United States Patent [19J
`Limon et al.
`
`[54] SELF-EXPANDING STENT DELIVERY
`SYSTEM
`
`[75]
`
`Inventors: Timothy A. Limon, Cupertino;
`Richard J. Saunders, Redwood City,
`both of Calif.
`
`[73] Assignee: Advanced Cardiovascular Systems,
`Inc., Santa Clara, Calif.
`
`[ *] Notice:
`
`This patent issued on a continued pros(cid:173)
`ecution application filed under 37 CFR
`1.53( d), and is subject to the twenty year
`patent term provisions of 35 U.S.C.
`154(a)(2).
`
`[21] Appl. No.: 08/680,429
`
`[22] Filed:
`
`Jul. 15, 1996
`
`Int. Cl.7 ........................................................ A61F 2/06
`[51]
`[52] U.S. Cl. ................................ 623/1; 606/108; 606/192
`[58] Field of Search ....................... 606/1, 108, 191-200;
`623/1, 11, 12
`
`[56]
`
`References Cited
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`I 1111111111111111 11111 1111111111 111111111111111 IIIII IIIII lll111111111111111
`US006077295A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,077,295
`*Jun.20,2000
`
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`
`(List continued on next page.)
`
`FOREIGN PATENT DOCUMENTS
`
`5/1994 Canada.
`2102019
`8/1993 European Pat. Off ..
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`5/1994 European Pat. Off ..
`0 596 145
`9/1990 Germany.
`90 10 130 U
`WO 95/33422 12/1995 WIPO.
`WO 96/39998 12/1996 WIPO.
`
`Primary Examiner-Glenn K. Dawson
`Attorney, Agent, or Firm-Fulwider Patton Lee & Utecht,
`LLP
`
`[57]
`
`ABSTRACT
`
`A stent-delivery catheter system delivers and implants a
`self-expanding stent intraluminally into a human patient's
`body lumen. A self-expanding stent is removabaly attached
`to the distal end of an inner member so that attachment
`projections prevent axial movement of the stent on the inner
`member while the stent is being delivered and implanted in
`a patient's body lumen.
`
`13 Claims, 6 Drawing Sheets
`
`55
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 1 of 14
`
`

`

`6,077,295
`Page 2
`
`U.S. PATENT DOCUMENTS
`
`3/1993 Hull.
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`
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`9/1996 Das.
`5,690,643 11/1997 Wijay ...................................... 606/108
`5,935,135
`8/1999 Bramlitt et al.
`........................ 606/108
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 2 of 14
`
`

`

`U.S. Patent
`
`Jun.20,2000
`
`Sheet 1 of 6
`
`6,077,295
`
`}
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 3 of 14
`
`

`

`U.S. Patent
`
`Jun.20,2000
`
`Sheet 2 of 6
`
`6,077,295
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 4 of 14
`
`

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`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 5 of 14
`
`

`

`U.S. Patent
`
`Jun.20,2000
`
`Sheet 4 of 6
`
`6,077,295
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 6 of 14
`
`

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`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 7 of 14
`
`

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`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 8 of 14
`
`

`

`6,077,295
`
`1
`SELF-EXPANDING STENT DELIVERY
`SYSTEM
`
`BACKGROUND OF THE INVENTION
`
`2
`vasculature, the present invention provides means for
`removably attaching the stent to the catheter so that it cannot
`move axially on the catheter shaft.
`A catheter assembly for removably attaching an intravas-
`5 cular stent is provided in which an elongated catheter has an
`inner member and an outer member extending along a
`longitudinal axis wherein the inner member and the outer
`member have a coaxial configuration and are dimensioned
`for relative axial movement. A self-expanding stent, having
`10 an open lattice structure, and being biased toward an open
`configuration, is mounted within the outer member. The
`inner member is slidably positioned within the lumen of the
`stent, and then the inner member is heated until it conforms
`and fills the open lattice structure of the stent with attach-
`15 ment projections.
`The present invention includes an inner member that is
`naturally pliable and deformable or is heat-deformable and
`formed from a polymeric material which when heated will
`fill the open lattice structure of the stent with attachment
`projections. The inner member can be formed from poly(cid:173)
`meric materials including polyurethanes, polyethylenes,
`polyethylterpthalate, and nylons.
`In another embodiment of the invention, an elastomeric
`sleeve is attached to the distal end of the inner member. This
`25 stent is mounted in the distal end of the outer member and
`is biased outwardly against the outer member. The inner
`member distal end and its sleeve are positioned within the
`stent, and the sleeve is heated until it fills and forms
`attachment projections in the open lattice structure of the
`stent.
`The invention also relates to the method of mounting the
`self-expanding stent on the delivery catheter. The delivery
`catheter includes an outer member and an inner member
`having relative axial movement and control handles for
`providing relative axial movement between the members.
`The self-expanding stent is positioned within the inner
`lumen of the outer member and the control handles are
`manipulated to slide the inner member distal end within the
`inner lumen of the self-expanding stent. Thereafter, heat is
`applied to the inner member distal end so that it conforms
`and fills the open lattice structure of the self-expanding stent
`with attachment projections, thereby removably attaching
`the self-expanding stent to the inner member distal end and
`45 preventing axial movement of the stent. The self-expanding
`stent remains biased radially outwardly and is retained from
`expanding by the outer member.
`The invention also includes a method of implanting a
`self-expanding stent utilizing the catheter-delivery system
`described above. Using the catheter-delivery system, the
`stent is advanced through a patient's vascular system until it
`is positioned at the site where the stent is to be implanted.
`The control handles are manipulated to simultaneously
`move the inner member axially in a distal direction and the
`55 outer member axially in a proximal direction. As the stent is
`exposed and no longer retained by the outer member, it will
`deploy by self-expanding radially outwardly into contact
`with the body lumen. The stent will not move axially on the
`catheter shaft as the inner member and the outer member are
`60 moved axially relative to one another, since the stent is
`removably attached to the inner member by attachment
`projections. After the stent is deployed, the catheter-delivery
`system is withdrawn from the patient.
`One feature of the present invention is to permit the
`physician to partially deploy the stent, and if it is improperly
`positioned, the outer member can be moved axially to
`recapture the partially deployed stent so that the stent can be
`
`The invention relates to self-expanding stent delivery
`systems, which are used to implant a stent into a patient's
`body lumen to maintain the patency thereof. The stent
`delivery system is useful in the treatment and repair of body
`lumens, including coronary arteries, renal arteries, carotid
`arteries, and other body lumens.
`Stents are generally cylindrically-shaped devices which
`function to hold open and sometimes expand a segment of
`a blood vessel or other body lumen. They are particularly
`suitable for use to support and hold back a dissected arterial
`lining which can occlude the fluid passageway therethrough.
`Stents also are useful in maintaining the patency of a body
`lumen, such as a coronary artery, after a percutaneous
`transluminal coronary angioplasty (PTCA) procedure or an
`atherectomy procedure to open a stenosed area of the artery. 20
`A variety of devices are known in the art for use as stents
`and have included coiled wires in a variety of patterns that
`are expanded after being placed intraluminally by a balloon
`catheter; helically wound coil springs manufactured from an
`expandable heat sensitive material such as nickel-titanium;
`and self-expanding stents inserted in a compressed state and
`shaped in a zig-zag pattern.
`Typically, the aforementioned stents are delivered intralu(cid:173)
`minally through a percutaneous incision through the femoral
`or renal arteries. A stent is mounted on the distal end of an
`elongated catheter, typically on the balloon portion of a
`catheter, and the catheter and stent are advanced intralumi(cid:173)
`nally to the site where the stent is to be implanted. Typically
`with expandable stents, the balloon portion of the catheter is
`inflated to expand the stent radially outwardly into contact 35
`with the arterial wall, whereupon the stent undergoes plastic
`deformation and remains in an expanded state to hold open
`and support the artery.
`With respect to self-expanding stents, typically a retrac(cid:173)
`tably sheath is positioned over the self-expanding stent 40
`which is mounted on the distal end of the catheter. Once the
`catheter has been advanced intraluminally to the site where
`the stent is to be implanted, the sheath is withdrawn thereby
`allowing the self-expanding stent to expand radially out(cid:173)
`wardly into contact with the arterial wall, thereby holding
`open and supporting the artery.
`One of the problems associated with the prior art stents
`and catheter-delivery systems, is to removably attach the
`stent to the catheter's distal end or the balloon portion of the
`catheter so that the stent does not dislodge or move axially
`on the catheter or balloon.
`What has been needed and heretofore unavailable is a
`reliable catheter-delivery system on which the stent can be
`mounted and removably attached so that it does not move
`axially on the catheter either during delivery and advance(cid:173)
`ment through the vascular system, or during implanting of
`the stent. The present invention satisfies this need.
`
`50
`
`30
`
`SUMMARY OF THE INVENTION
`
`The present invention is directed to a self-expanding stent
`delivery system in which a self-expanding stent is remov(cid:173)
`ably attached to a catheter so that the stent remains in
`position on the catheter until it is implanted. Unlike prior art
`stents, which may have a tendency to dislodge or move 65
`axially on the catheter shaft when the sheath is withdrawn or
`when the catheter is advanced through a tortuous
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 9 of 14
`
`

`

`6,077,295
`
`3
`repositioned in the proper location. For example, the control
`handles can be manipulated to simultaneously move the
`inner member axially in the distal direction and the outer
`member axially in a proximal direction to begin to deploy
`the stent. Thereafter, if it is determined that the stent is being 5
`implanted at the wrong location in an artery, the control
`handles can be manipulated to simultaneously move the
`inner member axially in a proximal direction and the outer
`member axially in a distal direction to recapture the partially
`deployed stent so that it can be repositioned in the proper 10
`location in the artery. The stent is then implanted as
`described above.
`Other features and advantages of the present invention
`will become more apparent from the following detailed
`description of the invention, when taken in conjunction with
`the accompanying exemplary drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIGS. 1-4 represent elevational views of prior art stents
`and catheter-delivery systems where the stents are self(cid:173)
`expanding either because they are biased radially outwardly
`or formed from a heat sensitive material such as nickel(cid:173)
`titanium.
`FIG. 5 is a schematic view of the catheter-delivery system
`of the invention having the self-expanding stent positioned
`within the inner lumen of the outer member before the stent
`is mounted on the inner member.
`FIG. SA is a cross section of FIG. 5 along line 5A-5A.
`FIG. 6 is a schematic view depicting the inner member
`positioned within the inner lumen of the self-expanding
`stent, and a tapered mandril inserted in the inner member for
`the purpose of applying heat to form attachment projections.
`FIG. 7 is a schematic view depicting an alternative
`embodiment of the invention in which an elastomeric seg(cid:173)
`ment is positioned on the distal end of the inner member and
`is used to conform and fill in the open lattice structure of the
`self-expanding stent with attachment projections.
`FIG. 8 is a schematic view of an over-the-wire catheter-
`delivery system in which the stent is being positioned at a 40
`narrowed portion of the vessel wall.
`FIG. 9 is a schematic view depicting the over-the-wire
`catheter-delivery system of FIG. 8 in which the outer
`member is being withdrawn proximally so that the stent can
`self-expand radially outwardly into contact with the vessel
`wall.
`FIG. 10 is a schematic view depicting the stent of FIGS.
`8 and 9 being implanted and contacting the vessel wall.
`FIG. 11 is a schematic view depicting a rapid-exchange
`catheter-delivery system in which the guide wire extends
`through a port in the side of catheter so that the catheter may
`be rapidly exchanged upon withdrawal from the patient.
`FIG. 12 is a schematic view depicting the catheter(cid:173)
`delivery system of FIG. 11 in which the stent is self(cid:173)
`expanding as the outer member is withdrawn axially in the
`proximal direction.
`FIG. 13 is a schematic view depicting the rapid-exchange
`catheter-delivery system in which the self-expanding stent
`has been implanted into contact with the vessel wall, and the 60
`rapid-exchange catheter is ready to be withdrawn from the
`patient's vascular system.
`
`4
`minally into a human patient's body lumen, such as a
`coronary artery, carotid artery, renal arteries, peripheral
`arteries and veins, and the like. The invention provides for
`a stent delivery catheter assembly and its method of use in
`which a stent is implanted in a patient.
`As can be seen in FIGS. 1-4, there are numerous prior art
`stents which are adapted for use with the present invention.
`The stents depicted in FIGS. 1-4 are all self-expanding
`stents and will expand from a contracted condition where
`they are mounted on the catheter assembly, to an expanded
`condition where the stent comes in contact with the body
`lumen. The stents are self-expanding, which can be achieved
`by several means. As depicted in FIGS. 1-4, the prior art
`stents are formed from a stainless steel material and are
`configured so that they are biased radially outwardly and
`15 they will expand outwardly unless restrained. The stents
`depicted in FIGS. 1-4 also can be formed from a heat
`sensitive material, such as nickel titanium, which will self(cid:173)
`expand radially outwardly upon application of a transfor(cid:173)
`mation temperature. These prior art stents are representative
`20 of a large number of stents which can be adapted for use with
`the present invention.
`In a preferred embodiment of the invention, as depicted in
`FIGS. 5, SA and 6, catheter assembly 20 is provided to
`deliver and implant a stent. Catheter assembly 20 incorpo-
`25 rates elongated catheter body 21 which has proximal end 22
`and distal end 23. An inner member 24 and an outer member
`25 are arranged in coaxial alignment. Inner member 24 is
`slidably positioned within outer member 25 and relative
`axial movement between the two members is provided by
`30 inner member control handle 26 and outer member control
`handle 27. The control handles 26,27 can take numerous
`forms, but are depicted schematically for ease of illustration.
`As an example, however, control handles 26, 27 can take the
`form of a thumb-switch arrangement, a rotating-screw-type
`35 arrangement, or a ratcheting arrangement. Such control
`handle means are well known in prior art catheter-delivery
`systems.
`A self-expanding stent 28 having an open lattice structure
`29 is mounted on the distal end 23 of catheter assembly 20.
`Self-expanding stent 28 can take virtually any configuration
`that has an open lattice structure 29, as can be seen in the
`examples of the prior art stents shown in FIGS. 1-4.
`In keeping with the invention, the self-expanding stent 28
`is inserted in outer member inner lumen 31 and positioned
`45 at the outer member distal end. In those instances where
`self-expanding stent 28 is made from stainless steel or a
`similar material that is biased outwardly, stent 28 will be
`compressed and inserted into inner lumen 31. Thereafter,
`inner member distal end 32 is positioned within stent inner
`50 lumen 34 so that the inner member outer surface 33 can
`come into contact with the stent inner lumen 34.
`In keeping with the preferred embodiment, inner member
`distal end 32 is made from a polymeric material that either
`is soft by design, or will become soft when heat is applied.
`55 The intent is to removably attach self-expanding stent 28 on
`outer surface 33 of inner member 24. Outer surface 33 will
`partially fill the open lattice structure 29 of stent 28 to form
`attachment projections 30 so that the stent cannot move in an
`axial direction along outer surface 33 of inner member 24.
`In the preferred embodiment, self-expanding stent 28 is
`mounted on outer surface 33 at the inner member distal end
`32 and the open lattice structure 29 is filled by attachment
`projections 30. Due to the coaxial arrangement between
`inner member 24 and outer member 25, the inner lumen 31
`65 of outer member 25 covers self-expanding stent 28 and helps
`to retain the stent on the outer surface 33 of the inner
`member 24.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`The present invention relates to a stent delivery catheter
`system in which a self-expanding stent is delivered intralu-
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 10 of 14
`
`

`

`6,077,295
`
`10
`
`5
`In order to conform outer surface 33 so that it conforms
`or fills the open lattice structure 29 of the self-expanding
`stent with attachment projections 30, heat can be applied by
`various methods. For example, a tapered mandrill 35, as
`depicted in FIG. 6, is inserted in inner member distal end 32
`in region of the stent. Heat is then applied to outer member
`25 by known means, such as by using a heated capture tube
`(not shown) surrounding outer member 25. The capture tube
`can be formed from teflon, glass, or the like and generally is
`warmed by using heated air. As outer member warms, inner
`member 33 is inserted within inner lumen 31 of outer
`member 25 allowing attachment projections 30 to flow and
`form around stent 28.
`In another preferred embodiment, as depicted in FIG. 7,
`an elastomeric segment 40 is attached on outer surface 33 at
`the distal end 32 of the inner member. Elastomeric segment
`40 is formed from a heat sensitive material, or is designed
`to be relatively soft as compared to inner member 24, such
`that stent 28 can be removably attached on elastomeric
`segment 40, which will conform and fill in open lattice 20
`structure 29 of the stent with attachment projections 30. The
`elastomeric segment can be heated by the aforementioned
`methods, or if it is formed of a material that is relatively soft,
`it will naturally conform and fill in open lattice structure 29
`with attachment projections 30 without the application of 25
`heat.
`In the preferred method of use, catheter assembly 20 is
`used to implant the self-expanding stent in a body lumen
`using an over-the-wire or rapid-exchange catheter configu(cid:173)
`ration. In one preferred embodiment, as depicted in FIGS.
`8-10, over-the-wire catheter 50 has a guide wire lumen 51
`which extends through the catheter and is configured to
`receive guide wire 52. In order to implant self-expanding
`stent 28, guide wire 52 is positioned in a patient's body
`lumen, at vessel wall 55, and typically guide wire 52 extends
`past a stenosed region 56. Distal end 54 of over-the-wire
`catheter 50 is threaded over the proximal end of the guide
`wire which is outside the patient (not shown) and catheter 50
`is advanced along the guide wire until distal end 54 of
`catheter 50 is positioned within stenosed region 56.
`As depicted in FIGS. 9 and 10, self-expanding stent 28 is
`implanted in stenosed region 56 by moving outer member 25
`in a proximal direction while simultaneously moving inner
`member 24 in a distal direction. The stent 28 will not slide
`or move axially on outer surface 33 since the open lattice
`structure is filled in with attachment projections 30. As
`portions of self-expanding stent 28 are no longer contained
`by outer member 24, it will expand radially outwardly into
`contact with vessel wall 55 in the area of stenosed region 56.
`When fully deployed and implanted, as shown in FIG. 10,
`stent 28 will support and hold open stenosed region 56 so
`that blood flow is not restricted. Attachment projections 30
`do not inhibit the stent 28 from self-expanding radially
`outwardly, they only impede axial movement of the stent.
`With certain self-expanding stents, there is a tendency of
`the stent to shorten somewhat when it expands. When stent
`shortening occurs, the physician may find that the stent has
`been improperly placed in the stenosed region 56 if the
`effects of shortening have not been taken into consideration.
`Accordingly, it may be necessary, as described above, to
`move inner member 24 distally in order to compensate for
`stent shortening upon expansion of the stent. It is also
`possible due to stent design, that the self-expanding stent
`will not appreciably shorten upon expansion. If this is the
`case, it may be unnecessary to move inner member 24 65
`distally while simultaneously moving outer member 25
`proximally in order to release self-expanding stent 28 in the
`
`6
`body lumen. With a stent configuration that does not appre(cid:173)
`ciably shorten during expansion, outer member 25 is moved
`axially while inner member 24 remains stationary as self(cid:173)
`expanding stent 28 expands radially outwardly into contact
`5 with vessel wall 55. After stent 28 is implanted and contacts
`stenosed region 56, over-the-wire catheter 50 is withdrawn
`from the patient's vascular system. A typical over-the-wire
`catheter design is disclosed in U.S. Pat. No. Bl 4,323,071,
`which is incorporated herein by reference.
`In another preferred method of implanting a stent, as
`depicted in FIGS. 11-13, rapid-exchange catheter 60 is
`provided. Rapid-exchange catheters are known in the art and
`details of the construction and use are set forth in U.S. Pat.
`Nos. 5,458,613; 5,346,505; and 5,300,085, which are incor-
`15 porated herein by reference. Generally, rapid-exchange cath(cid:173)
`eters include guide wire lumen 61 which extends in the distal
`portion of the catheter from side port 63 to the distal end of
`the catheter. Guide wire 62 is inserted through guide port 63
`and extends out the distal end of catheter 60 so that the distal
`end of the guide wire is positioned beyond stenosed region
`56. The method of deploying self-expanding stent 28 using
`rapid-exchange catheter 60 is similar to that described for
`using over-the-wire catheter 50. One of the differences
`between the catheter-delivery systems includes slit 64 in
`rapid-exchange catheter 60 which extends from side port 63
`to approximately just proximal of the area where stent 28 is
`mounted. After stent 28 is implanted in stenosed region 56,
`rapid-exchange catheter 60 is withdrawn from the patient's
`vascular system and guide wire 62 will peel through slit 64
`30 making the exchange of one catheter for another a simple
`process. Typically, stiffening mandrill 65 is incorporated in
`the proximal region of rapid-exchange catheter 60 to
`enhance the pushability of the catheter through the patient's
`vascular system, and to improve the trackability of the
`35 catheter over the guide wire.
`The stents as described herein can be formed from any
`number of materials, including metals, metal alloys and
`polymeric materials. Preferably, the stents are formed from
`metal alloys such as stainless steel, tantalum, or the so-called
`40 heat sensitive metal alloys such as nickel titanium (NiTi).
`Stents formed from stainless steel or similar alloys typically
`are designed, such as in a helical coil or the like, so that they
`are spring biased outwardly.
`With respect to stents formed from shape-memory alloys
`45 such as NiTi (nickel-titanium alloy), the stent will remain
`passive in its martensitic state when it is kept at a tempera(cid:173)
`ture below the transition temperature. In this case, the
`transition temperature will be below normal body
`temperature, or about 98.6° F. When the NiTi stent is
`50 exposed to normal body temperature, it will immediately
`attempt to return to its austenitic state, and will rapidly
`expand radially outwardly to achieve its preformed state.
`Details relating to the properties of devices made from
`nickel-titanium can be found in "Shape-Memory Alloys,"
`55 Scientific American, Vol. 281, pages 74-82 (November
`1979), which is incorporated herein by reference.
`With respect to all of the embodiments disclosed above,
`inner member 24, and for that matter outer member 25, can
`be formed from polymeric materials including
`60 polyurethanes, polyethylenes, polyethylterpthalate, and
`nylons. Similarly, elastomeric segment 40 can be formed
`from polyurethane, elastomeric polyesters and the like.
`Generally speaking, the more proximal portions of inner
`member 24 and outer member 25 will be formed of a
`polymeric material that is stiffer than the distal section so
`that the proximal section has sufficient pushability to
`advance through the patient's vascular system. On the other
`
`Edwards Lifesciences Corporation, et al. Exhibit 1008, p. 11 of 14
`
`

`

`6,077,295
`
`15
`
`7
`hand, the more distal portion of inner member 24 and outer
`member 25 can be formed of a more flexible material so that
`the distal portion of the catheter will remain flexible and
`track more easily over the guide wire.
`Other modifications and improvements may be made 5
`without departing from the scope of the invention. For
`example, the various drawing figures depict several configu(cid:173)
`rations of the stent including various sizes, which can be
`modified to suit a particular application without departing
`from the spirit and scope of the invention. Further, the 10
`configuration of the catheter assembly is a coaxial arrange(cid:173)
`ment between the inner member and the outer member,
`which can be modified to other configurations without
`departing from the preferred invention.
`What is claimed is:
`1. A catheter assembly comprising:
`an elongated catheter having a proximal end and a distal
`end;
`the catheter having an inner member and an outer member
`extending along a longitudinal axis, the inner member 20
`and the outer member having a coaxial configuration
`and dimensioned for relative axial movement;
`means for providing relative axial movement between the
`inner member and the outer member;
`a self-expanding stent having an open lattice structure 25
`configured to be biased from a delivery configuration
`having a reduced cross section and a predetermined
`length to an open configuration with an enlarged cross
`section and being positioned within a distal end of the
`outer member in the delivery configuration; and
`a plurality of attachment projections at a distal end of the
`inner member spaced along the stent a distance at least
`as great as the predetermined length for facilitating the
`removable attachment of the stent to the inner member
`distal end.
`2. The catheter assembly of claim 1, wherein the attach(cid:173)
`ment projections are formed from a heat-deformable poly(cid:173)
`meric material at the distal end of the inner member.
`3. The catheter assembly of claim 2, wherein the poly(cid:173)
`meric material on the distal end of the inner member is taken 40
`from the group of polymeric materials including
`polyurethanes, polyethylenes, polyethylterpthalate, and
`nylons.
`4. The catheter assembly of claim 1, wherein the means
`for providing relative axial movement between the inner 45
`member and the outer member includes a control handle
`positioned at the proximal end of the elongated catheter.
`5. The catheter assembly of claim 1, wherein the self(cid:173)
`expanding stent is formed from a metal alloy taken from the
`group of metal alloys including stainless steel, nickel- 50
`titanium, and tantalum.
`6. The catheter assembly of claim 1, wherein the inner
`member of the elongated catheter has a through lumen for
`receiving a guide wire so that the elongated catheter can be
`positioned within a body lumen by advancing it over the 55
`guide wire.
`7. The catheter assembly of claim 1, wherein the inner
`member of the elongated catheter has a side port for receiv(cid:173)
`ing a guide wire, the side port being positioned so that the
`catheter can be rapidly exchanged.
`8. The catheter assembly of claim 1, wherein the distal
`end of the elongated catheter includes an elastomeric sleeve
`attached to the distal end, the elastomeric sleeve adapted to
`conform and fill the lattice structure of the self-expanding
`stent with the plurality of attachment projections.
`9. A method of mounting an intravascular stent on a
`delivery catheter, the method comprising:
`
`60
`
`65
`
`30
`
`35
`
`8
`providing a delivery catheter having an elongated catheter
`body and a proximal end and a distal end, the catheter
`having an inner member and an outer member extend(cid:173)
`ing along a longitudinal axis, the inner member and the
`outer member having a coaxial configuration and
`d