US20020004680A1 - Anti-stenotic method and product for occluded and partially occluded arteries - Google Patents

Abstract

Methods of artificially lining a vessel, especially an artery, of a medical patient to address the existence of a flow-inhibiting atheroma and to significantly alleviate the probability of restenosis, and the resulting products.

Description

FIELD OF THE INVENTION
• The present invention relates generally to restoration of flow capacity to occluded and partially occluded vessels, including arteries, and more particularly to a procedure by which at least an interior lining is in the form of a vascular graft placed in an artery as an anti-stenotic measure.[0001]
BACKGROUND
• During the last thirty (30) years the most common technique for treating arterial stenosis has been surgical construction of a bypass conduit around the site of the occlusion. Bypass grafting in a symptomatic patient with a partially or totally occluded or stenotic superficial femoral artery, using a vein or prosthetic graft, has been the dominant technique for arterial reconstruction. Endarterectomy is also performed in some cases.[0002]
• In the last decade balloon catheter angioplasty of patients with focal stenosis has demonstrated benefit primarily because of its minimal invasiveness, thereby reducing cost and recovery time. It is, however, limited to short focal stenoses through which the balloon can be positioned. It has a significant rate of restenosis in longer or diffuse lesions, where its use is not indicated. To address these limitations and to improve the treatment of longer length segments of occlusive disease, a variety of catheter based laser and mechanical atherectomy devices have recently been developed and studied. The hope has been to obtain the benefits of reducing costs, morbidity, and recovery time available from using less-invasive, catheter-based methods while still obtaining the overall good patient results comparable to by-pass grafting. Despite these efforts, by-pass grafting has remained the technique generally used in clinical practice, due to its superior overall results compared to the novel catheter-based techniques heretofore developed. The present invention overcomes or substantially alleviates the limitations of previous catheter-based techniques for treating SFA disease, while obtaining the benefits of proven by-pass grafting techniques.[0003]
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
• In brief summary, the present invention overcomes or substantially alleviates the above-mentioned pre-existing problems. The present invention provides for removal of all or nearly all atheroma from within an arterial segment of any length and then placement of a vascular graft, which may be of any suitable material, with only one point of entry. The atheroma alone can be removed or the atheroma and the tunica intima alone or together with the tunica media of the arterial segment can be removed. Other vessels can also be treated and vascularly lined without departing from the scope of the invention. The present invention provides the benefits of minimally invasive surgery, overcomes or substantially alleviates the limitation of recurrent stenosis, and allows treatment of any occlusive lesion regardless of length.[0004]
• Thus, normal capacity blood flow is provided with no or low probability of recurring stenosis. While the present invention has been applied to occlusion in the superficial femoral artery, it is not limited to any particular artery diseased by stenosis.[0005]
• With the foregoing in mind, it is a primary object of the present invention to provide an antistenotic method and product by which substantially full blood flow capacity is restored to a wholly or partially occluded artery.[0006]
• Another object of importance is the provision of a method and product by which an atheroma is removed from an artery and provision is made to prevent or alleviate the likelihood of a later redevelopment of another atheroma at the removal site.[0007]
• A further significant object is to provide a method and product by which substantially full blood flow is surgically restored to a stenotic artery.[0008]
• Another dominant object is the provision of a method and product which substantially eliminates an atheroma from an artery and eliminates or significantly reduces the likelihood of restenosis at the prior atheroma site.[0009]
• An additional object of substantive importance is the provision for removal of stenotic deposits from an artery with or without removal of an interior portion of the artery followed by insertion of a vascular graft along the length of the removal site as an anti-stenosis measure.[0010]
• One more object of value is the provision of a method of and product for substantially removing stenotic deposits in an artery and substantially preventing or alleviating recurrence thereof independent of the arterial length of the deposits.[0011]
• An additional paramount object is the provision of a novel method and product by which a vessel of a medical patient is lined for the purpose of establishing and/or maintaining full blood flow.[0012]
• These and other objects and features of the present invention will be apparent from the detailed description taken with reference to the accompanying drawings.[0013]
BRIEF DESCRIPTION OF THE DRAWINGS
• The Figures described briefly below are line drawing schematics, predicated upon the existence and commercial availability of the various devices and apparatus as shown therein.[0014]
• FIG. 1 is a line drawing diagrammatically illustrating in cross-section a single arteriotomy in an occluded superficial femoral artery of a medical patient;[0015]
• FIG. 2A is a line drawing schematically illustrating in cross-section a double arteriotomy in an occluded superficial femoral artery of a medical patent;[0016]
• FIG. 2B is a line drawing schematically illustrating in cross-section access using a hollow needle to a site upstream of an atheroma in a superficial femoral artery of a patient;[0017]
• FIG. 3 is a line drawing diagrammatically illustrating in cross-section the atheroma of FIG. 1 with a guide wire extending through the atheroma;[0018]
• FIG. 4 is a line drawing diagrammatically illustrating in cross-section placement of a dynamic wire guide through the arteriotomy sufficient for the distal region of the dynamic wire guide to extend completely through the atheroma accommodating passage of a guide wire through a lumen in the dynamic wire guide before the dynamic wire guide is withdrawn;[0019]
• FIG. 5 is a line drawing diagrammatically illustrating in cross-section the advancement of a dynamic disrupter, over a guide wire for traversing the stenotic obstruction site in the superficial femoral artery;[0020]
• FIG. 6 is a line drawing diagrammatically illustrating in cross-section the advancement of a coring catheter along a guide wire spanning the atheroma obstruction in the artery to enlarge the lumen by removal of plaque;[0021]
• FIG. 7 is a line drawing diagrammatically illustrating in cross-section the artery showing an expandable cutting catheter or atherotome displaceable along the guide wire and expansion of blades of the cutter so as to cut plaque from the atheroma, using as many passes as appropriate with or without flushing or irrigating of the lumen;[0022]
• FIG. 8 is a line drawing diagrammatically illustrating in cross-section removal of the tunica ultima endothelium and tunica media collectively from an artery at a natural interface of weakness existing between the tunica media and the tunica adventitia;[0023]
• FIG. 9 is a line drawing diagrammatically illustrating in cross-section separation of a length of the tunica intima endothelium together with the tunica media from the tunica adventitia along a natural interface of weakness using a Hall loop;[0024]
• FIG. 10 is a line drawing diagrammatically illustrating in cross-section a vascular graft according to the present invention having collapse resistant characteristics placed in the knee of a patient;[0025]
• FIG. 11 is a line drawing diagrammatically illustrating in fragmentary cross-section use of a Scanlan Endarsector to separate conjointly a length of the tunica intima endothelium and tunica media from the tunica adventitia along a natural interface of weakness;[0026]
• FIG. 12 is a line drawing diagrammatically in cross-section a Simpson Atherocath performing an atherectomy;[0027]
• FIG. 13 is a line drawing diagrammatically illustrating in cross-section performance of a balloon angioplasty;[0028]
• FIG. 14 is a line drawing diagrammatically illustrating in cross-section the performance of an atherectomy using a laser;[0029]
• FIG. 15 is a line drawing diagrammatically illustrating in cross-section performance in an artery of ultrasound angioplasty;[0030]
• FIG. 16 is a line drawing diagrammatically illustrating in perspective one suitable pre-formed cylindrical or sleeve-shaped vascular graft for lining arteries in accordance with the present invention;[0031]
• FIG. 17 is a line drawing diagrammatically illustrating in perspective a tapered, pre-formed vascular graft for carrying out the present invention;[0032]
• FIG. 18 is a line drawing diagrammatically illustrating in perspective, with parts broken away for clarity, the utilization of a vascular graft, pre-formed and cylindrical or sleeve-shaped in configuration, having internal ring reinforcements;[0033]
• FIG. 19 is a line drawing diagrammatically illustrating in perspective, with parts broken away for clarity, a vascular graft, pre-formed and cylindrical or sleeve-shaped in configuration, having internal helically-shaped reinforcement, for carrying out the present invention;[0034]
• FIG. 20 is a line drawing diagrammatically illustrating in perspective a bifurcated vascular graft for carrying out the present invention;[0035]
• FIG. 21 is a line drawing diagrammatically illustrating in perspective a vascular graft, pre-formed and cylindrical or sleeve-shaped in configuration, having tissue in-growth material along a portion of the exterior surface thereof;[0036]
• FIG. 22 is a line drawing diagrammatically illustrating in perspective, with a portion broken away for clarity, a vascular graft, pre-formed and cylindrical or sleeve-shaped in configuration, having an expandable stent internally sutured at the distal end thereof in the contracted state, for carrying out the present invention;[0037]
• FIG. 23 is a line drawing diagrammatically illustrating in cross-section placement of a dilator/sheath along a guide wire into the artery for placement of a vascular graft;[0038]
• FIG. 24 is a line drawing diagrammatically illustrating in cross-section the sheath of FIG. 23 with the distal portion thereof in the artery after the dilator has been removed;[0039]
• FIG. 25 is a line drawing diagrammatically illustrating in elevation a vascular graft placement mandrel having a vascular graft attached to the mandrel shaft for placement in an artery;[0040]
• FIG. 26 is a line drawing diagrammatically illustrating in cross-section of the vascular graft and the distal end of the mandrel of FIG. 25 being advanced into the artery through the sheath of FIG. 24;[0041]
• FIG. 26A is a cross-section taken along[0042]line26A-26A of FIG. 26;
• FIG. 27 is a line drawing diagrammatically illustrating in cross-section partial removal of the sheath of FIG. 25 after the distal end of the mandrel shaft and the vascular graft has been placed in the desired position in the artery through the sheath, with the graft being held by the mandrel while the sheath is withdrawn;[0043]
• FIG. 28 is a line drawing diagrammatically illustrating in cross-section the existence of the vascular graft in the artery after both the sheath and the mandrel have been removed therefrom;[0044]
• FIG. 29 is a line drawing diagrammatically illustrating in cross-section a balloon catheter disposed in the vascular graft after the graft has been positioned as illustrated in FIG. 28;[0045]
• FIG. 30 is a line drawing diagrammatically illustrating in cross-section the vascular graft firmly contiguous with the inside surface of the artery after the vascular graft has been expanded by use of the balloon catheter illustrated in FIG. 29 and the balloon catheter but not the guide wire has been removed;[0046]
• FIG. 31 is a line drawing diagrammatically illustrating in cross-section the disposition of the vascular graft in the artery after all other paraphernalia has been removed;[0047]
• FIG. 32 is a line drawing diagrammatically illustrating in cross-section the vascular graft of FIG. 32 linearly disposed within and sutured proximally near the wall of the superficial femoral artery;[0048]
• FIG. 33 is a line drawing diagrammatically illustrating in cross-section grasping of the distal end of a vascular graft in the treated artery using forceps;[0049]
• FIG. 34 is a line drawing diagrammatically illustrating in cross-section a vascular graft, sutured at the distal end thereof to the distal end of a mandrel both disposed in a treated artery;[0050]
• FIG. 35 is a line drawing diagrammatically illustrating in cross-section placement of the distal end of a vascular graft in an artery by use of a placer/suturer;[0051]
• FIG. 36 is a line drawing diagrammatically illustrating in fragmentary cross-section the securing of both ends of a vascular graft in an artery using one or more sutures at each end;[0052]
• FIG. 37 is a line drawing diagrammatically illustrating in fragmentary cross-section securing of a vascular graft in a treated artery using staples at both the distal and proximal ends of the vascular graft;[0053]
• FIG. 38 is a line drawing diagrammatically illustrating in cross-section a vascular graft secured at its distal end in an artery using an expanded stent;[0054]
• FIG. 39 is a line drawing diagrammatically illustrating in cross-section placement of a coating on the treated interior surface of an artery to form in place a vascular graft.[0055]
• FIG. 40 is a line drawing diagrammatically in cross-section a balloon catheter having the balloon thereof partially inflated within a vascular graft prior to joint insertion into a treated artery; and[0056]
• FIG. 41 is a line drawing diagrammatically in cross-section the partially inflated balloon catheter and vascular graft after placement in a treated artery.[0057]
DETAILED DESCRIPTION OF THE PRFERRED EMBODIMENTS
• Introduction[0058]
• The illustrated embodiments demonstrate and are representative of methods by which a partially or totally occluded artery or other vessel of a patient is recanalized and the risk of restenosis is substantially reduced or eliminated by use of a vascular graft within the treated artery.[0059]
• While the present invention may be used in a vessel other than an artery, the primary benefit lies in application to an artery. Artery flow is either conduit or branch flow. The iliac, femoral, and more distal arteries are most likely to occlude, either totally or partially. All arteries are strong, durable, three-layer vessels while veins are thin, single layer conduits. The arterial wall layers are, inside out, the tunica intima endothelium (intima), the tunica media (media), and the tunica adventitia (adventitia). It has been found that in diseased arteries typically the interface between the adventitia layer and the media layer becomes a region of naturally occurring weakness. In fact, it has been found that plaque not only accumulates within the lumen of the artery but infiltrates both the intima and media causing a tissue breakdown there.[0060]
• Removal of the intima and the media from the adventitia and leaving the adventitia of the artery is called an endarterectomy.[0061]
• The primary cause of artery occlusion is build-up of plaque, the density of which ranges between very soft to rock-hard calcified deposits. Plaque deposits may form in some arteries and not at all or slightly in other arteries of the same person. A plaque deposit in a specific area or region of an artery is sometimes called an atheroma.[0062]
• Under appropriate anesthesia the artery is exposed, clamped, and at least a single arteriotomy is performed distal to the clamp and proximal to the occlusion. Under some circumstances two arteriotomies are performed, one upstream and the other downstream of the atheroma although a single arteriotomy is preferred. In some situations access to the artery can be by use of percutaneously placed hollow needle, instead of by use of an arteriotomy.[0063]
• In situations where an arteriotomy is the preferred choice, a guide wire is advanced through an upstream arteriotomy until the guide wire extends beyond the atheroma. Sometimes a guide wire can be advanced through a clogged artery, but not always. In situations where a guide wire alone cannot cross the atheroma, a dynamic wire guide or a dynamic disrupter is preferably used to centrally loosen and/or displace the centrally disposed plaque followed by central insertion of the guide wire through the hollow interior in the dynamic wire guide or disrupter. Thereafter, the dynamic wire guide or disrupter is removed.[0064]
• Any technique by which the plaque is severed from the inner wall of the intima is called an atherectomy. Typically, plaque may be so severed by a coring catheter or by using an atherotome having one or more expandable blades to accommodate insertion and one or more passes through the atheroma, each pass at an increased blade diameter.[0065]
• Atherectomy devices such as a Simpson Atherocath, an Auth Rotablator, a Kensey device, or an Intervertional Technologies Transluminal Extraction Catheter (TEC device) may be used.[0066]
• In some situations an endarterectomy is the preferred medical choice. For example, an endarterectomy is often best when the disease of the artery is substantially advanced, causing a natural interface of weakness between the media and the adventitia. A cutting atherotome may be used to initially cut through the diseased intima and media to the adventitia at the distal end of the site of the endarterectomy creating a taper at that location followed by advancement in a proximal direction until the entire undesired length of intima and media have been excavated. Alternatively, the intima and media may be cut radially or on a bevel adjacent both a first and second arteriotomy located above and below the atheroma. Ideally, a taper is used at both ends of the endarterectomy where the enlarged lumen produced connects across a beveled tapered to the normal lumen of the artery, both distally and proximally the dispensed material is loosened from the wall using any suitable instrument, such as a surgical spatula. Forceps may be used to grasp and pull upon a loosened part of the intima and media to be removed causing the intima and media between the two cuts together with the atheroma contained therein to be removed from the artery as a cylindrical unit.[0067]
• Alternatively, a Hall loop may be advanced from one arteriotomy to the other after the two above-mentioned cuts have been made. The loop, in the nature of a piano wire loop held on the end of a staff is positioned at the above-mentioned natural interface of weakness. The loop is positioned at and displaced along the interface by pushing on the staff until the intima, the media, and the atheroma to be removed have been unitarily severed following which the cylindrical unit may be grasped and removed from the artery using forceps, for example. similarly, a Scanlan Endarsector or a cutter having rotating blades may be used to assist in the performance of the endarterectomy.[0068]
• In situations where an angioplasty, in whole or in part, is the treatment of choice, an instrument of expansion is used to enlarge or open and enlarge the blood flow accommodating lumen at the atheroma. Mechanical instruments, equipment for performing balloon angioplasty, laser instruments, and instrumentation for ultrasound angioplasty may be used to achieve the angioplasty.[0069]
• Once the plaque has been excavated, steps are taken to line the remaining treated arterial or vessel wall. The resulting lining is herein referred to as a vascular graft. Vascular graft, as used herein, is intended to mean any of the following: 1. conventional and novel artificial grafts made of any material, including but not limited to fabrics such as dacron, or expanded PTFE Gortex™ thin wall sleeve material, in any density from very soft and low density to very stiff and high-density, constructed in any shape including straight, tapered, or bifurcated, and which may or may not be reinforced with rings and spirals or other reinforcement, and which may or may not have one or more expandable stents incorporated into the graft at one or both ends or along its length, 2. natural artery or vein material taken from human or animal donors, 3. stents, 4. coating applied to the inside of the treated arterial wall which forms a patent lumen or is biologically active and causes the lining of the vessel or duct to form a patent lumen, and 5. any combination of the foregoing vascular graft options. The exterior of the vascular graft or part of it may and preferably does comprise tissue in-growth material. where a pre-formed tubular vascular graft of synthetic material is used, the material thereof may be and preferably is dimensionally stable. However, if desired, it may be radially expandable material.[0070]
• The vascular graft of choice may be introduced into the treated artery or other vessel in any suitable way including but not limited to use of a dilator/sheath, placement of the vascular graft upon a mandrel shaft and/or use of long-nose forceps. The distal ends of the tubular graft and the mandrel shaft may be temporarily sutured together or the distal end of the vascular graft sutured together over the mandrel to accommodate unitary displacement into the vein, for example through a sheath after the dilator has been removed.[0071]
• Where the material of which the vascular graft is formed is expandable and in tubular or sleeve form, once the sheath has been removed the diametral size of the graft may be enlarged in contiguous relationship with the inside arterial surface using a balloon catheter. A balloon catheter may also be used to bring a folded or partially collapsed vascular graft which is dimensionally stable into contiguous relation with the interior surface of the remaining artery wall.[0072]
• The tubular graft may also comprise a biologically inert or biologically active anti-stenotic coating applied directly to the treated area of the remaining arterial inner surface to define a lumen of acceptable blood flow capacity.[0073]
• The graft, once correctly positioned and contiguous with the interior vascular wall, is usually inherently secure against inadvertent migration within the artery or other vessel due to friction and infiltration of weeping liquid accumulating on the inside artery wall. It is preferred that the length of the vascular graft be selected to span beyond all of the treated region of the artery.[0074]
• One or both ends of the vascular graft may be sutured or surgically stapled in position on the treated wall to prevent undesired displacement or partial or complete collapse under cardiovascular pressure. In particular, the upstream end of a graft placed in an artery must be secure to prevent a flap of the graft from being pushed, by arterial blood flow, into a position where it occludes, in whole or in part, the vessel. One or both ends may be held open by one or more stents disposed within the tubular graft. Forceps may be used to hold a free end of the vascular graft while the other end is secured to the vascular wall. Currently, it is preferred to secure the proximal end of the tubular vascular graft to the treated vascular wall and to bias dilate the distal end of the tubular vascular graft by use of a balloon catheter and/or arterial pressure. Where the distal exterior of the sleeve-shaped vascular graft comprises tissue in-growth material, as is preferred as in-growth occurs it becomes immaterial how the initial dilating bias was achieved.[0075]
• The Illustrated Embodiments[0076]
• Reference is now made to the drawings wherein like numerals are used to designate like parts throughout. While the drawings are specifically directed toward the removal of an atheroma in the superficial femoral artery, it is to be appreciated that the principles of the present invention apply to other arteries as well as to ducts and vessels in the body other than arteries. specifically, FIG. 1 illustrates the juncture between the common femoral artery and the superficial femoral artery and profunda femoris artery, respectively located at a site near the groin of a medical patient. FIG. 1 further illustrates the existence of a surgically created[0077]arteriotomy50 providing access to the superficialfemoral artery52 at a location proximal of an atheroma, generally designated54. Theatheroma54 comprises a centrally located, relatively softcentral plaque portion56 surrounded by a calcifiedplaque portion58.
• FIG. 2A is similar to FIG. 1 and further illustrates a[0078]second arteriotomy50′ located distal of theatheroma54, providing a second access site to theartery52, as explained herein in greater detail.
• FIG. 2B illustrates the[0079]same artery52 to which access is provided solely by percutaneous placement of aneedle60 into the hollow of theartery52 upstream (proximal) of theatheroma54.Needle60 accommodates plaque removal and placement of a lining within theartery52.
• While FIGS. 1, 2A, and[0080]2B illustrate an atheroma which completely occludes theartery52, it is to be appreciated that the present invention applies to both partial and complete occlusion due to plaque. The overall objective is to restore substantially full blood flow to the artery and prevent restenosis. It is to be appreciated that the artery receiving treatment is temporarily deprived of blood flow altogether, using known methods of temporary occlusion. Prior to temporary occlusion, systemic or regional heparinization may be effected.
• Typically, as illustrated in FIG. 3, after the[0081]arteriotomy50 has been made near the origin of the superficial femoral artery, aguide wire62, conventional in construction, is advanced distally through thearteriotomy50 and through theatheroma54 along thesofter plaque portion56 thereof. If theguide wire62 alone cannot be manually caused to traverse theatheroma54, as illustrated in FIG. 3, other medical instruments may be used to create a passageway through theatheroma54 following which theguide wire62 may be appropriately inserted so as to traverse theatheroma54. For example, adynamic wire guide64 may be advanced and operated so as to create a lumen through thesofter plaque56 of theatheroma54 as diagrammatically illustrated in FIG. 4. Currently, the preferred dynamic wire guide is the one disclosed in pending U.S. patent application Ser. No. 07/973,514, filed Nov. 9, 1993, assigned to EndoVascular Instruments, the assignee of the present application, although other dynamic and static wire guides could be used.
• Once the[0082]dynamic wire guide64 has penetrated thecentral plaque region56 so as to traverse thehard plaque portion58, theguide wire62 is advanced through the lumen within thedynamic wire guide64, following which the dynamic wire guide is withdrawn leaving theguide wire62 in position, as a guide for instruments by which the soft andhard plaque56 and58 are removed.
• Alternatively, with reference to FIG. 5, a[0083]dynamic disrupter66, having a rotating enlargedrounded tip67, may be used in lieu of the dynamic wire guide described above to penetrate thesofter plaque region56 sufficient to accommodate concentric insertion of theguide wire62 through thedynamic disrupter66, with thedynamic disrupter66 after being removed along the guide wire while the guide wire is retained in its inserted position. Currently, the preferred dynamic disrupter is the one disclosed in pending U.S. patent application Ser. No. 07/973,514, filed Nov. 9, 1993, assigned to EndoVascular Instruments, the assignee of the present application, although other dynamic disrupters could be used.
• While not shown, it is to be appreciated that plaque, separated from the[0084]atheroma54, cannot be allowed to remain uncollected within the artery and, therefore, conventional instruments and procedures are used appropriately downstream of theatheroma54 to collect and remove all debris released during treatment of theatheroma54.
• Having established the appropriate placement of[0085]guide wire62 through theatheroma54, the surgeon is in a position to enlarge the arterial lumen at the site of theatheroma54 by removingplaque58. Such removal is commonly referred to as an atherectomy. The severing, grinding, cutting, chipping, and abrading of theplaque58 may be mechanically accomplished by any suitable cutting instrument. Exemplary types are illustrated in FIGS. 6 and 7, respectively. FIG. 6 illustrates diagrammatically utilization of acoring catheter70, advanced along theguide wire62 through thearteriotomy50 so as to cut theplaque58 from theartery52 using as many passes along theatheroma54 as necessary. The coring catheter has a cuttinghead72 which is caused to be rotated by the surgeon. It is currently preferred that thecoring catheter70 be that which is disclosed in the assignee's co-pending U.S. patent application Ser. No. 07/973,514, which was filed Nov. 9, 1992, although any suitable coring catheter may be utilized.
• Either in conjunction with a coring catheter or in lieu thereof, the lumen across the[0086]atheroma54 can be enlarged using an expandable cutter, having diametrally expandable cutting blades as illustrated in FIG. 7. Theexpandable cutter74 is initially advanced along theguide wire62 in an unexpanded state.Expandable cutter74 has a diametrallyadjustable cutting head76 which, when expanded and pulledforward atherectomy50 will cut or shave the plaque atdeposits58. Alternatively, the expandable cutter may be utilized in a fashion in which the expandable cutting blades, when expanded, engage and grab hold of a section of the plaque. When the expandable cutter is pulled, it both cuts the junction with the remaining distal plaque and allows a cylindrical length of the plaque which lies proximal of the cutting blades to be removed all in one segment. Typically, a plurality of passes of the cuttinghead76, each with a slightly greater diameter are required to completely excavateplaque58. Currently, it is preferred that the expandable cutter disclosed in assignee's U.S. Pat. No. 5,211,651 be utilized.
• Attention is now turned to those situations where an endarterectomy is the procedure of choice. Specific reference is now made to FIG. 8 which illustrates, in part, one way in which the[0087]intima100 and themedia102 are collectively separated from theadventitia104 along a natural interface ofweakness106, which typically exists in diseased arteries. A first andsecond arteriotomy50 and50′ may be made proximal and distal of the atheroma and a radial or tapered cut at or near each arteriotomy made through the intima and media layers to theinterface106. By loosening a length of the twointerior layers100 and102 of theartery52 from the adventitia along theinterface106 at the radial or beveled cut adjacent thearteriotomy50, the loosened part is available for grasping, using a suitable instrument such as forceps108 illustrated in FIG. 8. By pulling one or more times in the general direction ofarrow110 so as to have a substantial axial-component along the length of theartery52, the cut length of intima and media is severed alonginterface106 and pulled from the artery througharteriotomy50.
• While not illustrated in all of the Figures (for simplicity of presentation), it is to be appreciated that all arteries comprise three layers, the intima, the media, and the adventitia.[0088]
• It is to be understood that the distinction between atherectomy and endarterectomy is somewhat arbitrary, as it depends upon whether the material being removed consists exclusively of atheroma only, or of a combination of atheroma and material characteristic of the inner lining of the vessel. Pathology analysis of such removed material frequently indicates the presence of cells and other material characteristic of both plaque and the media and intima, so it is probably most correct to refer to this procedure as an endarterectomy.[0089]
• In one currently preferred embodiment, an endarterectomy is performed using the dynamic disrupter and the expandable cutter. The dynamic disrupter is first advanced over the guide wire both to loosen the plaque and the intima and media along the natural interface of weakness, and to enlarge the channel or lumen through the artery. The dynamic disrupter may be advanced one or more times. If multiple advances are used, the repeated advancements may be done using the same tip size, or they may be done using successively larger tip sizes.[0090]
• After the dynamic disrupter has been used and withdrawn over the guide wire, the expandable cutter is employed to remove the material that has been loosened. With the blades unexpanded, the expandable cutter is advanced a suitable distance into the atheromatous region, and then the blades expanded. When the expandable cutter is withdrawn, it engages the plaque and arterial lining, and exerts force upon the natural interface of weakness. The plaque and arterial lining are withdrawn by the expandable cutter in the form of a cylindrical plug of material, which may be short or long depending upon how far into the plaque the cutter is advanced before it is expanded. After removing the plug of material from the cutter, the blades are returned to the unexpanded position and re-advanced into the artery, this time to a position further than the previous advancement, so that a new length of atheromatous material can be engaged. The blades are once again expanded, and a new plug of material is engaged and withdrawn. By a repeated series of such steps, any desired length of artery may be excavated of its plaque and inner lining. When the final advance to the most distal point is performed, the distal tapered shape that the blades assume when expanded leaves behind the desired tapered shape as it cuts and removes the final plug of material from the artery. This eliminates any need to make the[0091]second arteriotomy50′, for the purpose of making the distal radial cut, when the expandable cutter is employed.
• In the alternative, an endarterectomy may be performed using a Hall loop, as diagrammatically illustrated in FIG. 9. Preliminarily, the artery containing the[0092]atheroma54 is accessed, as illustrated in FIG. 2A, by first and second arteriotomies50 and50′. The first radial or beveled cut through the intima and media is made, as described above, and the media is severed alonginterface106 at one end or the other (usually the upstream, proximal end) for a short distance to allow theloop110 to be placed at the interface, with theflexible shaft112 extending in the direction of the pull and through the more remote arteriotomy. When power is applied, the loop is caused to oscillate as the Hall loop is advanced along theinterface106 until complete severance has occurred, following which forceps may be used to pull the removed intima and media layers from the artery through the proximal arteriotomy after the second radial or beveled cut through the intima and media is made, attempting to leave a tapered contour to the remaining material at the distal end of the endarterectomy. The Hall loop is more fully described in U.S. Pat. No. 3,730,185.
• The endarterectomy may similarly be performed using a Scanlan Endarsector, as generally illustrated in FIGS. 10 and 11. It is to be appreciated that the[0093]Scanlan Endarsector114 is a commercially available instrument, sold by Scanlan International, Inc., 1 Scanlan Plaza, St. Paul, Minn. 55107, and may be used alone or in conjunction with other instruments to perform the endarterectomy. TheScanlan Endarsector114 comprises a handle (not shown) from which an elongated U-shaped shaft extends. By probing with the Scanlan Endarsector along theinterface106 adjacent portions of themedia102 andintima100 which have been loosened, further loosening occurs until the endarterectomy is completed and the severed artery portion removed.
• Reference is now made to FIGS. 12 through 15 which illustrate various ways in which an atherectomy may be performed when that procedure is the treatment of choice, in whole or in part, for enlarging the blood flow lumen of[0094]artery52 atatheroma site54.
• With specific reference to FIG. 12, there is illustrated a mechanical instrument for the performance of an atherectomy, i.e., Simpson Atherocath, generally designated[0095]116. The atherocath comprises an outside,hollow shaft118 through which extends a rotatableinner shaft120 to which arotating cutter head122 is non-rotatably attached. Therotating cutting head122cuts plaque58 from the interior of theartery52 as the atherocath is advanced. Aballoon124 is inflated on the side opposite the cuttinghead122 to thereby bring pressure to bear against the artery and urge the cutting head firmly against the plaque. At the distal end of the atherocath is located achamber126, which functions to collect plaque shavings removed by the cuttinghead122. Theatherocath116 is inserted and removed alongguide wire62. The Simpson Atherocath is commercially available from Devices for Vascular Intervention, division of Eli Lilly, 26201 YNEZ Road, Temecula, Calif. 92591.
• FIG. 13 diagrammatically represents the use of balloon angioplasty to enlarge the lumen of an atheroma-ridden artery. Specifically, a[0096]balloon302 of aballoon catheter300 is advanced alongguide wire62 until it is disposed within theatheroma54. Using the side port of theballoon catheter300, theballoon302 is expanded, which radially expands theplaque58. This process ordinarily creates cracks in the plaque, but nevertheless results in an enlarged lumen through theplaque58 although, typically, theplaque58 is not intentionally removed.
• Reference is now made to FIG. 14 which diagrammatically illustrates use of a laser instrument, generally designated[0097]130 to removeplaque58 fromartery52. Thelaser instrument50 comprises asource132 of laser energy. The laser energy is processed along a bundle of optical fibers disposed within acatheter134.Laser beams136 are emitted from theinstrument130 through a plurality of laser emitters138. Thelaser beams136 cut plaque fromdeposits58 as the distal end of thecatheter134 is advanced distally into theplaque58. Thelaser instrument130 is illustrated as being concentrically disposed uponguide wire62 for insertion, advancement, and ultimate removal. Thus, an atherectomy may be performed in accordance with the principles of the present invention by use of one or more laser beams. A suitable laser instrument is the Laserprobe PLR or Lasercath-PRL, used with the Optilase Laser Source System, all of which are available from Trinedyne, Inc., 1815 East Carnegie Avenue, Santa Ana, Calif. 92705.
• In lieu of the above-mentioned ways for performance of an atherectomy, or in conjunction therewith, ultrasound energy may be used. Specific reference is made to FIG. 15 which illustrates diagrammatically an ultrasound instrument, generally designated[0098]140.Instrument140 comprises a source of ultrasound energy, i.e.,ultrasound transducer142.Transducer142 connects via anultrasound shaft144 to anultrasound head146. Theultrasound shaft144 is substantially concentrically disposed within anultrasound catheter148. A guide wire is not used. Release of ultrasound energy fromhead146 is caused to impinge uponplaque58 fracturing the same progressively, thereby enlarging the blood flow lumen of theartery52. A suitable ultrasound instrument for removal of plaque is the Sonocath, available from Angiosonics, Wayne, N.J., (201) 305-1770.
• Once the interior of the partially or totally occluded artery has been treated using an appropriate procedure including one or more of the procedures described above, the present invention includes placement of a lining or vascular graft so as to extend preferably co-extensively along the full length of the treated portion of the artery. The nature of the vascular graft will vary depending upon the circumstances, the artery in question, the length over which the artery has been treated, and perhaps other factors. The vascular graft may be of any suitable biologically inert material including, but not limited to, a dacron sleeve of medical grade fabric, a sleeve of expanded PTFE (such as GOR-TEX™ polytetrofluoroethelene vascular graft tubing available from W. L. Gore and Associates, Inc., Medical Products Division, 1505 N. 4th Street, Central Dock 3, Flagstaff, Ariz. 86002). Another available sleeve formed of expanded PTFE is available from IMPRA, Inc., P.O. Box 1740, Tempe, Ariz. 85280-1740.[0099]
• The material may be dimensionally stable or capable of being expanded, for example, using a balloon catheter and/or one or more stents. For short lengths, vascular graft[0100]200 (FIG. 16) may be used.Vascular graft200 is illustrated as having blunt ends, is cut to a length commensurate with the treated artery and comprises exterior and interior surfaces respectively comprising a uniform diameter along the entire length of thevascular graft200. The wall thickness is also illustrated as being uniform.
• For longer lengths, tapered vascular graft[0101]202 (FIG. 17) may be preferable, the degree of taper being selected so as to match the taper of the artery subjected to one or more of the treatments described above.
• In cases where the artery being lined is bifurcated (e.g., comprises a branch from one to two arteries), vascular graft[0102]204 (FIG. 20) may be used, the configuration thereof being adapted to conform specifically to the nature of the shape, size, and disposition of the branched artery subjected to treatment. Depending upon the anatomy,vascular graft204 may be straight or tapered or straight in part and tapered in part.
• When strength greater than the mere material from which a vascular graft is formed becomes a consideration, the vascular graft may be reinforced, particularly when no expansion thereof is required during placement. Two typical forms of reinforcement are illustrated in FIGS. 18 and 19, respectively, which depict[0103]vascular graft206 andvascular graft208, respectively.Vascular graft206 comprises reinforcement in the form of a plurality ofrings210. While illustrated as being embedded within the material212 from which thevascular graft206 is formed, the reinforcing rings could be placed either internally or externally in respect to thegraft206 itself.
• Similarly,[0104]vascular graft208 is illustrated in FIG. 19 as comprising a continuous,helical reinforcement214 embedded in the material216 from which thevascular graft208 is formed. Thereinforcement214 could be placed as well either internally or externally of thevascular graft208 itself.
• The reinforcement, e.g., rings[0105]210 and helix24 can be of any suitable biologically inert material such as an implantable grade of thermoplastic material, e.g., polypropylene or nylon.
• Even in cases where sutures, staples, and/or stents are used to initially hold the lining or vascular graft contiguously against the treated artery wall, utilization of tissue in-growth material at the exterior of all or part of the vascular graft may be desirable. In this regard, specific reference is made to FIG. 21 which diagrammatically illustrates the existence of tissue in-[0106]growth material220 disposed along approximately the distal one-half of the hollow cylindrically-shapedvascular graft222. The value of the tissue in-growth material is that it becomes, in due course of time, the primary connector between the treated arterial surface and the vascular graft.
• With reference to FIG. 22, there is diagrammatically illustrated a hollow cylindrical[0107]vascular graft224 to which anexpandable stent226 has been connected interiorly at the proximal end thereof usingsutures228. Once thevascular graft224 is properly positioned within a treated artery, thestent226 is conventionally expanded to bias the proximal end of thevascular graft224 contiguously against the treated arterial surface to retain the position of placement. This condition is illustrated in FIG. 38. While illustrated as being placed internally inside ofgraft224, the stent could also be placed externally or it could be embedded within the material from which thevascular graft224 is formed.
• Utilization of a vascular graft within the context of the present invention significantly tends to provide a barrier between the bloodstream and the vessel wall which is believed to reduce restenosis, provides a conduit through which the blood can flow which is known to be well-tolerated by the bloodstream, preserves the area available for blood flow, prevents an aneurysm, promotes rapid healing without excessive weeping or adhesion of blood at the lining site between the vascular graft and the adventitia layer, and provokes minimal scarring. Plaque, it has been determined, does not form on and adhere to the vascular graft.[0108]
• In lieu of a pre-formed straight or tapered sleeve (with or without a bifurcation) the treated arterial wall, e.g., at[0109]interface106, may be lined using a liquid coating of suitable material applied as a spray or otherwise and allowed to cure until a hollow lumen is defined within the cured coating and the treated arterial surface is concealed by the coating, or allowed to remain in place long enough to cause the artery to form a stable, hollow lumen. In this regard, reference is made to FIG. 39 which illustrates the presence of a manually controllednozzle230 forming a part of a surgical spraying instrument by which acoating232 is applied to the treated arterial surface atinterface106. Suitable coatings, for example, having the requisite biologically inert characteristics and wall adherence characteristics would include pharmaceutical-grade collagen available from Collagen Corp., 1850 Embariadero Road, Palo Alto, Calif. 94303.
• Once the vascular graft of choice has been selected, other than an in-place coating, insertion of the vascular graft into the treated artery must be achieved. It is currently preferred to use a commercially available dilator/peel-away sheath generally designated[0110]250 (FIGS. 23, 24,26, and27). However, a solid (non-peel-away) sheath may also be utilized or the graft may be inserted directly into the vessel without use of a sheath. As is well known in the art, the dilator/sheath250, in assembled condition, is passed concentrically along theguide wire62 through the access opening to theartery52. The access opening may be an arteriotomy50 or a percutaneous venipuncture caused by insertion of needle60 (FIG. 2B) followed by advancement of the guide wire through theneedle60 and subsequent removal of the needle. In the case of a needle puncture, thedilator252 at the tapereddistal tip254 enlarges the radial size of the puncture as does the sheath256 (slightly) as the dilator-sheath250 is advanced through the puncture concentrically around theguide wire62 until the dilator-sheath250 is positioned as illustrated in FIG. 23. Once the position of FIG. 23 has been achieved, the medical attendant simply manually retracts the dilator along theguide wire62 until it is fully removed, leaving thesheath256 in place with the proximal end thereof exposed, as diagrammatically illustrated in FIG. 24.
• Next, steps are taken to insert the vascular graft through the sheath and locate the graft in the treated artery so as to be, preferably, at least co-extensive with the treated artery surface, with the guide wire inside the graft. The treated artery surface shown in FIGS.[0111]23-24 and26-27 isinterface106. One way in which insertion may be consummated is by use or a graft placement long-nose forceps, generally designated260 (FIG. 25) which comprises a control handle262 from which amandrel shaft264 distally extends. Activation of thecontrol262 causes bifurcatedtips266 located at the distal end of themandrel shaft264 to open and close, to grasp or clamp and release, respectively, thedistal end268 of a hollow tubularvascular graft270. By grasping betweentips266 thedistal end268 of thevascular graft270, the vascular graft follows themandrel shaft264 as it is advanced over theguide wire62 and through thesheath256 as illustrated in FIGS. 26 and 27.
• With the[0112]graft270 correctly positioned in theartery52, theforceps260 andgraft270 are held in a stationary position, the forceps grasping the graft, as the sheath is withdrawn. In the case of peel-awaysheath256, as the sheath is withdrawn it is manually split into two pieces, as illustrated in FIG. 27, following which each piece is discarded.
• At this point, the[0113]forceps260 and thegraft270, with theguide wire62 passing centrally through the graft, are left in position and thesheath256 has been entirely removed. Thereafter, the guide wire andgraft270 are held stationary, themandrel control262 manipulated to open thetips266 causing thedistal end268 of thegraft270 to be released, following which theforceps260 are withdrawn while theguide wire62 and thegraft270 are retained in position as illustrated in FIG. 28.
• Alternatively, the sheath may be placed correctly in the[0114]artery52 using a hollow mandrel, generally designated280 (FIG. 34). Wherein thesheath270 is concentrically disposed around thehollow mandrel280 with the distal ends of each being sutured together usingapertures282 located in the distal end of themandrel280. By placing asuture284 helically through theapertures282 and through the adjacent thickness of thevascular graft270, the vascular graft and the mandrel are secured together. Where only one access opening, such asarteriotomy50, is used, thesuture284 may be extended through the hollow of themandrel280 and through thearteriotomy50 for access by the medical attendant. Once fully positioned in the artery, one end of thesuture284 is pulled by the medical attendant, causing the suture to helically unwind at the distal end of thevascular graft270 for complete removal of thesuture284, following which themandrel280 is fully retracted leaving thevascular graft270 correctly disposed in theartery52, with theguide wire62 inside the graft.
• Similarly, with or without a dilator/sheath, used in the manner described above, an elongated, long-nose forceps[0115]290 (FIG. 35) may be used as well for correct placement of thevascular graft270. Long-nose forceps290 may be of any suitable type, such as commercially available pediatric bronchoscopy forceps or retrieval forceps, such as Storz's. More specifically, theforceps290 comprise exposedjaws292 which are controlled at the proximal end of theforceps290 accommodating opening and closing of thejaws292. By creasing or folding at268 thevascular graft270 and forcing the crease or fold268 between thejaws292 when open accommodates clamping of the creaseddistal end268 when thejaws292 are tightly closed. Thereafter, theforceps290 and thevascular graft270 are jointly advanced through the access site, such asarteriotomy50, until thevascular graft270 is correctly located in the treatedartery52, as illustrated in FIG. 35. Thereafter, thejaws292 are opened, thefold268 at the distal end of thevascular graft270 is released and theforceps290 retracted leaving thevascular graft270 properly disposed within the artery Independent of the procedure used, thevascular graft270 is now correctly located in theartery52, with theguide wire62 passing through the center of thevascular graft270, as illustrated in FIG. 28.
• Insertion of a tubular graft of choice into the treated artery often involves folding or other forms of reduction in the diametral size occupied by the vascular graft during insertion, for example, to accommodate a size which will allow displacement through the[0116]sheath256. The sheath handle may accept a graft folded shown in FIG. 26A. This folded configuration may continue the length of the sheath, to allow the easier passage of the graft through the sheath, by de-forming the inside diameter to the shape, or by laying a conventional catheter or wire alongside the graft during insertion to create an indentation in the graft. For this reason and because, typically, the walls of a synthetic vascular graft are very supple and lack shape-retaining strength, the vascular graft, if left alone, tends to be and remain non-contiguous with the treated surface at the interior of the artery, e.g.,surface106, e.g., retaining the crimped or folded shape it assumes during insertion. In order to provide a contiguous relationship between the vascular graft and the adjacent arterial wall and to dilate the vascular graft to its full diameter, it is presently preferred that aballoon catheter300 of conventional, commercially available design be advanced concentrically around theguide wire62 until theballoon302 thereof is positioned within thesheath270 just inside the distal edge2681 of thesheath270. See FIG. 29.
• By sequentially expanding, deflating, slightly displacing and once more inflating, etc., the[0117]balloon302, thevascular graft270 is caused to become contiguous with and adhered to the adjacent arterial wall surface, following which theballoon302 is deflated and theballoon catheter300 retracted along the guide wire and discarded, leaving thevascular graft270 postured as illustrated in FIG. 30. Alternatively, one very long balloon catheter can be employed to perform this step in a single balloon expansion, andjor the balloon can be sized to exactly match the graft, e.g., tapered balloon used with tapered graft, etc.
• Thereafter, the[0118]guide wire62 is fully retracted, leaving the tubularvascular graft270 positioned as essentially illustrated in FIG. 31. It has been found that once the tubular vascular graft is firmly contiguous with the adjacent arterial wall surface, a measure of friction exists which both prevents radial collapse and axial displacement of the vascular graft within the artery. In addition, the treated arterial surface tends to weep slightly which weeping adheres to the exterior surface of the tubular graft and tends to infiltrate the material from which the tubular graft is formed at least to a limited extent further causing the graft to be retained in its expanded stationary position, fully dilated within the artery.
• As best illustrated in FIG. 32, it is presently preferred that only the[0119]proximal end269 of thevascular graft270 be physically connected to the adjacent arterial wall, in this case adventitialayer104, and that thedistal end268 be left to natural adherence, with the arterial blood pressure holding thedistal end268 in its fully dilated position together with friction at thesurface106 and tissue infiltration into the material from which thegraft270 is fabricated. In FIG. 32 the utilization of one ormore sutures304 is illustrated as the structure by which theproximal end269 of thevascular graft270 is physically secured to the arterial wall.
• Over the longer term, the graft will be held open and contiguous with the remaining original wall of the artery throughout its length by arterial blood pressure and, in grafts so constructed, by tissue in-growth into the tissue in-growth material. This particular feature of intra-luminal graft placement solves a specific problem of by-pass graft placement where by-pass grafts have previously been placed in tissue tunnels constructed to by-pass the original duct or vessel lumen. Many such grafts are placed in body regions where, under normal activities, the body tends to compress grafts and thereby cut off flow through such grafts when they are placed in tissue tunnels which by-pass the original lumen. The example of the human knee joint is illustrated in FIG. 10. Convention placement of by-pass grafts, which pass through the knee joint, results in the surrounding tissue tending to compress the graft and cut off flow when the knee is bent. Conventionally, this problem has been solved by using a reinforced graft, as previously illustrated in FIGS. 18 and 19, wherein the reinforcing holds the graft lumen open and patent when external tissue pressure is exerted on the graft.[0120]
• An improved result is obtained using the intra-luminal graft placement described herein is illustrated in FIG. 10. The original artery lumen remains open and patent in the knee even when the knee is bent. More generally, ducts and vessels naturally remain open and patent during the normal range of activities. In FIG. 10, the lumen of the graft, which is adhering to the remaining original wall of the artery by tissue in-growth and/or due to the arterial pressure inside the graft, is illustrated as remaining open and patent even while the knee is bent. More generally, intra-luminal grafts held in place in vessels or ducts by tissue in-growth will remain open and patent during the normal range of activities, including activities that tend to obstruct bypass grafts placed in tissue tunnels.[0121]
• While it is currently preferred that the[0122]distal end268 of thevascular graft270 be without manmade connection to the vascular wall, if desired thedistal end268 may be so secured. Specifically, FIG. 36 illustrates utilization of one ormore sutures304 to secure both the proximal anddistal ends269 and268, respectively, of thevascular graft270 to thearterial wall104. Placement ofsutures304 at thedistal end268 of thevascular graft270 would ordinarily require a second, downstream arteriotomy.
• Similarly, one or both ends of the[0123]vascular graft270 may be secured to thearterial wall104 usingmedical grade staples306, as illustrated in FIG. 37.
• Furthermore, either or both ends of the[0124]vascular graft270 can be expanded and held in contiguous relationship witharterial surface106 using one ormore stents226, as explained above and as illustrated in FIG. 38.
• While ordinarily not necessary, the[0125]distal end268 of thevascular graft270 may be grasped usingsuitable forceps310 for both positioning thevascular graft270 and for holding it in position while, for example, the proximal end of the graft is suitably fastened to the arterial wall as explained above. See FIG. 33.
• The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.[0126]

Claims (104)

What is claimed and desired to be secured by Letters Patent is:

1. A method of restoring reduced or absent blood flow capacity to an artery in a patient, comprising the steps of:

excavating plaque and the like from within a segment of an artery;

placing a vascular graft at a location within and as an internal lining for the artery at least co-extensive with the excavated segment;

securing the vascular graft within said artery at said location.

2. A method according toclaim 1 comprising the step of surgically accessing the artery prior to the excavating step.

3. A method according toclaim 2 comprising the step of surgically closing the artery access following the securing step.

4. A method according toclaim 2 wherein the accessing step comprises performing an arteriotomy.

5. A method according toclaim 2 wherein the accessing step comprises percutaneously using a needle.

6. A method according toclaim 1 wherein the excavating step comprises passing a guide wire through the segment of the artery.

7. A method according toclaim 6 wherein the passing step comprises advancing a dynamic wire guide into the plaque region to assist passage of the guide wire.

8. A method according toclaim 1 wherein the excavating step comprises initially loosening the plaque from artery.

9. A method according toclaim 8 wherein the loosening step comprises engaging the plaque with a dynamic disrupter.

10. A method according toclaim 8 wherein the loosening step comprises using a dynamic wire guide.

11. A method according toclaim 1 wherein the excavating step comprises performing an endarterectomy.

12. A method according toclaim 11 wherein the performing step comprises using an endarterotome.

13. A method according toclaim 11 wherein the performing step comprises using an atherotome.

14. A method according toclaim 11 wherein the performing step comprises using a Hall loop.

15. A method according toclaim 11 wherein the performing step comprises using a ring dissector.

16. A method according toclaim 11 wherein the performing step comprises using a Scanlan Endarsector.

17. A method according toclaim 11 wherein the performing step comprises using an arterial stripper.

18. A method according toclaim 2 wherein the excavating step comprises separating pieces of atheromatous and arterial material from other arterial material along an interface of weakness and pulling the pieces from the artery through the site of surgical access.

19. A method according toclaim 18 wherein the separating step comprises grasping at least one piece of atheromatous and arterial material and pulling thereon causing the piece to separate from the artery along a natural interface of weakness.

20. A method according toclaim 18 wherein the separating step comprises bluntly dissecting along the natural interface of weakness.

21. A method according toclaim 1 wherein the excavating step comprises performing an atherectomy.

22. A method according toclaim 21 wherein the performing step comprises using an atherotome.

23. A method according toclaim 21 wherein the performing step comprises using a Hall loop.

24. A method according toclaim 21 wherein the performing step comprises using a ring dissector.

25. A method according toclaim 21 wherein the performing step comprises using a Scanlan Endarsector.

26. A method according toclaim 21 wherein the performing step comprises using an arterial stripper.

27. A method according toclaim 1 wherein the excavating step comprises performing balloon angioplasty.

28. A method according toclaim 1 wherein the excavating step comprises performing laser atherectomy or angioplasty.

29. A method according toclaim 1 wherein the excavating step comprises performing ultrasound angioplasty.

30. A method according toclaim 1 wherein the excavating step comprises dilating the artery with a vessel dilator.

31. A method according toclaim 2 wherein the placing step comprises displacing the vascular graft through the surgical access site.

32. A method according toclaim 31 wherein the displacing step comprises using a forceps to grasp a distal end of the vascular graft.

33. A method according toclaim 1 wherein the placing step comprises using a balloon catheter to hold a distal end of the vascular graft by inflating the balloon inside the distal end of the vascular graft.

34. A method according toclaim 1 wherein the placing step comprises suturing a distal end of the vascular graft to a mandrel, advancing the mandrel and the vascular graft collectively into the artery, unsuturing the vascular graft from the mandrel and removing the mandrel from the artery.

35. A method according toclaim 1 wherein the placing step comprises holding the distal end of the vascular graft using a placer\suturer, pushing the vascular graft and placer\suturer concurrently into the artery, connecting the distal end of the vascular graft to the artery and removing the placer\suturer.

36. A method according toclaim 35 wherein the connecting step comprises suturing.

37. A method according toclaim 35 wherein the connecting step comprises stapling.

38. A method according toclaim 1 wherein the placing step comprises connecting a distal end of the vascular graft, a stent and a distal end of a catheter and jointly advancing the vascular graft, the stent and the catheter into the artery.

39. A method according toclaim 1 wherein the placing step comprises advancing a stent into the artery.

40. A method according toclaim 1 wherein the placing step comprises applying a coating to the excavated arterial segment.

41. A method according toclaim 1 wherein the placing step comprises inserting a sheath into the artery, advancing the vascular graft through the sheath into the artery and removing the sheath from the artery.

42. A method according toclaim 1 wherein the placing step comprises radially expanding the vascular graft while at the excavated segment of the artery.

43. A method according toclaim 42 wherein the expanding step comprises expanding a balloon inside the graft one or more times.

44. A method according toclaim 42 wherein the expanding step comprises mechanically spreading the vascular graft.

45. A method according toclaim 1 wherein the securing step comprises attaching the vascular graft to the artery by suturing.

46. A method according toclaim 1 wherein the securing step comprises attaching the vascular graft to the artery by suturing only at a proximal end of the vascular graft, leaving the distal end of the vascular graft unattached but dilated at least in part by arterial pressure.

47. A method according toclaim 1 wherein the securing step comprises attaching the vascular graft to the artery by suturing only at a proximal end of the vascular graft and by tissue in-growth, accomplished over a protracted period of time throughout the length including a distal end of the vascular graft.

48. A method according toclaim 1 wherein the securing step comprises attaching the vascular graft to the artery by stapling.

49. A method according toclaim 1 wherein the securing step comprises only attaching the vascular graft to the artery by stapling the proximal end of the vascular graft to the artery.

50. A method according toclaim 1 wherein the securing step comprises holding the vascular graft in the arterial segment by expa ndi ng at least one stent inside the vascular graft.

51. A method according toclaim 1 wherein the securing step comprises holding the vascular graft in the arterial segment by expanding at least one stent within a proximal portion of the vascular graft only.

52. A method according toclaim 1 wherein the securing step comprises independently placing the vascular graft and at least one stent within the arterial segment followed by expanding the stent inside the vascular graft.

53. A method according toclaim 1 wherein the securing step comprises connecting at least one unexpanded stent to the vascular graft, jointly inserting the connected stent and vascular graft into the artery followed by expanding the stent in respect to the vascular graft.

54. A method according toclaim 1 wherein the securing step comprises suturing the vascular graft to the artery at both proximal and distal ends thereof, access f or suturing being via spaced arteriotomies.

55. A method according toclaim 1 wherein the securing step comprises stapling the vascular graft to the artery at both proximal and distal ends thereof, access for stapling being via spaced arteriotomies.

56. A method according toclaim 1 wherein the securing step comprises suturing one end of the vascular graft to the artery and holding the other end of the vascular graft against the artery by expanding an internal stent.

57. A method according toclaim 56 wherein suturing takes place at the proximal end of the vascular graft.

58. A method according toclaim 1 wherein the securing step comprises stapling one end of the vascular graft to the artery and holding the other end of the vascular graft against the artery by expanding an internal stent.

59. A method according toclaim 58 wherein stapling takes place at the proximal end of the vascular graft.

60. A method according toclaim 1 wherein the securing step comprises expanding a stent within the vascular graft at each of the proximal and distal ends of the vascular graft.

61. A method according toclaim 60 wherein the vascular graft and the stents are separately advanced into the artery.

62. A method according toclaim 60 wherein the vascular graft and the stents are connected and then advanced into the artery.

63. A method according toclaim 62 wherein the stents are connected to the outside of the vascular graft.

64. A method of restoring lost blood flow capacity to an artery of a medical patient, comprising the steps of:

enlarging the flow path size of a plaque-ridden segment of an artery;

placing a vascular lining within the artery at least in part co-extensive with a portion of the segment;

securing the vascular graft within said artery at said location.

65. A method according toclaim 64 wherein the enlarging step comprises expanding the flow path within the artery by performing an angioplasty.

66. A method according toclaim 64 wherein the enlarging step comprises loosening plaque.

67. A method according toclaim 64 wherein the enlarging step comprises cutting plaque.

68. A method according toclaim 64 wherein the enlarging F step comprises chipping plaque.

69. A method according toclaim 64 wherein the enlarging step comprises grinding plaque.

70. A method according toclaim 64 wherein the enlarging step comprises applying laser energy to the plaque.

71. A method according toclaim 64 wherein the enlarging step comprises separating and removing both plaque and a portion of the interior of the artery.

72. A method according toclaim 64 wherein the enlarging step comprises applying ultrasound energy to the plaque.

73. A method according toclaim 64 wherein the enlarging step comprises excising pieces of plaque from the artery.

74. A method according toclaim 62 wherein the enlarging step comprises grasping and tearing pieces of plaque from the artery.

75. A method according toclaim 62 wherein the enlarging step comprises diametrally expanding the plaque-ridden segment of the artery.

76. A method of lining a vessel of a medical patient to alleviate reduced blood flow, comprising the steps of:

introducing a vascular graft material into the interior of a vessel;

placing the vascular graft material within the vessel at a predetermined arterial site;

causing adherence between the vascular graft material and the vessel at the site.

77. A method according toclaim 76 wherein the introducing step comprises advancing the vascular graft material through an incision.

78. A method according toclaim 76 wherein the placing step comprises coating the vessel with the vascular graft material.

79. A method according toclaim 77 further comprising surgically closing the incision after the causing step.

80. A method of lining a vessel of a medical patient, comprising the steps of:

enlarging the flow path size of a segment of a vessel;

placing a vascular lining at a location within the vessel at the segment;

securing the vascular lining to the inside of the vessel at said location.

81. A method of lining a vessel of a medical patient, comprising the steps of:

treating the flow path interior of a vessel;

placing a vascular lining at a location within the vessel at the segment;

securing the vascular graft to the inside of the vessel at said location.

82. A vascular graft disposed in a vessel comprising a generally cylindrically-shaped hollow member comprising an outside surface contiguous with the vessel, an inside surface defining a stenosis-resistant blood flow path lumen and at least one adherence site securing the cylindrically-shaped hollow member to the vessel.

83. A vascular graft according toclaim 82 wherein the outside surface of the generally cylindrically-shaped member is contiguous with the adventitia layer of an artery.

84. A vascular graft according toclaim 82 wherein the adherence site comprises at least one physical connection extending only through a proximal end of the generally cylindrically-shaped member into the vessel.

85. A vascular graft according toclaim 84 wherein the physical connections extend through both the proximal end and a distal end of the generally cylindrically-shaped member into the vessel.

86. A vascular graft according toclaim 82 further comprising at least one expanded stent disposed within the generally cylindrically-shaped member biasing the cylindrically-shaped member against the vessel.

87. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises a coating.

88. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises a tubular synthetic resinous member.

89. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises shape-retaining internal reinforcement.

90. A vascular graft according toclaim 89 wherein the tubular synthetic resinous member comprises a biologically inert fabric and a stiff, high density material.

91. A vascular graft according toclaim 88 wherein the tubular synthetic resinous member comprises a soft, low density material.

92. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises an annulus having a uniform inside bore.

93. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member is tapered.

94. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member is bifurcated.

95. A vascular graft according toclaim 89 wherein the reinforcement comprises at least one ring.

96. A vascular graft according toclaim 89 wherein the reinforcement comprises a spirally-shaped member.

97. A vascular graft according toclaim 82 further comprising at least one expandable stent connected to the generally cylindrically-shaped member.

98. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises at least in part a lumen taken from a human being.

99. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises at least in part a lumen taken from an animal.

100. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises tissue in-growth receiving material.

101. A vascular graft according toclaim 82 wherein the generally cylindrically-shaped member comprises a material diametrally expanded while in the vessel.

102. A vascular graft according toclaim 100 wherein the adherence runs the full length of the graft due to tissue in-growth.

103. A vascular graft according toclaim 102 wherein the blood flow path lumen inside the graft remains open and patent in all situations where the original vessel lumen would normally remain open and patent.

104. A vascular graft according toclaim 103 wherein the situations include situations that would tend to occlude vascular grafts placed in by-pass tissue tunnels.

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