size and then annularly enlarged to provide the completed anastomosis. The radially outwardly deflected members of the first and second portions respectively engage the two body fluid conduits connected at the anastomosis and hold those two conduits together in fluid-tight engagement. Apparatus for use in delivering and deploying a connector is also disclosed.

Description

• This application is a division of U.S. patent application Ser. No. 09/527,668, filed Mar. 17, 2000, which is a division of U.S. patent application Ser. No. 09/186,774, filed Nov. 6, 1998 (now U.S. Pat. No. 6,113,612). Both of these prior applications are hereby incorporated by reference herein in their entireties.[0001]
BACKGROUND OF THE INVENTION
• This invention relates to medical apparatus, and more particularly to apparatus for use in making anastomotic connections between tubular body fluid conduits in a patient.[0002]
• There are many medical procedures in which it is necessary to make an anastomotic connection between two tubular body fluid conduits in a patient. An anastomotic connection (or anastomosis) is a connection which allows body fluid flow between the lumens of the two conduits that are connected, preferably without allowing body fluid to leak out of the conduits at the location of the connection. As just one example of a procedure in which an anastomosis is needed, in order to bypass an obstruction in a patient's coronary artery, a tubular graft supplied with aortic blood may be connected via an anastomosis to the contrary artery downstream from the obstruction. The anastomosis may be between the end of the graft and an aperture in the side wall of the coronary artery (a so-called end-to-side anastomosis), or the anastomosis may be between an aperture in the side wall of the graft and an aperture in the side wall of the coronary artery (a so-called side-to-side anastomosis (e.g., as in published Patent Cooperation Treaty (“PCT”) patent application WO 98/16161, which is hereby incorporated by reference herein in its entirety)). The graft may be natural conduit, artificial conduit, or a combination of natural and artificial conduits. If natural conduit is used, it may be wholly or partly relocated from elsewhere in the patient (e.g., wholly relocated saphenous vein or partly relocated internal mammary artery). Alternatively, no relocation of the graft may be needed (e.g., as in above-mentioned application WO 98/16161 in which a length of vein on the heart becomes a “graft” around an obstruction in an immediately adjacent coronary artery). More than one anastomosis may be needed. For example, a second anastomosis may be needed between an upstream portion of the graft conduit and the aorta or the coronary artery upstream from the obstruction in that artery. Again, this second anastomosis may be either an end-to-side anastomosis or (as shown, for example, in above-mentioned application WO 98/16161) a side-to-side anastomosis. Alternatively, no second, upstream anastomosis may be required at all (e.g., if the graft is an only-partly-relocated internal mammary artery).[0003]
• The currently most common technique for making an anastomosis is to manually suture the two tubular body fluid conduits together around an opening between them. Manual suturing is difficult and time-consuming, and the quality of the anastomosis that results is highly dependent on the skill of the person doing the suturing. In the case of coronary artery bypass procedures, one source of difficulty for suturing of an anastomosis may be motion of the heart. There is also increasing interest in procedures which are less invasive or even minimally invasive. Such procedures have potentially important advantages for patients, but they may increase the difficulty of performing manual suturing of an anastomosis by reducing or limiting access to the site within the patient at which the anastomosis must be made. Various examples of such less invasive or minimally invasive procedures are shown in above-mentioned application WO 98/16161, Goldsteen et al. U.S. Pat. No. 5,976,178, Sullivan et al. U.S. Pat. No. 6,120,432, filed Apr. 23, 1997, Sullivan et al. U.S. patent application Ser. No. 08/869,808, filed Jun. 5, 1997, and Berg et al. U.S. patent application Ser. No. 09/187,364, filed Nov. 6, 1998, all of which are hereby incorporated by reference herein in their entireties.[0004]
• In view of the foregoing, it is an object of this invention to provide apparatus that can be used to make anastomotic connections in lieu of manual suturing.[0005]
• It is another object of the invention to provide apparatus that can be used to make anastomotic connections even though access to the site of the anastomosis may be limited or even only indirect or remote.[0006]
• It is still another object of the invention to provide apparatus that can be used to make anastomotic connections without the need for a high degree of manual suturing skill.[0007]
• It is yet another object of the invention to provide apparatus for making anastomotic connections that is less adversely affected than manual suturing by adjacent or nearby body motion (e.g., motion of the patient's heart).[0008]
• It is still another object of this invention to provide apparatus for facilitating the making of higher quality anastomotic connections more rapidly and with more consistent results than is possible with prior art methods and apparatus such as manual suturing.[0009]
SUMMARY OF THE INVENTION
• These and other objects of the invention are accomplished in accordance with the principles of the invention by providing a connector for use in making an anastomotic connection between two tubular body fluid conduits in a patient, the connector being of substantially one-piece or unitary construction which extends annularly about a central longitudinal axis. The structure of the connector includes axially spaced first and second portions, at least one of which includes members that are deflectable radially out from a remainder of the connector structure. In some embodiments both of the axially spaced first and second portions include members that are deflectable radially out from a remainder of the structure. The connector structure is annularly enlargeable, preferably by inflation of a balloon placed temporarily inside the connector. The structure of the connector preferably lends itself to formation by removal of selected material from a single unitary tube. The connector is typically made of metal which is plastically deformable (e.g., in the above-mentioned radial outward deflections and annular enlargement).[0010]
• The members that are deflectable radially out from the first portion of the connector structure are configured to engage the side wall of one of the two tubular body fluid conduits that are to be connected. The members that are deflectable radially out from the second portion of the connector structure are configured to engage the side wall of the other of the two body fluid conduits that are to be connected. Alternatively, one of the two portions of the connector can be secured (preferably pre-secured) to the associated conduit by other means such as sutures. Annular expansion of the connector preferably causes the first and second portions of the connector structure to move toward one another along the central longitudinal axis of the connector, thereby causing the connector to draw the two tubular body fluid conduits together at the anastomosis between them. This helps produce an anastomosis which is fluid-tight (i.e., from which body fluid does not leak).[0011]
• The connectors of this invention can be used to provide either end-to-side or side-to-side anastomoses. The connector may be first attached to one of the body fluid conduits to be connected (e.g., an end portion of a graft conduit), and then delivered along with the attached end of the first conduit to the connection point with the second conduit, where the connector is fully deployed to produce an anastomosis between the first and second conduits. Prior to full deployment the connector preferably has a relatively small circumference, which facilitates delivery and initial installation in the patient, even at relatively remote or inaccessible locations in the patient. For example, the connector can be delivered via lumens of body fluid conduits in the patient and/or relatively small-diameter instrumentation such as a cannula or laparascopic-type device. Final installation can be performed substantially solely by inflation of a balloon temporarily disposed in the connector. No direct manipulation of the connector may be needed. All of these attributes facilitate use of the connector at remote or inaccessible locations in the patient. The connector therefore lends itself to use in less invasive or minimally invasive procedures.[0012]
• Instrumentation for facilitating installation of the connector through the side wall of a body fluid conduit is also disclosed. This instrumentation has a gradually tapered distal nose portion with an outer surface that is free of features that could snag on the side wall of the body fluid conduit to be penetrated by the nose portion. At least the portion of the connector that must pass through the body fluid conduit side wall is completely covered by the instrumentation until that portion of the connector is through the side wall. These features of the instrumentation help it penetrate the body fluid conduit side wall with no snagging and with minimal trauma. Thereafter the distal nose portion can be shifted distally relative to the connector to expose the connector in position through the side wall. Other parts of the instrumentation (e.g., an inflatable balloon) can then be operated to complete the deployment of the connector.[0013]
• Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments.[0014]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a simplified planar development of the structure of an illustrative embodiment of a connector constructed in accordance with this invention.[0015]
• FIG. 2 is a simplified perspective view of the actual structure of the connector which is shown in planar development in FIG. 1.[0016]
• FIG. 3 is a simplified elevational view of the FIG. 2 structure after some further processing in accordance with the invention.[0017]
• FIG. 4 is a simplified planar development of the structure of FIGS.[0018]1-3 showing that structure's capacity for annular enlargement in accordance with the invention.
• FIG. 5 is a simplified elevational view of the structure of FIG. 3 with some additional structure in accordance with the invention.[0019]
• FIG. 6 is a simplified elevational view, partly in section, of the structure of FIG. 5 with still more additional structure in accordance with the invention.[0020]
• FIG. 7 is a simplified sectional view of the structure of FIG. 6 with additional illustrative apparatus shown for use in delivering and deploying the FIG. 6 structure in a patient in accordance with the invention.[0021]
• FIG. 8 is a simplified elevational view, partly in section, showing an early stage in use of the FIG. 7 apparatus in accordance with the invention.[0022]
• FIG. 9 is a view similar to FIG. 8, but with more elements shown in section, and showing a later stage in use of the FIG. 7 apparatus in accordance with the invention.[0023]
• FIG. 10 is a view similar to FIG. 9 showing a still later stage in use of the FIG. 7 apparatus in accordance with the invention.[0024]
• FIG. 11 is a view similar to FIG. 10 showing the end result of using the FIG. 7 apparatus in accordance with the invention.[0025]
• FIG. 12 is a view similar to FIG. 1 for another illustrative embodiment of a connector constructed in accordance with the invention.[0026]
• FIG. 13 is a view similar to FIG. 4, but for the embodiment of FIG. 12.[0027]
• FIG. 14 is a simplified perspective view showing the connector of FIG. 12 with other elements in accordance with the invention.[0028]
• FIG. 15 is another simplified perspective of a later stage in use of some of the elements shown in FIG. 14.[0029]
• FIG. 16 is another simplified perspective view, partly in section, of a still later stage in use of the elements shown in FIG. 15.[0030]
• FIG. 17 is another view, generally similar to FIG. 16, showing an even later stage in use of the elements shown in FIG. 16.[0031]
• FIG. 18 is a simplified perspective view of a completed anastomosis including the connector of FIG. 12.[0032]
• FIG. 19 is another view, partly in section, of the anastomosis of FIG. 18.[0033]
• FIG. 20 is a simplified perspective view of an illustrative embodiment of a starting structure for use in making connectors in accordance with the invention.[0034]
• FIG. 21 is a simplified elevational view, partly in section, illustrating a possible modification of connectors in accordance with the invention.[0035]
• FIG. 22 is a simplified elevational view, partly in section, illustrating another possible modification of connectors in accordance with the invention.[0036]
• FIG. 23 is a simplified sectional view of an alternative finished anastomosis in accordance with the invention.[0037]
• FIG. 24 is a view similar to FIG. 4 for still another illustrative embodiment of a connector constructed in accordance with the invention.[0038]
• FIG. 25 is a view similar to FIG. 11 for a completed anastomosis employing a connector of the type shown in FIG. 24.[0039]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• FIG. 1 shows a planar development of what is actually an integral, one-piece (unitary),[0040]annular structure10. In particular, the left and right edges of the structure shown in FIG. 1 are actually joined to and integral with one another. Thus the actual structure is as shown in FIG. 2, although FIG. 1 is useful to more clearly reveal the details of various features of the structure. A central longitudinal axis12 about whichstructure10 is annular is shown in FIG. 2.
• An illustrative material for[0041]structure10 is 304 stainless steel. Other examples of suitable materials include tantalum, tungsten, platinum, and nitinol.Structure10 may be advantageously produced by starting with a single, unitary metal tube and removing selected material until only the structure shown in FIG. 2 remains. For example, laser cutting may be used to remove material from the starting tube in order to producestructure10. Althoughconnectors10 can be made in various sizes for various uses, a typical connector has an initial outside diameter in the range from about 0.040 to about 0.065 inches, an initial length of about 4.0 mm, and a material thickness of about 0.004 inches.
• [0042]Connector10 may be described as including axially spaced first andsecond portions20 and40, respectively.First portion20 includes a plurality of annularly spacedmembers22 that in this case havefree end portions24 that are sharply pointed and that point towardsecond portion40. Each ofmembers22 is deflectable radially out from the remainder ofstructure10 as shown, for example, in FIG. 3. This outward deflection is preferably at least partly plastic.
• [0043]Second portion40 also includes a plurality of annularly spacedmembers42 that in this case havefree end portions44 that are sharply pointed and that point towardfirst portion20. Each ofmembers42 is deflectable radially out from the remainder ofstructure10 as shown, for example, in FIG. 3. Again, this outward deflection is preferably at least partly plastic.
• The above-mentioned outward deflection of[0044]elements22 and42 can be produced by putting the connector on a mandrel and pryingelements22 and42 radially outward.
• [0045]Connector10 is formed in such a way that it is annularly enlargeable (e.g., by inflation of a balloon that is temporarily disposed inside the connector). The annularly expanded condition ofconnector10 is shown in FIGS. 4, 10, and11. The annular expandability ofconnector10 is provided by making the connector with a plurality of annularly adjacent, annularly enlargeable cells. For example, a typical cell includes annularly spaced, but adjacent,longitudinal members50aand52a. The axially spaced ends of this pair of members are connected to one another at54aand56a. The next annularly adjacent similar cell includeselements50b,52b,54b, and56b. Annularly adjacent ones of these cells are connected to one another (e.g., as at66a) at locations which are axially medial to their axial end connections54 and56. In thisway structure10 is annularly enlargeable by annularly enlarging each of the above-mentioned cells (see FIG. 4).
• In addition to the cells that are described above,[0046]structure10 includes other, similarly annularly expandable cells that are axially and annularly offset from the first-described cells. A representative one of these other cells includes annularly adjacentlongitudinal members60aand62a, the axially spaced ends of which are connected at64aand66a. (It should be noted that part of member60ais common with part ofmember52a, and part ofmember62ais common with part ofmember50b.) The next annularly adjacent cell of this kind includescomponents60b,62b,64b, and66b. Annularly adjacent cells of this kind are connected to one another at locations like54b, which are axially medial the axial endpoints64 and66 of those cells. Thus again the structure is annularly enlargeable by annularly enlarging these cells as shown, for example in FIG. 4.
• It will be appreciated that as[0047]structure10 annularly enlarges, it generally axially shortens. In other words, as cells50/52/54/56 and60/62/64/66 widen in the annular direction, they shorten in the axial direction. Thus annular enlargement ofstructure10 decreases the axial spacing betweenportions20 and40, and more particularly decreases the axial spacing betweenmember22, on the one hand, andmembers42, on the other hand.
• A typical use of[0048]connector10 is, in a coronary artery bypass procedure, to provide an anastomosis between an axial end portion of a tubular graft conduit and an aperture in a side wall of a coronary artery. For this kind ofuse connector10 may be loaded on anuninflated balloon110 near the distal end of aballoon catheter100 as shown in FIG. 5. In other words,connector10 andcatheter100 are assembled so thatconnector10 extends annularly arounduninflated balloon110.
• [0049]Graft conduit120 is then placed annularly around thefirst portion20 ofconnector10 and the adjacent portion ofcatheter100 as shown in FIG. 6. Graft conduit may be natural body tissue (e.g., a length of the patient's saphenous vein harvested for use as a graft, a partly severed internal mammary artery, etc.), an artificial graft (e.g., as shown in Goldsteen et al. U.S. Pat. No. 5,976,178, or published PCT patent application WO 98/19632, both of which are hereby incorporated by reference herein in their entireties), or a combination of natural and artificial conduits (e.g., a length of natural conduit disposed substantially concentrically inside a length of artificial conduit).Graft conduit120 is placed onassembly 10/100 so that radially outwardly deflectedmembers22 penetrate and pass through the side wall of the graft conduit (e.g., as a result of compressing the graft against the fingers, thereby forcing the fingers to pierce through the graft wall). The sharpened free ends ofmembers22 facilitate penetration ofconduit120 bymembers22. The blunt rear surfaces of enlargedfree end portions24 resist withdrawal ofmembers22 fromconduit120 aftermembers22 have penetrated the conduit. The graft may be additionally or alternatively directly sutured to the connector body. If the alternative of suturinggraft120 to the connector is used, then thefirst portion20 of the connector may not need radially outwardlydeflectable members22 for engagement of the graft conduit.
• As an alternative to securing[0050]graft120 toconnector10 afterballoon110 has been associated with the connector,balloon110 may be installed inconnector10 after the graft has been secured to the connector.
• [0051]Illustrative apparatus200 for deliveringconnector10 andgraft120 to a location in a patient requiring a graft and an anastomosis, and for then deploying the connector and graft, is shown in FIG. 7.Apparatus200 includes anoptional guide wire210, which may be first installed in the patient along the route that the remainder of the apparatus is later to follow to reach the desired location in the patient. The remainder of the apparatus is then slid into the patient alongguide wire210. Alternatively,guide wire210 may be omitted, or a leading guide member (e.g., a wire) may be fixedly mounted on the distal (leftward in FIG. 2) end of the remainder of the apparatus. The wire allows precise tracking of thenose cone220 anddelivery system200 into a patient's body fluid conduit (e.g., acoronary artery300 as shown in FIGS.8-10 and described below).
• [0052]Apparatus200 includes a gradually tapered distal nose portion ordilator220 which extends annularly around a central, longitudinally extending,guide wire lumen222.Distal nose portion220 has a substantially conical outer surface with a cone angle A, which is preferably less than about 15° (e.g., in the range from about 5° to about 15°, more preferably in the range from about 5° to about 10°). Such gradual tapering ofnose portion220 is desirable to enable nose portion to gradually enlarge an aperture in a side wall of a body fluid conduit to whichgraft120 is to be connected without snagging on that conduit side wall. This geometry allows optimal passage across a body conduit wall (e.g., a coronary artery wall as shown in FIG. 8 and described below) with minimal wall damage, with minimal force being required, and with no catching or snagging on the wall.Distal nose portion220 may have cutting edges to further facilitate entry through a body fluid conduit side wall.
• [0053]Distal nose portion220 is connected totube230, which extends proximally from the nose portion annularly aroundguide wire210. Thus the lumen oftube230 constitutes a proximal continuation ofguide wire lumen222.Tube230 may be made of stainless steel hypotube, which allows the depicted apparatus to be pushed or pulled axially alongguide wire210.
• A proximal portion of[0054]distal nose portion220 is hollowed out as indicated at224 to receiveballoon110,connector10, and a distal portion ofgraft120 substantially coaxially around a medial portion oftube230. For thisarrangement balloon110 is provided as a hollow annulus at or near the distal end of hollowtubular member100. The side wall oftube100 may include a separate lumen (not shown but conventional for balloon catheters) through which pressurized inflation fluid may be supplied from a proximal region of the apparatus to balloon110.Elements100 and110 are slidable axially along the outer surface oftube230. Insertion ofelements10,110, and120 (FIG. 6) into theannular recess224 indistal nose portion220 deflects the radially outermost portions ofmembers22 back overgraft120 as shown in FIG. 7.Tube240, disposed substantially coaxially aroundelement100 insidegraft120 so that its distal end bears againstmembers22, may be used to help loadelements10,110, and120 intorecess224, and also to holdconnector10 in place inrecess224 during delivery of the connector to the anastomosis site in the patient.
• FIG. 8 shows a typical use of[0055]apparatus200 to delivergraft120 for connection to an aperture in a side wall of a patient's tubular body conduit300 (e.g., a coronary artery requiring a bypass graft).Guide wire210 is first installed through a small aperture in the side wall of the conduit. The natural elastic recoil of theconduit300 side wall seals the aperture around the guide wire so that there is little or no body fluid (e.g., blood) leakage out of the conduit via the aperture. The tapereddistal nose portion220 ofapparatus200 is then gradually forced into the aperture (e.g., by usingtube230 to pushportion220 distally into the aperture) to dilate the aperture. The natural elastic recoil of theconduit300 side wall tissue continues to keep the aperture sealed or substantially sealed aroundportion220.
• When[0056]distal nose portion220 has been pushed far enough into the aperture in the side wall ofconduit300 so thatconnector10 is part way through the aperture, further distal motion ofelements10,100,110, and120 can be stopped (e.g., by holding a proximal portion ofelement100 stationary).Tube240 is then pulled proximally out of the patient. Thereafter,distal nose portion220 is pushed farther into conduit300 (e.g., by continuing to push distally on a proximal portion of element230). This causesdistal nose portion220 to separate fromconnector10, thereby exposing the connector and leaving it in the aperture through theconduit300 side wall as shown in FIG. 9.
• The next step in use of[0057]apparatus200 is to inflateballoon110 as shown in FIG. 10. The balloon is typically sized to a specific anastomosis size (e.g., 3 millimeters diameter, 4 millimeters diameter, etc.). Inflation of theballoon forces connector10 to annularly enlarge by enlarging cells50/52/54/56 and60/62/64/66 in the annular direction. In addition, the portions of members60 and62 that are adjacent to elements64 (as well as elements64 and42) are deflected radially out beyond other portions of the connector inside the side wall ofconduit300, thereby causing the extreme distal end ofgraft120 to similarly flare out inside that side wall. This outward flaring of portions ofconnector10 andgraft120 helps secure the connector and graft to the side wall ofconduit300, and also helps seal the graft to the conduit. The axial shortening ofconnector10 that accompanies annular enlargement ensures thatgraft120 is drawn into secure and fluid-tight engagement withconduit300. The free ends ofmembers42 preferably penetrate the side wall ofconduit300 to furthersecure connector10 andgraft120 in the aperture in the side wall.Members50,52,56, and24 may also flare out somewhat outside the side wall ofgraft300 to help ensure thatgraft120 remains open where it connects toconduit300. Assuming that the connector is approximately properly positioned relative to the side wall ofconduit300 prior to inflation ofballoon110, the connector is effectively self-centering on theconduit300 side wall as the balloon is inflated.
• The next step in use of[0058]apparatus200 is to deflateballoon110 and withdraw all ofelements100,110,210,220, and230 (e.g., by pulling them proximally out of graft120). This leaves the axial end portion ofgraft120 connected to the side wall ofconduit300 by annularlyenlarged connector10 as shown in FIG. 11. In particular, in thisexample connector10 provides an end-to-side anastomosis betweengraft120 andconduit300. Body fluid fromgraft120 is able to flow intoconduit300 via this connection.Connector10 pressesgraft120 radially outward against the aperture through the side wall ofconduit300 all the way around that aperture, thereby preventing body fluid from leaking out ofconduits120 and300.Connector10 also prevents the end ofconduit120 from pulling out of the side wall ofconduit300.
• Another illustrative embodiment of a[0059]connector410 in accordance with this invention is shown (in simplified planar development) in FIG. 12. Again, althoughconnector410 can be made in various sizes for various uses, a typical initial length ofconnector410 is about 4.0 mm, and a typical initial outside diameter is in the range from about 0.040 to about 0.065 inches. A typical shaft length formembers422 is about 0.0539 inches, and a typical shaft width for those members is about 0.0050 inches. As in the case ofconnector10,connector410 may be cut from a single integral tube. A typical thickness for the material ofconnector410 is about 0.004 inches. Suitable materials forconnector410 include stainless steel, tantalum, tungsten, platinum, and nitinol.
• [0060]Connector410 may be described as including axially spaced first andsecond portions420 and440, respectively.First portion420 includes a plurality of annularly spacedfirst members422 havingfree end portions424 that initially point axially away fromsecond portion440. However,members422 are deflectable radially out from other parts of the connector, and, if desired,free end portions424 can be curved back so that they point toward second portion440 (see FIG. 15).
• The[0061]first portion420 ofconnector410 may also be said to include the lower portions (below members454) of cells, each of which includes onemember460, onemember462, onemember464, and onemember466. For example, the left-most cell shown in FIG. 12 includes substantiallyparallel members460aand462ajoined at their axially spaced ends by members464aand466a. Annularly adjacent cells are joined by members454 at points that are axially medial their axial ends. For example, the cell that includesmember462ais joined to the cell that includesmember460bbymembers454b. The portions ofmembers460 and462 below members454 are also deflectable radially out from other portions of the connector.
• The[0062]second portion440 ofconnector410 may be said to include the portions ofmembers460 and462 above members454. These portions ofmembers460 and462 are also deflectable radially out (asloops460/462/464) from other portions of the connector. If desired,loops460/462/464 could also have fingers or barbs on them likemembers42 in the embodiment of FIGS.1-11.
• [0063]Connector410 is annularly enlargeable by deformingmembers460 and462 to enlarge each of the above-described cells in the annular direction as shown in greatly simplified form in FIG. 13.
• FIG. 14 shows an illustrative embodiment of[0064]tooling500 that can be used to facilitate attachment of agraft conduit120 toconnector410. Tooling500 includes a mandrel with a conical end portion, the pointed free end of which is small enough to fit axially intoconnector410 in its initial relatively small annular size. Asconnector410 is forced farther onto the conical end portion ofmandrel500, the cone of the mandrel begins to deflectmembers422 radially out from other portions of the connector.Graft conduit120 can be placed aroundmandrel500 and shifted axially towardconnector410 until an axial end portion ofconduit120 axially overlaps outwardly deflectedmembers422. The free end portions ofmembers422 can then be pried out through the side wall ofconduit120 as shown in FIG. 15 to secureconnector410 toconduit120.Mandrel500 can be pulled proximally out ofgraft120 andconnector410 at any suitable time. Use ofmandrel500 in this way helps ensure thatmembers422 penetrate the side wall ofconduit120 substantially equidistantly in the annular direction around the conduit. This helps avoid excessive stretching of any angular segment ofgraft120 whenconnector410 is subsequently expanded byballoon110.
• After[0065]connector410 has been attached to graft120 as shown in FIG. 15, an inflatable balloon like balloon110 (with tube100) can be inserted into the connector in a manner similar to what is shown in FIG. 6.Elements100,110,120, and410 can then be loaded into apparatus like200 in a manner similar to what is shown in FIG. 7 (except that in this case the free ends424 ofmembers422 will typically point in the distal direction rather than in the proximal direction as is true for the free ends24 ofmembers22 in FIG. 7).Apparatus200 can then be used to installconnector410 andgraft120 in a patient in a manner similar to the installation shown in FIGS.8-11. FIG. 16 shows thesecond portion440 after it has been conveyed through the side wall ofconduit300 byapparatus200 andapparatus200 has been shifted distally farther intoconduit300 to expose the connector. FIG. 17 showssecond portion loops460/462/464 deployed (radially outwardly deflected), but the remainder of the connector not yet annularly expanded. A shaped balloon or dual balloon system may be utilized to achieve this. For example, one of two axially adjacent balloons may be used to help formdistal retention fingers460/462/464 as shown in FIG. 17. The second of the two balloons is thereafter used to annularly expand the remainder of the connector and the anastomosis opening. Alternatively, a single “bulbous” shaped balloon may be used to produce a temporary intermediate condition like that shown in FIG. 17, and to then annularly enlarge the remainder of the connector and the anastomosis opening. As still another possibility thedistal retention fingers460/462/464 may be self-actuating (i.e., spring-biased) and not require balloon assist to spring out to the condition shown in FIG. 17. For example,distal retention fingers460/462/464 may be preformed to deflect radially outward in a manner similar to the radially outward preform that is given toelements22 and42 in FIG. 3.
• The final[0066]anastomosis employing connector410 is shown in FIGS. 18 and 19. In particular, as shown in FIGS. 18 and 19connector410 has been annularly expanded by enlargement of thecells460/462/464/466 in the annular direction. The portions ofmembers460 and462 that compriseportion440 of the connector have been deflected radially out from other portions of the connector insideconduit300, thereby functioning to secureconnector410 andgraft120 toconduit300.Members422 are deflected radially out from other portions of the connector and pass through the axial end portion ofgraft120. The free end portions ofmembers422 point toward thesecond portion440 of the connector, thereby ensuring that the end ofgraft120 cannot slip away from its body-fluid-sealing abutment with the side wall ofconduit300. The annularly expanded medial portion ofconnector410 holds open the aperture in the side wall ofconduit300, as well as the attached end ofgraft120, thereby ensuring unobstructed body fluid flow through the anastomosis betweenconduits120 and300.
• Still another illustrative embodiment of a[0067]connector610 in accordance with this invention is shown in greatly simplified, annularly expanded, planar development in FIG. 24.Connector610 is configured for use in performing a side-to-side anastomosis between twobody fluid conduits300aand300bas shown in FIG. 25.Connector610 has a construction like twoportions40 ofconnector10 connected together. Thusmembers642aand642bare constructed and operate likemembers42 inconnector10. Similarly,members660 are constructed and operate generally like members60 and62 inconnector10, andelements664 and666 are constructed and operate generally like elements64 and66, respectively, inconnector10.
• [0068]Connector610, in an initially relatively small annular size and mounted on a balloon, is insertable through adjacent apertures in the side walls ofbody fluid conduits300aand300b. For example, apparatus like200 can be used to deliverconnector610 to such a site via the lumen of one ofconduits300 and to then position the connector so that it spans both conduits.Apparatus200 is then shifted relative toconnector610 in a manner generally similar to FIG. 9 to expose the connector. Theballoon110 associated with the connector is then inflated to annularly enlarge the connector to the condition shown in FIG. 25. In particular, this annular expansion causesmembers642ato penetrate the side wall ofconduit300aannularly around the anastomotic opening, and also causesmembers642bto penetrate the side wall of conduit300bannularly around the anastomotic opening. As with the other connectors of this invention, annular enlargement ofconnector610 is accompanied by axial shortening, which helps to draw the side walls ofconduits300aand300btogether annularly around the connector, thereby providing the desired fluid-tight anastomosis between the conduits. When the anastomosis is thus complete, the balloon inside the connector is deflated and all the apparatus is withdrawn through the anastomosis.
• It will be understood that the foregoing is only illustrative of the principles of this invention, and that various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. For example, the number and shape of the annularly enlargeable connector cells can be different from what is shown in the drawings herein. The number of axially adjacent rows of annularly enlargeable cells can be different from the numbers of such rows that are shown herein (i.e., two rows of cells in the case of[0069]connectors10 and610 or one row of cells in the case of connector410). For example, a connector may have three, four, or more rows of cells. The cells may have any of many forms, depending on the desired degree of expansion and final radial strength. The number of cells, the number of rows of cells, the size of the cells, and the geometry of the cells can all be selected to control the expansion, strength, and sizing of the finished connector. The number and shape of the radially outwardly deflectable connector members can also differ from what is shown herein. Techniques and apparatus different from what is shown and described herein can be used for attaching a connector of this invention to a graft conduit and/or installing the connector in a patient. Instead of the extreme end ofgraft120 being insideconduit300, the connector of this invention may be configured to secure the end of thegraft120 against the outside of the side wall ofconduit300 in an end-to-side anastomosis as shown in FIG. 23. Thenose cone220 ofapparatus200 may not need to cover theproximal fingers22 or422 of the connector. Instead, the proximal fingers can extend to an outer circumference which is larger than the outer circumference ofnose cone220. This allows the proximal fingers to be used as a stop which prevents the connector from going too far through the aperture in the side wall ofconduit300. In other words, the radially outer ends ofproximal fingers22 or422 come into contact with the outer surface of the side wall ofconduit300 and thereby stop the connector from going any farther into that conduit.
• Although considerable variation in the connectors of this invention is thus possible and contemplated, in general such connectors comprise a unitary structure disposed annularly about a longitudinal axis (e.g., axis[0070]12 in FIG. 2). The connector structure generally has axially spaced first and second portions (e.g.,20 and40,420 and440, or640aand640bin the depicted illustrative embodiments). The first portion generally has a plurality of annularly spaced first members that are deflectable radially out from a remainder or other generally axially medial portion of the structure. For example, in the illustrative embodiment shown in FIGS.1-11 these first members includeelements22. In the illustrative embodiment shown in FIGS.12-19 these first members includeelements422. In the illustrative embodiment shown in FIGS. 24 and 25 these first members includeelements642a. The second portion may also have a plurality of annularly spaced second members that are deflectable radially out from a remainder or other generally axially medial portion of the structure. For example, in the illustrative embodiment shown in FIGS.1-11 these second members includeelements44 and (later in use of the connector) the portions of elements60 and62 that are above elements54 in FIG. 1. In the illustrative embodiment shown in FIGS.12-19 the second members include U-shaped structures that are the portions ofelements460,462, and464 above elements454 in FIG. 12. In the illustrative embodiment shown in FIGS. 24 and 25 these second members includemembers642b. Also, in general, the connector structures of this invention are annularly enlargeable. For example, in the illustrative embodiment shown in FIGS.1-11 the connector is annularly enlargeable by enlarging cells50/52/54/56 and60/62/64/66 in the annular direction as shown, e.g., in FIG. 4. Similarly, in the illustrative embodiment shown in FIGS.12-19 the connector is annularly enlargeable by enlargingcells460/462/464/466 in the annular direction as shown, e.g., in FIG. 13. And in the embodiment shown in FIGS. 24 and 25 the connector is annularly enlargeable by enlargingcells660/664/666 in the annular direction.
• It will be appreciated that, in general, the structure of the connectors of this invention is such that radial enlargement of the connector reduces the axial spacing between the above-mentioned first and second members. This helps the connector draw together in a fluid-tight way the two body fluid conduits that are to be connected by the connector. In the embodiment shown in FIGS.[0071]1-11, for example, annular enlargement of cells60/62/64/66 causes a decrease in the axial spacing betweenmembers22, on the one hand, andmembers42, on the other hand. Similarly, in the embodiment shown in FIGS.12-19 annular enlargement ofcells460/462/464/466 causes a decrease in the axial spacing betweenmembers422, on the one hand, and the portions ofelements460 and462 above elements454 in FIG. 12, on the other hand. And in the embodiment shown in FIGS. 24 and 25 annular enlargement of the connector decreases the axial spacing betweenmembers642a, on the one hand, andmembers642b, on the other hand. The above-described axial shortening of the connector advantageously applies compressive forces (for sealing) to the body fluid conduits being connected.
• In general, most of the deformation of the connectors of this invention is preferably plastic strain and therefore permanent. The deformation thus referred to includes both the above-described radially outward deflection of members like[0072]22,42,422,642, etc., and the above-described radial enlargement of the connector.
• The radially outwardly deflectable members or portions of the connector may be barbs, hooks, spikes, loops, or suture rings.[0073]
• The connectors of this invention may be constructed so that different portions of the connector annularly enlarge in response to different amounts of applied annular enlargement force. For example, in the embodiment shown in FIGS.[0074]1-11, the portions of the structure above elements54 in FIG. 1 may be made so that they are less resistant to inflation of aballoon110 inside the connector than portions of the structure below elements54 in FIG. 1. In an application of the type shown in FIGS.1-11 this causes these less resistant portions to annularly enlarge by deflecting radially out insideconduit300 before the remainder of the connector begins to significantly annularly enlarge. This early response of the less resistant portions insideconduit300 may help to ensure that the connector does not slip out of engagement withconduit300 during annular enlargement of the connector. This technique of making different portions of the connector with different strengths can be used to provide any sequence or phasing of annular enlargement of various portions of the connector. Alternatively or additionally, the connector can be shaped, molded, or phased in any desired way by providing aballoon structure110 which is shaped, molded, or phased in that way. For example,balloon structure110 may comprise two or more separately inflatable balloons of the same or different inflated circumferential size. Two such balloons may be axially displaced from one another inside the connector so that axially different portions of the connector can be annularly enlarged at different times and/or by different amounts.
• Radiologically (e.g., x-ray) viewable markers can be used anywhere on the connectors and/or delivery apparatus (e.g.,[0075]200) of this invention to facilitate radiologic observation of the proper placement and deployment of a connector in a patient if the connector-utilizing procedure is such that more direct visual observation is not possible or sufficient. One way to enhance the radiologic viewability of connectors in accordance with this invention is to make them from clad tubing. Clad tubing has two (or more) substantially concentric layers of metal, each with a desired property. As shown in FIG. 20, for example,clad tubing500 has atantalum layer502 over astainless steel layer504. Thetantalum layer502 provides radiodensity, thereby making aconnector10,410, or610 that is cut fromtube500 radiologically viewable. Thestainless steel layer504 provides rigidity to the connector. The medial section can be ground to reduce the thickness ratio to favor the tantalum. This improves the ability for balloon expansion. Although tube500 (and the resultingconnector10,410, or610) may thus be made of two or more layers of different materials, the tube and the connector are still accurately described as unitary, one-piece, or integral. As an alternative to using clad tubing, the connector may be plated with a radiologic material to give it a desired radiodensity. Another example of a material suitable forradiologic layer502 is platinum.
• Small polyester or other polymer patches or bands may be used on or in association with a connector of this invention to help seal and coagulate blood. Such patches may be inserted over individual fingers as shown, for example, at[0076]522 in FIG. 21. Alternatively, such a band or web may be provided around the medial portion ofconnector10,410, or610 as shown, for example, at530 in FIG. 22. A band or web like530 may also be used to constrain the size of the connector or a graft (such as a vein graft) relative to the connector. Vein grafts may dilate significantly under arterial blood pressure. A band or web can be used to fix its size relative to the connector. Alternatively or additionally a band or web like530 can be provided to help seal the completed anastomosis. For purposes of these various kinds, a band or web like530 may preferably be elastic (e.g., of a rubber or rubber-like material such as silicone or polyurethane). The band or web like530 can be porous, if desired, and may be impregnated with drugs to facilitate healing and/or sealing. Similarly, polymer patches like522 in FIG. 21 can include and release coagulant and/or other medication to help prevent bleeding and promote healing. Patches like522 in FIG. 21 can help prevent members like22 from pulling back through tissue that the member has penetrated.
• An important attribute of the connectors of this invention is the characteristic that the medial section is soft enough to allow balloon expansion and strong enough to secure the two body fluid conduits via such elements as[0077]22 and42,422 and460/462/464, or642. To achieve this with a single material and wall thickness, which may be preferable from a manufacturing perspective, the center section may be annealed selectively to soften it without compromising the rigidity of the retention elements (e.g.,22,42,422,642, etc.). This can be done, for example, by laser heat treating the medial section only. The results of this process are relatively low hardness in the medial section and relatively high hardness in the end sections, all within an overall length of about 0.2 inches.
• The connectors of this invention may also be made of a super-elastic material such as nickel-titanium (“nitinol”), which would allow a similar geometry as stainless steel to self-deploy or actuate in-vivo.[0078]
• It will be appreciated that the fact that the connectors of this invention can be initially relatively small in circumference, and that they can be remotely controlled to position them in the patient and to then annularly expand them for final deployment, facilitates use of these connectors and associated apparatus (e.g., apparatus[0079]200) at remote and/or inaccessible locations in a patient. For example, a connector of this invention may be delivered into and installed in a patient (using apparatus such as apparatus200) through relatively small instrumentation such as laparascopic apparatus, a cannula, or an intraluminal catheter. Thus a connector and associated apparatus (e.g., apparatus200) of this invention can be used in any of the procedures mentioned earlier in this specification, and in particular in procedures and with other elements shown in any of above-mentioned references WO 98/16161, U.S. Pat. Nos. 5,976,178, 6,120,432, U.S. Ser. Nos. 08/869,808, and 09/187,364. Alternatively, the connector and/or apparatus (e.g., apparatus200) of this invention can be used in more traditional or conventional surgical procedures or in other, known, less invasive or minimally invasive procedures. As just some examples of possible uses of the connectors and apparatus of this invention, they can be used to perform an anastomosis to a beating or still heart without the use of sutures or direct access.
• Again, although the connectors of this invention can be made in various sizes for various uses, a typical connector is initially less than about 1 millimeter in diameter and in the range from about 2 to about 4 millimeters in length. After annular enlargement, a typical connector is more than about 2.5 millimeters in diameter. The pre-yield geometry of these connectors is ideal for delivery and positioning; the post-yield geometry is ideal for vessel securement, seal, and patency. The geometry of the connectors is ideal for annular enlargement. Radial outward deflection of certain connector members such as[0080]22,42,422,642, etc., is ideal for interfacing the expanding medial section of the connector to each of the two body fluid conduits to be connected (e.g., a graft vessel and an artery vessel).
• As has been explained, certain connector cells may be configured to open before other cells as desired to optimize deployment positioning. Integral connector fingers such as[0081]22,42,422,642, etc., can be deflected radially out from the remainder of a connector for the purpose of attachment to body fluid conduits (e.g., a graft and an artery). These fingers are part of the connector body and can be hooks, barbs, loops, or spikes. The geometry of the fingers can also change, as desired, in response to balloon expansion. A balloon catheter can be used to actuate the connector and provide an anastomosis opening and attachment. Thenose cone portion220 ofapparatus200 covers the connector and graft interface, allowing dilation of the other body fluid conduit wall and passage of the connector through that wall. The connector provides the actual anastomotic opening and the connection simultaneously. The device is actuated via a balloon and catheter delivery system.
• Among the advantages of the invention are that it eliminates suturing and reduces the time required to produce an anastomosis. In major circulatory system repair procedures such as cardiac bypass procedures, this can reduce cardiopulmonary pump time, which is of great benefit to the patient. The invention provides optimal flow dynamics, e.g., from a graft to the coronary artery. The blood entrance angle can be engineered into the connector geometry rather than relying on suture skill or technique. The invention eliminates possible suture injury to vessels. At the high stress site of an anastomosis sutures are eliminated. The connector and a graft can be delivered percutaneously, e.g., as in several of the references that are mentioned above. Direct access required for suturing is eliminated. An anastomotic connection can be made to a beating heart.[0082]

Claims (24)

The invention claimed is:

1. Apparatus for inserting an annular anastomotic connector into a side wall of a tubular body tissue conduit comprising:

a substantially conical tip structure having a cone angle less than about 15° and configured for passage through the side wall starting with an apex of the cone; and

a shaft structure extending from the tip structure in a direction away from the apex and configured to receive the connector annularly around the shaft structure.

2. The apparatus defined inclaim 1 wherein the cone angle is in the range from about 5° to less than about 15°.

3. The apparatus defined inclaim 1 wherein the cone angle is in the range from about 5° to about 10°.

4. The apparatus defined inclaim 1 wherein the tip structure is configured to receive and annularly surround at least a portion of the connector.

5. The apparatus defined inclaim 1 wherein an axial portion of the connector is configured to extend through the side wall of the conduit, and wherein the tip structure is configured to axially receive and annularly surround said axial portion of the connector.

6. The apparatus defined inclaim 1 further comprising:

a longitudinal guide structure extending axially from the apex in a direction away from the connector, the guide structure being configured to extend through an aperture in the side wall and then axially along a lumen inside the conduit.

7. The apparatus defined inclaim 6 wherein the guide structure is axially fixed to the tip structure.

8. The apparatus defined inclaim 6 wherein the tip structure and the shaft structure are axially reciprocable along the guide structure.

9. The apparatus defined inclaim 8 wherein the guide structure extends axially along a lumen through the tip structure and the shaft structure.

10. The apparatus defined inclaim 1 wherein the shaft structure is configured to extend axially from the tip structure farther than the connector, and wherein the shaft structure is connected to the tip structure so that the shaft structure can be used to push the tip structure in the direction of the apex.

11. The apparatus defined inclaim 1 further comprising:

a radially expandable structure configured for disposition annularly around the shaft structure and inside the connector around the shaft structure.

12. The apparatus defined inclaim 11 further comprising:

a tubular member configured for disposition around the shaft structure, the radially expandable structure being secured to the tubular member.

13. The apparatus defined inclaim 12 wherein the tubular member and the radially expandable structure are reciprocable axially along the shaft structure.

14. The apparatus defined inclaim 11 wherein the radially expandable structure comprises:

an inflatable annular balloon.

15. The apparatus defined inclaim 4 further comprising:

a tubular member configured for disposition around the shaft structure and further configured for use in keeping the connector received by the tip structure.

16. The apparatus defined inclaim 15 wherein the tubular member is further configured for reciprocation axially along the shaft structure.

17. The method of producing a hollow annular anastomotic connection between a first aperture in a side wall of a body tissue conduit in a patient and a second aperture in a side wall of a graft conduit relocated from elsewhere in the patient's body comprising:

introducing a hollow annular connector into the graft conduit so that a first axial portion of the connector is disposed inside the graft conduit and a second axial portion of the connector extends out of the graft conduit via the second aperture and into the body tissue conduit via the first aperture; and

deforming the connector so that it presses together the side walls of the body tissue conduit and the graft conduit annularly around the first and second apertures.

18. The method defined inclaim 17 further comprising:

shielding the second axial portion of the connector during at least part of the introducing.

19. The method defined inclaim 18 further comprising:

unshielding the second axial portion of the connector after the shielding but prior to the deforming.

20. The method defined inclaim 17 wherein the deforming comprises:

annularly enlarging the connector.

21. The method defined inclaim 17 wherein the deforming comprises:

axially shortening the connector.

22. The method defined inclaim 17 wherein the connector is disposed annularly around a selectively inflatable balloon, and wherein the deforming comprises:

inflating the balloon.

23. The method defined inclaim 22 further comprising:

after the deforming, deflating the balloon.

24. The method defined inclaim 23 further comprising:

after the deflating, removing the balloon from inside the connector and from the patient.

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