(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2003/0236567 A1
`(43) Pub. Date:
`Dec. 25, 2003
`Elliot
`
`US 20030236567A1
`
`(54)
`
`(75)
`
`(73)
`(21)
`(22)
`
`(51)
`(52)
`
`IMPLANTABLE PROSTHESIS WITH
`DISPLACEABE SKIRT
`
`Inventor: Chris Elliot, Hopkinton, MA (US)
`
`Correspondence Address:
`HOFFMANN & BARON, LLP
`6900 J ERICHO TURNPIKE
`SYOSSET, NY 11791 (US)
`
`Assignee: Scimed Life Systems, Inc.
`
`Appl. No.:
`
`10/179,535
`
`Filed:
`
`Jun. 25, 2002
`
`Publication Classi?cation
`
`Int. Cl.7 ...................................................... .. A61F 2/06
`US. Cl. .......................................... .. 623/113; 623/13
`
`(57)
`
`ABSTRACT
`
`An implantable prosthesis is provided having a radially
`eXpandable tubular body and at least one skirt extending
`therefrom. The skirt terminates in a peripheral edge, Wherein
`at least portions of the peripheral edge are free and displace
`able to a greater diameter of the tubular body. Thus, With the
`implantable prosthesis being a stent-graft used to treat an
`aortic aneurysm (e.g., abdominal aortic aneurysm
`(“AAA”)), the skirt may be used to inhibit Type I endoleaks
`upon its selective displacement in response to irregular
`aortic shaping and/or aneurysm neck expansion. The skirt
`may actively inhibit Type I endoleaks by forming a physical
`barrier against ?oW betWeen the tubular body and the aortic
`Wall. In addition, the skirt may passively inhibit endoleak
`formation by sufficiently restricting blood How to alloW
`coagulation and clot formation, Which Would act as a barrier
`against endoleakage.
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 1 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 1 0f 7
`
`US 2003/0236567 A1
`
`24
`
`RA
`
`I4
`
`73/5‘ 1
`.Pm/Z A???’
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 2 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 2 0f 7
`
`US 2003/0236567 A1
`
`2
`
`v EHHHHHUHHUHU
`
`
`
`_ a.‘ NTIIIIIIPV
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 3 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 3 of 7
`
`US 2003/0236567 Al
`
`N.
`
`10
`N
`
`22““
`“F
`
`L0
`
`:6
`
`Mad
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 4 of 13
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 4 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 4 0f 7
`
`US 2003/0236567 A1
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 5 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 5 0f 7
`
`US 2003/0236567 A1
`
`17/
`
`£1
`MU
`a,
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 6 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 6 0f 7
`
`US 2003/0236567 A1
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 7 of 13
`
`

`

`Patent Application Publication Dec. 25, 2003 Sheet 7 0f 7
`
`US 2003/0236567 A1
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 8 of 13
`
`

`

`US 2003/0236567 A1
`
`Dec. 25, 2003
`
`IMPLANTABLE PROSTHESIS WITH
`DISPLACEABE SKIRT
`
`FIELD OF THE INVENTION
`[0001] This invention relates to tubular prostheses, includ
`ing, but not limited to, endovascular grafts and stent-grafts,
`for maintaining patency of blood vessels and treating aneu
`rysms (e.g., aortic aneurysms), and tubular conduits for
`maintaining patency in other bodily passageways.
`BACKGROUND OF RELATED TECHNOLOGY
`[0002] It is knoWn in the prior art to use endovascular
`prostheses to treat aortic aneurysms (e.g., abdominal aortic
`aneurysms (“AAA”)). Such treatment includes implanting a
`stent, or stent-graft, Within the diseased vessel to by-pass the
`anomaly. An aneurysm is a sac formed by the dilation of the
`Wall of the artery, Which may be congenital, but usually is
`caused by disease and, occasionally, by trauma. With refer
`ence to FIG. 1, sac 1 of aneurysm A is de?ned by dilated
`portions 2 of aorta AA. With the collection of blood and
`other embolic material in the sac 1, and being subjected to
`hemodynamic pressure, the aneurysm A may rupture, if
`untreated, causing internal bleeding.
`[0003] Techniques had been developed in the prior art
`Where diseased portions of a blood vessel, such as With an
`aneurysm, Were ablated and replaced With a prosthetic
`member, such as that shoWn in US. Pat. No. 4,938,740 to
`Melbin. This technique, hoWever, required open surgery. As
`an improvement over this technique, endovascular emplace
`ment techniques have been developed to implant grafts and
`stent-grafts into a vessel from a remote puncture site,
`thereby obviating the need for open surgery. For example, as
`shoWn in FIG. 1, an endovascular prosthesis 3 (stent or
`stent-graft) is positioned to by-pass the aneurysm A With
`ends 4, 5 of the prosthesis being in contiguous contact With
`healthy portions of the aorta AA, the prosthesis 3 having
`been introduced endovascularly (e.g., With a catheter).
`Accordingly, if the aneurysm AWere to rupture, blood ?oW
`through the aorta AA Would be uninterrupted, and internal
`bleeding generally avoided. Aortic aneurysms Which com
`monly form betWeen the renal arteries RA and the iliac
`arteries IA are referred to as abdominal aortic aneurysms
`(“AAA”) (shoWn in FIG. 1). Other aneurysms are possible
`in the aorta, such as thoracic aortic aneurysms (“TAA”) and
`aortic uni-iliac (“AUI”) aneurysms.
`[0004] Although considerable success has been enjoyed
`With stent and stent-graft performance, failures in the form
`of endoleaks have been noted and predominantly classi?ed
`in four classes: Types I-IV. Type I failures relate to leaks
`betWeen the vascular prosthesis and the vessel Wall. For
`example, With reference to FIG. 1, a Type I failure Would be
`blood Weeping about the end 4 of the prosthesis 3 into the
`sac 1. Type I failures have been found to be caused by a
`continual expansion of the aneurysm neck (portion of the
`aorta AA extending cephalad or caudad from the aneurysm
`A). This expansion rate has been estimated to be about 1
`mm/year. With the aneurysm neck expanding beyond the
`natural resting diameter of the prosthesis 3, passageWay(s)
`are de?ned about the prosthesis 3 in communication With the
`aneurysm sac 1. Additionally, Type I endoleaks are also
`caused When circular prostheses are implanted in non
`circular aortic lumens, Which may be caused by irregular
`vessel formation and/or calci?ed topography of the lumen of
`the aorta AA.
`
`[0005] A Type II failure involves blood ?oWing into the
`aneurysm sac through collateral vessels. Again, With refer
`ence to FIG. 1, the sac 1 may be in ?uid communication
`With blood vessels BV, other than the aorta AA. Typically,
`lumbar arteries are in ?uid communication (directly or
`indirectly) With an aneurysm sac. Since blood ?oW out of the
`sac 1 is prevented, hemodynamic pressure aWay from the sac
`1 is not present. HoWever, because of hemodynamic pres
`sure Within blood vessels in communication With the sac 1,
`blood ?oW, nevertheless, is directed into the sac 1 (as shoWn
`by arroWs). A technique has been developed in the prior art
`Which calls for emboliZing the blood vessels BV, such as
`With embolus coils, thereby isolating the sac 1 from collat
`eral blood ?oW. HoWever, an additional procedure Would be
`required for emboliZation.
`
`[0006] AType III failure is a mechanical failure, Wherein
`a hole may be ripped into the prosthesis (e.g., excessive Wear
`at a metal/non-metal (fabric or polymer) interface) or poor
`integrity exists at a connection, or connections, betWeen
`modular components of a prosthesis, (e.g., extensions may
`be connected to the prosthesis to obtain improved secure
`ment in one or both of the iliac arteries IA.) For example, as
`shoWn in FIG. 1, a hole 6 may be torn into the prosthesis 2,
`or poor sealing is obtained at the connection betWeen the
`prosthesis 3 and an extension 7.
`
`[0007] A Type IV failure relates to excessive prosthesis
`porosity, Wherein blood seeps through the prosthesis regard
`less of the integrity of sealing and mechanical connections.
`
`[0008] As can be readily appreciated, even With the suc
`cessful implantation of an endovascular prosthesis, failures
`may occur thereafter. It has been found that Type I failures
`may affect up to 5-10% of all implanted prostheses. Accord
`ingly, there is a clear need for an endovascular prosthesis
`Which can reduce the likelihood of, and ideally eliminate,
`Type I failures.
`
`SUMMARY OF THE INVENTION
`
`[0009] To overcome shortcomings in the prior art, and to
`limit Type I endoleaks, an implantable prosthesis is provided
`having a radially-expandable tubular body and at least one
`skirt extending therefrom. The skirt terminates in a periph
`eral edge, Wherein at least portions of the peripheral edge are
`free and displaceable to a greater diameter than the tubular
`body. Thus, With the implantable prosthesis being a stent
`graft used to treat an aortic aneurysm (e.g., abdominal aortic
`aneurysm (“AAA”)), the skirt may be used to inhibit Type
`I endoleaks upon its selective displacement in response to
`irregular aortic shaping and/or aneurysm neck expansion.
`The skirt may actively inhibit Type I endoleaks by forming
`a physical barrier against ?oW betWeen the tubular body and
`the aortic Wall. In addition, the skirt may passively inhibit
`endoleak formation by suf?ciently restricting blood How to
`alloW coagulation and clot formation, Which Would act as a
`barrier against endoleakage. Endothelial cell ingroWth into
`the skirt may also occur providing a cellular barrier against
`endoleakage.
`[0010] The skirt may be supported by a scaffold, such as
`a plexus of elements arranged in any knoWn pattern used in
`stent manufacturing. Alternatively, the skirt may have lim
`ited support, such as by a plurality of circumferentially
`spaced tines. As a further alternative, the skirt need not be
`supported. Furthermore, the skirt may be formed to be
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 9 of 13
`
`

`

`US 2003/0236567 A1
`
`Dec. 25, 2003
`
`displaceable into various shapes, including being tapered or
`cylindrical; or, may be formed With portions of different
`geometric con?gurations, such as a ?rst portion Which
`extends circumferentially outWardly from the prosthesis,
`With a second portion that it is coextensive With the pros
`thesis. The circumferential portion may be trough-shaped
`such that force applied thereto by blood How may be
`re-directed to de?ne a radial force directed aWay from the
`prosthesis. Such an outWard radial force may be used to
`press portions of the peripheral edge against the blood vessel
`Wall in reinforcing a seal thereWith.
`
`[0011] These and other features Will be better understood
`through a study of the folloWing detailed description and
`accompanying draWings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0012] FIG. 1 is a schematic of an aortic aneurysm With
`a stent-graft implanted therein;
`[0013] FIGS. 2a and 2b shoW implantable prostheses;
`
`[0014] FIGS. 3a-3e shoW a ?rst embodiment of the sub
`ject invention;
`[0015] FIGS. 4a-4e shoW a second embodiment of the
`subject invention;
`[0016] FIGS. 5a-5e shoW a third embodiment of the
`subject invention;
`[0017] FIG. 6 shoWs a fourth embodiment of the subject
`invention;
`[0018] FIG. 7 shoWs a prosthesis including skirts formed
`in accordance With the ?rst and third embodiments of the
`subject invention; and
`[0019] FIG. 8 shoWs a prosthesis including a plurality of
`skirts serially arranged formed in accordance With the sec
`ond embodiment of the subject invention.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`[0020] The invention herein provides an implantable pros
`thesis Which may be used as a graft to replace a portion of
`a bodily passageWay (e.g., vascular graft), or may be used
`Within a bodily passageWay to maintain patency thereof,
`such as an endovascular stent-graft. In addition, the pros
`thesis can be used in other bodily applications, such as the
`esophagus, trachea, colon, biliary tract, urinary tract, pros
`tate and the brain.
`[0021] The implantable prosthesis of the subj ect invention
`is representatively depicted in FIGS. 2a-2b and generally
`designated With the reference numeral 10. The prosthesis 10
`is particularly Well suited to act as an endovascular graft or
`stent-graft. The prosthesis 10 includes a tubular body 12
`Which is preferably radially-expandable. The tubular body
`12 may be composed of one or more layers of knoWn
`materials used in endovascular graft formation, including,
`but not limited to a polymeric material (e.g., polytetra?uo
`roethylene), a textile material (e.g., polyethylene terephtha
`late (PET)), natural tissue (e.g., saphenous vein or collagen),
`and combinations thereof. As With knoWn endovascular
`graft and stent-graft construction, the tubular body 12 is
`preferably collapsible and radially-expandable to a natural
`resting diameter. In addition, as shoWn in FIG. 2b, the
`
`prosthesis 10 may also include a radially expandable support
`member 14, and one or more tubular bodies 12A, 12B. The
`radially expandable support member 14 may be disposed
`interiorly of the tubular body 12A; exteriorly of the tubular
`body 12B; or interposed betWeen one or more of the tubular
`bodies 12A, 12B. Optionally, multiple radially expandable
`support members 14 may be provided at one or more of the
`aforementioned locations. The radially expandable support
`member 14 may be ?xed to the tubular bodies 12A, 12B
`using any technique knoWn to those skilled in the art, such
`as bonding (e.g., With a thermoplastic ?uoropolymer adhe
`sive (such as
`Additionally, With the radially expand
`able support member 14 being interposed betWeen the
`tubular bodies 12A, 12B, the tubular bodies 12A, 12B may
`be ?xed together through any interstices formed in the
`radially expandable support member 14. The radially
`expandable support member(s) 14 Will impart the prosthesis
`10 (and thus any of the tubular bodies 12; 12A, 12B) With
`a natural resting diameter. In further describing the inven
`tion, reference Will be made to a tubular body 12 in the
`singular; it is to be understood that the reference to a singular
`tubular body 12 includes reference to the variations of the
`prosthesis described, including use of multiple tubular bod
`ies 12A, 12B and one or more of the radially expandable
`support member 14.
`[0022] The radially expandable support member 14 may
`be of any construction knoWn in the prior art Which can
`maintain patency of the prosthesis 10. For example, as
`shoWn in FIG. 2b, the radially expandable support member
`14 may be a stent. The particular stent 14 shoWn in FIG. 2b
`is fully described in commonly assigned US. Pat. No.
`5,693,085 to Buirge et al., and the disclosure of US. Pat. No.
`5,693,085 is incorporated by reference herein. The stent may
`be an intraluminally implantable stent formed of: a metal,
`such as stainless steel, tantalum, or niobium; a temperature
`sensitive material, such as Nitinol; or, alternatively, a super
`elastic alloy or suitable polymer. Although a particular stent
`construction is shoWn With reference to the present inven
`tion, various stent types and stent constructions may be
`employed for the uses anticipated herein. Among the various
`useful radially expandable members 14 included are, With
`out limitation, self-expanding stents and balloon expandable
`stents. The stents may be capable of radially contracting as
`Well. Self-expanding stents include those that have a spring
`like action Which causes the stent to radially expand or stents
`Which expand due to the memory properties of the stent
`material for a particular con?guration at a certain tempera
`ture. Other materials are of course contemplated such as
`platinum, gold, titanium, and other biocompatible materials,
`as Well as polymeric stents. The con?guration of the radially
`expandable support member 14 may also be chosen from a
`host of geometries. For example, Wire stents can be fastened
`in a continuous helical pattern, With or Without Wave-like
`forms or Zig-Zags in the Wire, to form a radially deformable
`stent. Also, individual rings or circular members can be
`linked together such as by struts, sutures, or interlacing or
`locking of the rings to form a tubular stent.
`[0023] Furthermore, the prosthesis 10 may be used With
`additional layers Which may be formed of polymeric mate
`rial, textile and/or natural tissue, such as natural vein or
`collagen. Furthermore, any layer or portion of the prosthesis
`10 may be impregnated With one or more therapeutic and
`pharmacological substances prior to implantation of the
`prosthesis 10 for controlled release over an extended dura
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 10 of 13
`
`

`

`US 2003/0236567 A1
`
`Dec. 25, 2003
`
`tion. It is anticipated that the prosthesis 10 can be partially
`or Wholly coated With hydrophilic or drug delivery-type
`coatings Which facilitate long-term healing of diseased ves
`sels. Such a coating is preferably bioabsorbable, and is
`preferably a therapeutic agent or drug, including, but not
`limited to: anti-thrombogenic agents (such as heparin, hep
`arin derivatives, urokinase, and PPack (dextrophenylalanine
`proline arginine chloromethylketone); anti-proliferative
`agents (such as enoxaprin, angiopeptin, or monoclonal anti
`bodies capable of blocking smooth muscle cell proliferation,
`hirudin, and acetylsalicylic acid); anti-in?ammatory agents
`(such as dexamethasone, prednisolone, corticosterone,
`budesonide, estrogen, sulfasalaZine, and mesalamine); anti
`neoplastic/antiproliferative/anti-miotic agents (such as
`paclitaxel, S-?uorouracil, cisplatin, vinblastine, vincristine,
`epothilones, endostatin, angiostatin and thymidine kinase
`inhibitors); anesthetic agents (such as lidocaine, bupiv
`acaine, and ropivacaine); anti-coagulants (such as D-Phe
`Pro-Arg chloromethyl keton, an RGD peptide-containing
`compound, heparin, antithrombin compounds, platelet
`receptor antagonists, anti-thrombin antibodies, anti-platelet
`receptor antibodies, aspirin, prostaglandin inhibitors, plate
`let inhibitors and tick antiplatelet peptides); vascular cell
`groWth promotors (such as groWth factor promotors, groWth
`factor receptor antagonists, transcriptional activators, and
`translational promoters); vascular cell groWth inhibitors
`(such as groWth factor inhibitors, groWth factor receptor
`antagonists, transcriptional repressors, translational repres
`sors, replication inhibitors, inhibitory antibodies, antibodies
`directed against groWth factors, bifunctional molecules con
`sisting of a groWth factor and a cytotoxin, bifunctional
`molecules consisting of an antibody and a cytotoxin); cho
`lesterol-loWering agents; vasodilating agents; and agents
`Which interfere With endogenous vascoactive mechanisms.
`
`[0024] With reference to FIGS. 2a and 2b, the prosthesis
`10 is provided With at least one skirt 16 (Which may be
`formed in various geometric con?gurations) that extends
`from the tubular body 12. The skirt 16 terminates in a
`peripheral edge 18 that is spaced from a juncture betWeen
`the skirt 16 and the tubular body 12. As described more fully
`beloW, the peripheral edge 18 is free and displaceable to a
`greater diameter than the diameter of the tubular body 12,
`particularly at its natural resting diameter. In this manner,
`portion(s) of the peripheral edge 18 can be displaced to
`contact, and form a seal With a surrounding Wall. Irregu
`larities and/or Wall displacement (occurring such as from
`aneurysm neck expansion) can be responded to by the skirt
`16 in minimizing endoleaks about the prosthesis 10.
`
`[0025] The skirt 16 may be formed of any material used in
`preparing the tubular body 12. In addition, the skirt 16 may
`be coated With, for example, collagen, ?brin, hyaluronic
`acid, chitosan, and/or other polysaccharide. The skirt 16 may
`act as a passive barrier against endoleaks by encouraging
`coagulation and clot formation by being coated With ?brin.
`Accordingly, the skirt 16 need not form a completely tight
`mechanical (i.e., “active”) seal With the surrounding Wall,
`but rely on a passive clot barrier to inhibit endoleakage. The
`skirt 16 may also be formed to encourage cell ingroWth, such
`as endothelial cell ingroWth, With surface con?gurations
`(e.g., roughened surface) and/or by being formed or coated
`With material susceptible to cell ingroWth (e.g., velour).
`With cellular ingroWth, the skirt 16 may attach to a sur
`rounding Wall, and not only support a cellular barrier against
`
`endoleakage, but also responsively move With the surround
`ing Wall due to its connection thereWith.
`
`[0026] One or more of the skirts 16 may be provided to
`form seals along various points about the prosthesis 10. In
`addition, the skirt 16 may be positioned to seal an appro
`priate point or points relative to the prosthesis 10. The skirt
`16 may also be oriented as needed, for example, relative to
`blood ?oW. The prosthesis 10 may be used in other blood
`vessels, and, as indicated above, in other bodily passage
`Ways. As Will be appreciated by those skilled in the art, the
`prosthesis 10 can be used to form seals not only at points
`cephalad of an abdominal aortic aneurysm, but also points
`caudad (e.g., at the iliac arteries).
`[0027] As Will also be appreciated by those skilled in the
`art, the skirt 16 may be formed in various con?gurations to
`alloW for a free peripheral edge 18 Which is at least partially
`displaceable to a larger diameter than the tubular body 12.
`Various embodiments of the skirt 16 are described herein to
`illustrate operation of the invention, although other embodi
`ments may be resorted to consistent With the teachings
`herein.
`
`[0028] With reference to FIGS. 3a-3e, a ?rst embodiment
`of the skirt 16 is shoWn, Which is tapered doWnWardly
`relative to the tubular body 12. Thus, With reference to FIG.
`3b, the skirt 16 is intended to be tapered to a greater diameter
`in a direction of blood ?oW, as represented by the arroW. The
`skirt 16 is joined to the tubular body 12 at a juncture located
`at, or in proximity to, an upstream end of the tubular body
`relative to blood ?oW. FIGS. 3a-3c shoW the skirt being
`joined at an upstream end 20, While FIG. 3a' shoWs the skirt
`16 being spaced from the end 20. It is preferred that the skirt
`16 be spaced a distance t in the range of 2-15 mm from the
`end 20.
`
`[0029] In an initial state, as shoWn in FIG. 3a, the skirt 16
`lies ?at or relatively ?at in overlapping a portion of the
`tubular body 12. With this con?guration, the pro?le of the
`prosthesis 10 can be minimiZed in easing implantation
`thereof. Once implanted, such as in an aorta AA, as shoWn
`in FIG. 3c, at least a portion of the peripheral edge 18 may
`be displaced in response to an irregularity in the aorta AA
`lumen and/or aneurysm neck expansion (FIG. 3c shoWs a
`portion of the aorta AA having been displaced from the
`original position shoWn in dashed lines due to aneurysm
`neck expansion). The tubular body 12 Will expand maxi
`mally to its natural resting diameter in response to the
`lumenal irregularities and/or expansion. The skirt 16 alloWs
`for expansion beyond that natural resting diameter.
`
`[0030] With the ?rst embodiment, the peripheral edge 18
`is displaced by scaffold 22 Which supports the skirt 16. It is
`preferred that limited support be provided for the skirt 16; as
`such, the scaffold 22 preferably includes a plurality of
`circumferentially-spaced tines Which are self-expanding,
`either due to inherent spring action and/or due to memory
`properties of the constituent material. The skirt 16 is joined
`to the tubular body 12 using any technique knoWn to those
`skilled in the art, such as bonding. To facilitate radial
`expansion of the scaffold 22, individual members thereof
`must be mounted to the tubular body 12 such as to provide
`suf?cient counterforce to alloW for radial expansion. It is
`preferred that point contacts betWeen the members of the
`scaffold 22 and the tubular body 12 be avoided. With
`reference to FIG. 36, the scaffold 22 may include scaffold
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 11 of 13
`
`

`

`US 2003/0236567 A1
`
`Dec. 25, 2003
`
`members 22A supporting the skirt 16, and counterforce
`members 22B attached to the tubular body 12. Expansion of
`the skirt 16 is attained by displacing the scaffold members
`22A, With the counterforce members 22B providing coun
`terforce to allow such displacement. The tines of the scaffold
`22 are shoWn to be straight in the ?gures, but may be of other
`shapes, such as Wavy, S-shaped, bent and so forth. As an
`alternative con?guration, the skirt 16 may be more fully
`supported, Wherein the scaffold 22 includes a plexus of
`elements (e.g., Wire members) arranged in a typical stent
`con?guration. The elements may be of any construction
`Which provides sufficient stiffness to alloW for displacement
`of the skirt 16. For example, the elements may be of
`polymeric material or textile (e.g., the skirt 16 may be
`pleated to de?ne the scaffolding 22). Here, selected elements
`may be formed and appropriately attached to provide coun
`terforce.
`
`[0031] With radial expansion of the skirt 16, as shoWn in
`FIG. 3c, radial force is directed outWardly through the
`peripheral edge 18 to facilitate seal formation against a
`surrounding Wall. In this manner, an active mechanical seal
`may be formed against endoleakage. Moreover, portion(s) of
`the skirt 16 may be responsively displaced Where needed.
`
`[0032] With reference to FIGS. 4a-4e, a second embodi
`ment of the subject invention is shoWn, Where the skirt 16 is
`formed With a generally cylindrical shape. More particularly,
`With reference to FIG. 4b, the skirt 16 is shoWn in an
`expanded state, Wherein a ?rst portion 24 of the skirt 16
`extends radially outWardly from the tubular body 12, and a
`second portion 26 of the skirt 16 depends doWnWardly
`therefrom to terminate at the peripheral edge 18. The ?rst
`portion 24 is supported by the scaffold 22, Which as shoWn
`in the ?gures, is preferably a plurality of circumferentially
`spaced arcuate tines. As shoWn in dashed lines in FIG. 4a,
`the tines alternatively may be formed straight, or in another
`shape. As a further alternative, and as With the ?rst embodi
`ment, the scaffold 22 may also be a plexus of various
`elements.
`[0033] Preferably, the second portion 26 is unsupported,
`although the scaffold 22 may extend from the ?rst portion 24
`to at least partially support the second portion 26; or,
`alternatively, a separate scaffold (not shoWn) may be pro
`vided to support the second portion 26.
`
`[0034] As With the ?rst embodiment, the skirt 16 is
`preferably located to be spaced at a short distance (2-15 mm)
`from the proximal end 20, although it may also be located
`at the end 20. With reference to FIG. 4a, the prosthesis 10
`is implanted With the skirt 16 being in a relatively ?at state.
`Once implanted, as shoWn in FIG. 4c, the skirt 16 expands
`to prevent endoleakage in a similar manner as described
`above With respect to the ?rst embodiment. With arcuate
`tines, hoWever, skirt displacement Will also include a rota
`tional element.
`
`[0035] As a variation of the second embodiment, the ?rst
`portion 24 may be trough-shaped as shoWn in FIGS. 4d and
`46. In an expanded, or partially expanded state, the scaffold
`22 is con?gured such that the ?rst portion 24 includes a
`trough-shaped depression Which may be V-shaped,
`U-shaped or the like. As shoWn in FIG. 46, With the skirt 16
`being at least partially expanded, blood ?oW that bypasses
`the tubular body 12 (Which Would normally constitute
`endoleakage) applies hemodynamic pressure as indicated by
`
`arroW 1 into the ?rst portion 24 Which, then results in normal
`force applied against the sides of the trough (arroWs 2).
`These forces cumulatively attempt to ?atten the ?rst portion
`24, resulting in further radial expansion (arroW 3) of the skirt
`16, and, thus, a tighter seal against a surrounding Wall. With
`the alternative variation of FIGS. 4d and 46, potential
`endoleakage is converted to increased sealing force.
`
`[0036] With reference to FIGS. 5a-5e, a further embodi
`ment of the subject invention is depicted, Wherein the skirt
`16 is formed to be tapered upWardly. Generally, the same
`comments apply as set forth With respect to the ?rst embodi
`ment depicted in FIGS. 3a-3a', except that the skirt 16 is
`inverted from that shoWn in the ?rst embodiment. In addi
`tion, With respect to the third embodiment, it is preferred that
`the skirt 16 not be supported by a scaffold 22, although
`optionally it may be so supported. Furthermore, drain holes
`28 may be formed through the tubular body at locations
`beloW the skirt 16 so as to alloW blood ?oW trapped by the
`skirt 16 to be re-introduced into the main stream of blood
`?oW through the tubular body 12.
`
`[0037] Without scaffold 22, expansion of the skirt 16
`occurs under pressure of endoleakage. As shoWn in FIG. 5c,
`a portion or portions of the peripheral edge 18 are separated
`from the tubular body 12 in response to such stray blood
`?oW.
`
`[0038] As a variation of the third embodiment, a trough
`shaped ?rst portion 30 may be provided, similarly con?g
`ured to that disclosed With respect to the second embodi
`ment. As shoWn in FIG. 52, the ?rst portion 30 is preferably
`unsupported by any scaffold, but is responsive to blood ?oW
`pressure to cause radially-outWard expansion.
`
`[0039] With reference to FIG. 6, a fourth embodiment of
`the subject invention is shoWn Which is similar to the
`variation of the second embodiment shoWn in FIGS. 4d and
`4e. Particularly, the ?rst portion 24 is trough-shaped and
`formed as discussed above. The second portion 26 is,
`hoWever, tapered doWnWardly and preferably aWay from the
`tubular body 12. In contrast, the second portion 26, as shoWn
`in FIGS. 4d and 46, is generally parallel to the tubular body
`12. To enable the tapered shape of the second portion 26,
`scaffold 22 is provided to support it. As shoWn in FIG. 6, the
`scaffold 22 may extend continuously from the ?rst portion
`24. Alternatively, a separate scaffold (not shoWn) may be
`provided to support the second portion 26. Other geometric
`con?gurations and combinations of geometric con?gura
`tions can be resorted to in forming the skirt 16.
`
`[0040] In addition, as Will be understood by those skilled
`in the art, more than one of the skirts 16 may be provided on
`the tubular body 12 to provide redundant seals. For example,
`With reference to FIG. 7, the prosthesis is provided With one
`of the skirts 16a (formed in accordance With the third
`embodiment herein) and, a second of the skirts 16b (formed
`in accordance With the ?rst embodiment herein). As such,
`the second skirt 16b provides a redundant seal to prevent
`endoleakage Which may bypass the skirt 16a. Other com
`binations of skirts and skirt embodiments are possible. For
`example, With respect to FIG. 8, a plurality of the skirts
`16A, 16B, 16C .
`.
`. formed in accordance With the second
`embodiment herein, may be serially arranged.
`
`[0041] As is readily apparent, numerous modi?cations and
`changes may readily occur to those skilled in the art, and
`
`Edwards Lifesciences Corporation, et al. Exhibit 1105, Page 12 of 13
`
`

`

`US 2003/0236567 A1
`
`Dec. 25, 2003
`
`hence it is not desired to limit the invention to the exact
`construction operation as shoWn and described, and accord
`ingly, all suitable modi?cation equivalents may be resorted
`to falling Within the scope of the invention as claimed.
`
`What is claimed is:
`1. An implantable prosthesis comprising:
`at least one radially-expandable tubular body; and
`
`at least one skirt extending from, and at least partially
`overlapping, said tubular body, said skirt terminating in
`a peripheral edge that is spaced from a juncture
`betWeen said skirt and said tubular body, at least
`portions of said peripheral edge being free and dis
`placeable to a greater diameter than said tubular body.
`2. Aprosthesis as in claim 1, Wherein said skirt is at least
`partially supported by a scaffold.
`3. A prosthesis as in claim 2, Wherein said scaffold is at
`least partially formed of self-expandable material.
`4. A prosthesis as in claim 2, Wherein said scaffold
`includes a plurality of circumferentially-spaced tines Which
`generally extend from said tubular body.
`5. A prosthesis as in claim 4, Wherein said tines are
`arcuate.
`6. A prosthesis as in claim 1, Wherein at least one hole is
`formed through said tubular body Which is overlapped by
`said skirt.
`7. A prosthesis as in claim 1, Wherein said skirt includes
`a ?rst portion that is extendable circumferentially outWardly
`from said tubular bod