United States Patent [191
`Wolff et al.
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,830,003
`May 16, 1989
`
`[54] COMPRESSIVE STENT AND DELIVERY
`SYSTEM
`[76] Inventors: Rodney G. Wolff, 468 W. Eagle Lake
`Dr., Maple Grove, Minn. 55369;
`Creg W. Dance, 812 Benton St.,
`Anoka, Minn. 55303; Brice Letac,
`134 rue du Renard, 76.000 Roven,
`France; Alain Cribier, 76150
`Maromme, Maromme, France
`[21] Appl. No.: 208,252
`[22] Filed:
`Jun. 17, 1933
`[51] Int. cu ........................................... .. A61M 29/00
`[52] U.S.C1. ................................ .. 128/343; 623/1
`[53] Field of Search ............ .. 623/1; 600/37; 128/343,
`123/334 R, 335
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4,503,569 3/1985 Dotter ............................... .. 128/303
`4,553,545 11/1985 Maass et al. .
`128/341
`4,580,568 4/1986 Gianturco
`.. 128/348
`
`4,647,416 3/1987 Seiler . . . . . . .
`
`. . . . . . ._ 623/1
`
`128/344
`4,649,922 3/1987 Wiktor
`128/ 343
`4,655,771 4/1987 Wallsten ..
`4,733,665 3/1988 Palmaz .............................. .. 128/ 343
`
`OTHER PUBLICATIONS
`Palmaz et al., Expandable Intraluminal Vascular Graft:
`A Feasibility Study, Feb., 1986, Surgery, pp. 199-205.
`Palmaz et al., Expandable Intralurninal Graft: A Prelim
`inary Study, 1985, Radiology, pp. 73-77.
`Palrnaz et al., Atherosclerotic Rabbit Aortas: Expand
`able Intraluminal Grafting, 1986, Radiology, pp.
`723-726.
`Primary Examiner-Richard J. Apley
`Assistant Examiner-James Prizant
`[57]
`ABSTRACT
`A cylindrical shaped stent to prevent arterial acute
`closure and subsequent restenosis formed of longitudi
`nal wires of biocompatible metal. The wires are welded
`together in pairs at alternate ends with each pair of
`wires bent into a V-section. The wires are all formed
`into a cylinder welded closed to form the stent. The
`stent is compressed and loaded into an outer catheter by
`a special tool. The stent is positioned and released for
`self expansion in situ by an inner catheter. A guide wire
`through both assists in threading the catheters through
`blood vessels.
`,
`
`10 Claims, 2 Drawing Sheets
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-1
`
`

`

`US. Patent May 16,1989
`
`Sheet 1 Vof2
`
`‘4,830,003
`
`2
`
`m:- .
`run-1"" -
`gm“ ‘ x!
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-2
`
`

`

`US. Patent May 16,1989 -
`
`Sheet 2 of2
`
`4,830,003
`
`/ / / / /
`
`l j
`
`FIG.“
`
`|/////////@
`
`32 36
`
`34
`
`100
`
`27
`
`24
`
`25
`
`23
`
`I8
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-3
`
`

`

`1
`
`COMPRESSIVE STENT AND DELIVERY SYSTEM
`
`10
`
`25
`
`35
`
`20
`
`4,830,003
`2
`uses a wire of 0.018 inches in diameter which is equiva
`lent to 0.04572 centimeters and a bend ratio of no more
`than 0.2 centimeters. This is a ratio of approximately 1
`to 4.37. Since the wire is bent to form the zig-zag shape
`there must be some angle formed between adjacent legs
`which limits the minimum spacing between these legs.
`A large amount of force is necessary to compress the
`stent when the stent is short since energy is only stored
`in the bends. If the stent is made relatively short in
`length with respect to the diameter then the amount of
`force necessary to bend the wires in order to compress
`the stent becomes large. This again is because the bends
`are the only place that energy is stored. Only if the stent
`is made relatively long with respect to the diameter is
`the force required to hold a vascular vessel open re
`duced. The claims speci?ed stents of speci?c sizes 5.5
`cm long><4 cm diameter fully expanded and 3.0 cm
`long><2.5 cm diameter fully expanded. This relatively
`long length and diameter results in forces which are
`compatible with the vascular system but can obviously
`only be used in very large peripheral arteries and veins.
`Another effect is the absolute minimum size to which
`the stent can be compressed. As mentioned earlier the
`angular relationship between adjacent wires at the ends
`limits the minimum spacing between adjacent wires
`which in turn limits the minimum diameter of the stent
`to a size which is incompatible with coronary arteries
`' and like sized vessels.
`In addition, since the diameter of the wire and the
`material composition is continuous throughout its
`length, these parameters are not varied to provide dif
`ferent characteristics at the bends vs. the straight sec
`tion of the zig-zag. Since only the material in the bends
`themselves are involved in storing energy the charac
`teristics of the bends versus the straight sections are not
`necessarily compatible for all of these requirements in
`particular when the additional necessity for utilizing a
`bio-compatible material is added. Further, to complete
`and close the zig-zag pattern made up of a single wire a
`sleeve must be placed over the two ends to connect
`them together which results in an anomoly at that point.
`We have taken an entirely different approach to the
`problem to avoid these inherent limitations of the previ
`ous system by using individual parts welded together to
`avoid?‘ the necessity for a bend in the material com
`pletely. This overcomes all of the limitations and re
`strictions enumerated above. Our stent is adaptable for
`use in coronary arteries with their extremely small di
`ameter where the other approach because of the bend
`diameters results in a stent which cannot be reduced to
`the required coronary size, unless a far fewer number of
`wires are used. If far fewer numbers of wires are used,
`this greatly limits both the force applied to and the
`surface coverage of the vessel wall.
`The delivery system has no means of locating the
`position of the stent relative to the stenosis site from the
`exterior of the body. No guide wire is used and in use
`the stent is inserted from the proximal end of the cathe
`ter.
`
`TECHNICAL FIELD
`The present invention relates to an intravascular stent
`which can be applied within the peripheral or coronary
`arteries of a living animal or human being to maintain
`patency after a balloon angioplasty, either a percutane
`ous transluminal coronary angioplasty (PCTA) or a
`percutaneous transluminal angioplasty (PTA) proce
`dure. The stent comprises a tubular shaped structure
`made up of individual wires welded together which can
`be compressed along the axis to a smaller tubular diame
`ter to fit within an outer catheter to hold the stent com
`pressed, which is used along with an inner catheter to
`release the stent and a guide wire which are used after
`a balloon angioplasty to insert, position and ?x the stent
`permanently at the angioplasty site to prevent acute
`reocclusion and subsequent restenosis. The construction
`of the stent is such that the dimensions and material of
`the device can be selected to provide a given radial
`force against the interior of the artery adequate to main
`tain the shape of the vessel against any force tending to
`close it. These closure forces include not only acute
`reclosure due to intimal dissections, flaps and spasm but
`also plaque restenosis. The latter is prevented or slowed
`by neo-intimal overgrowth on the stent itself. The
`length of the stent can also be varied or more than one
`stent can be used at a single location to accommodate
`curvature and other unusual arterial characteristics.
`Radiopaque marker material on the end of the inner and
`outer catheters permits locating the stent at the desired
`site by external monitoring or the stent itself can be
`made of radiopaque material.
`BACKGROUND ART
`In US. Pat. No. 4,553,545 a device which can be
`expanded after insertion in a blood vessel by rotating a
`wire coil about its length to reduce the number of turns
`and thereby increase the diameter is disclosed. In US.
`Pat. No. 4,503,569 a helically wound coil is formed of a
`memory Nitinol alloy which has a transition tempera
`ture in the range of 115 degrees to 125 degrees Faren
`heit. After placement in the vessel this coil is heated to
`regain its original larger shape. These approaches re
`quire either heat or mechanical forces to be applied to
`the apparatus, in order to expand the stent at the site,
`with the resulting trauma to the body.
`In U.S. Pat. No. 4,580,568 a stent is formed of stain
`less steel wire of 0.018 inches diameter arranged in a
`closed zig-zag pattern. The stent is compressed to re
`duce its size in order to position it within a sheath,
`which is used to locate the stent within the vascular
`system. A ?at-ended catheter is used through the sheath
`to hold the stent in place in the passageway while the
`sheath is withdrawn, allowing the stent to expand into
`its original shape to hold the passageway open and
`enlarged. According to the speci?cations the only en
`ergy stored in this stent to restore it to its original shape
`is stored in the bends.
`This device and delivery system suffers from a num
`ber of severe limitations and problems. Fashioning the
`stent from a continuous wire folded in a zig-zag fashion
`requires a sharp bend in the wire at each end of the stent
`to form this shape. A wire can only be bent at a ratio
`which is some multiple of the wire diameter. The exact
`multiple will vary according to the property of the
`material. The example cited in the patent as claimed
`
`45
`
`50
`
`55
`
`65
`
`SUMMARY OF THE INVENTION
`The present invention is characterized by a prothesis
`stent which is useful in conjunction with a balloon angi
`oplasty, either a ‘percutaneous transluminal coronary
`angioplasty (PCTA) or a percutaneous transluminal
`angioplasty (PTA) of diseased coronary arteries or any
`other larger arteries to prevent acute reclosure or reste
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-4
`
`

`

`4,830,003
`3
`nosis of the artery after the procedure. The stent is
`applied immediately after the balloon angioplasty as an
`extension of the procedure. The stent is in the form of
`an open ended tube formed by a set of angled wires
`which are welded together at the ends resulting in an
`offset angle, then formed into a tubular shape and the
`end wires welded together. Using this construction the
`wires are connected obliquely from one end to the op
`posite end. The wires are made of spring material which
`can be bent closer together to form a smaller diameter
`tube and will store energy in the straight segments, but
`when the compressive force is removed the wires will
`be urged by the force from the oblique wires to self
`expand to the original tubular diameter. This restoring
`force must be adequate to maintain the artery in an
`expanded position as well as resist all other forces tend
`ing to close the artery. The stent structure chosen re
`sults in a small percentage of this structure supporting
`the artery to allow tissue overgrowth of a neointimal
`lining to prevent or retard restenosis from the plaque or
`other ?brotic growths. The stent is inserted percutane
`ously using an outer catheter to enclose and compress
`the stent, and an inner catheter which has the same size
`and the same diameter as the compressed stent to re
`lease the stent. A guide wire through the inner catheter
`assists in positioning the stent at the stenosis site while
`an optional guide catheter over the outer catheter aids
`in inserting the inner and outer catheters into the artery.
`The guide wire can be the same guide wire used in the
`previous balloon angioplasty. The location of the stent
`itself is determined by monitoring radiopaque markers
`on the catheter ends using a fluroscope or similar device
`to permit locating the stent at the proper site. The stent
`itself can also be made of radiopaque material, such as
`platinum or platinum iridium to readily permit locating
`the stent at the stenosis site using the same fluroscope
`techniques. The stent ensures patency and prevents
`acute reocclusion and restenosis at this location.
`
`25
`
`4
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`Referring to FIG. 1, individual wires 10 making up
`the device are shown before bending and shaping. In
`FIG. 2 welds 12 are shown connecting alternate ends of
`wires 10. The wires used can be any of the biocompati
`ble metals. Biocompatible metals include some 300 se
`ries stainless steels, such as 316LSS, platinum and plati
`num-irridium alloys, certain cobalt-chromium alloys
`such as MP35N, and unalloyed titanium. The welds
`typically range in length from 1 to 2 millimeters for
`coronary artery applications. As an example, a
`Nd/Y AG laser can be used at approximately 5 watts
`power to accomplish this weld although it is also possi
`ble to use other weld processes here such as resistance
`welding.
`In FIG. 3 bends 14 in wires 10 form a “V” at each
`weld 12. Twelve of these wires 10 shaped and welded
`together as shown in FIG. 3 are shown in FIG. 4
`formed into a cylindrical con?guration to form a tubu
`lar shaped stent 100 with cylinder completed by weld
`ing together the end wires. Bends 14 can be set after
`wires 10 are welded as illustrated in FIG. 3 or can be set
`before the weld, in either case the wires are spaced
`apart by these bends such that only a small percentage
`of the cylinder surface area, on the order of 10 to 25
`percent, is made up of metal. The advantages of this
`minimal metal surface area will be discussed later.
`This method of forming stent 100 permits utilizing
`any desired wire with any required characteristics since
`the ends of the wires are simply welded together. As an
`alternative, wires 10 can be bent to the desired angle,
`the bent wires formed and held into a cylinder shape,
`and the total structure welded closed using simple jigs
`and ?xtures. The variables permitted by this approach
`include wire size, material used, wire length, weld
`length, the angle of bend and the cylinder diameter. For
`coronary arteries wires as small a 0.004 inches in diame
`ter can be used with wire lengths which range from 4 to
`15 millimeters and stent diameters of from 2 to 5 milli
`meters. The number of wires used in such coronary
`stents can vary from 8 to 16 over the range of stent
`diameters. These extremely small sizes which are neces
`sary for coronary artery applications, can be readily
`manufactured and tailored for any desired coronary
`artery requirement. These ranges of wire size and stent
`size permit the external metal surface area of typically
`10 to 25 percent of the total cylinder area stated above.
`The larger peripheral arteries can utilize a wire diam
`eter of 0.006 to 0.016 inches with a length of 10 to 25
`millimeters and a stent diameter of 5 to 15 millimeters.
`The number of wires used here will vary from 8 to 16
`over the range of stent diameters.
`In FIG. 4 a side view of stent 100 is shown. This
`illustrates the tubular shape which the individual wires
`10 form. FIG. 5 shows the uniform spacing between
`pairs of wires 10 at the ends where the wires are welded
`together while FIG. 6 shows the uniform spacing be
`tween the individual wires at the center of the stent
`length.
`In FIGS. 4, 5, and 6 stent 100 is shown completely
`unrestrained with wires 10 at their maximum separation
`storing no energy. In FIG. 7, stent 100 is shown com
`pressed and enclosed within an outer catheter 16 with a
`guide wire 18 threaded through the longitudinal axis of
`stent 100. Stent 100 is sized such that the wire 18 will
`readily pass through the stent when it is compressed.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a front view of the individual wires aligned
`for attachment.
`FIG. 2 is a front view of individual wires welded
`45
`together.
`FIG. 3 is a front view of the welded wire bent prior
`to being formed into a cylinder.
`FIG. 4 is a side view of the stent.
`FIG. 5 is a schematic representation of FIG. 4 taken
`along 5——5.
`FIG. 6 is a schematic representation of FIG. 4 taken
`along 6—6.
`FIG. 7 is a longitudinal-section of an artery with
`inner catheter, outer catheter, guide wire and loaded
`stent before placing stent in artery.
`FIG. 8 is the view of FIG. 7 after placing stent in
`artery by retracting outer catheter and releasing the
`stent.
`FIG. 9 shows the inner and outer catheters and guide
`wire assembled together with the Y-connector hemosta
`sis valves and guiding catheter.
`FIG. 10 is a cross-section view of the stent loading
`tool in position for loading the stent into the outer cath
`eter.
`FIG. 11 is the cross-section view of FIG. 10 with the
`stent loaded into the outer catheter.
`
`65
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-5
`
`

`

`15
`
`25
`
`35
`
`4, 830,003
`5
`6
`An inner catheter 20 is sized to fit within outer catheter
`to stent 100 is known, consequently the location of the
`16 but is sized and of materials such that inner catheter
`distal end of the stent can be determined. Further, as
`will readily slide within the outer catheter. Radiopaque
`discussed earlier, if stent 100 itself is made radiopaque, it
`markers 22 at the ends of both inner catheter 20 and
`can readily be located by a fluoroscope. Guide wire 18
`outer catheter 16 provides a capability of determining
`being more flexible than catheters 16 and 20 is used to
`the location of these catheters by using X-ray excitation
`steer the catheters into the artery. Guide catheter 21 is
`and a fluoroscope monitoring device external to the
`previously positioned just adjacent to the artery, and
`body. An optional guide catheter 21 encloses outer
`the remainder of the assembly slid through the guide
`catheter 16. All of these items are inserted within an
`catheter to complete the procedure. A fluoroscope
`artery 28, as will be described later. Artery 28 has a
`adjacent the patient’s body indicates when stent 100 is
`stenosis site 30 which encircles the artery. In FIG. 8
`located adjacent stenosis site 30 in the position shown in
`stent 100 is shown released from outer catheter 16 sup
`FIG. 7. Then valve cap 25 is loosened, inner catheter 20
`porting stenosis site 30. The equipment and procedure
`held in position by hub 23 and valve 24 moved proxi
`used to accomplish the release of stent 100 at stenosis
`mally to withdraw outer catheter 16 from about the
`site 30 will be described later.
`inner catheter until the stent is released as shown in
`In FIG. 9 the assembly of inner catheter 20, outer
`FIG. 8. During this process inner catheter 20 holds stent
`catheter 16, guide wire 18 and guide catheter 21 are
`100 in place as outer catheter 16 is withdrawn. When
`shown. Standard Y-connector hemostasis valves 24 and
`stent 100 is released from outer catheter 16 the stent will
`26 in conjunction with respective valve adjuster caps 25
`self expand as shown to support and ?xate against the
`and 27 control bleeding. Hemostasis valve 24 has a
`area of stenosis site 30. After stent 100 is released then
`centered hole sized to permit inner catheter 20 to slide
`the entire assembly is withdrawn leaving only the stent
`through. Hemostasis valve 26 has a centered hole to
`in place within the vessel. This simple procedure re
`permit outer catheter 16 to slide through. Hub 23 has a
`quires only the same general catheterization techniques
`centered hole sized to permit guide wire 18 to slide
`as the balloon angioplasty to locate stent 100 at the
`through. This arrangement permits inner catheter 20
`stenosis site.
`and outer catheter 16 to slide relative to each other,
`Placement of stent 100 is thus a complimentary pro
`whenever caps 25 and 27 are loosened which frees re
`cedure to a balloon angioplasty which is performed
`spective O-rings in each, not shown, from a closed
`during the same catheterization and which lengthens
`position to permit the adjacent parts to slide. After the
`the balloon angioplasty procedure by only a few min
`adjustments are made caps 25 and 27 are again tightened
`utes. This brief extension of time results in this proce
`which again closes the O-rings against the adjacent
`dure being well tolerated by the body. When stent 100
`parts which again prevents relative movement and seals
`expands it bears against the interior wall of the vessel at
`against blood loss. Guide catheter 21 encloses outer
`stenosis site 30 to provide a radial outwardly directed
`catheter 16 and is secured to hemostasis valve 26 by
`force in all directions.
`proximal hub 26A.
`This force has two major effects. One effect is to hold
`In use a balloon angioplasty procedure is performed
`the vessel open against any inner directed force, such as
`on the artery 28 shown in FIG. 7 to expand, remodel, or
`spasm, and essentially tacks up intimal flaps or dissec
`enlarge the vessel lumen through stenosis site 30. Guide
`tions generated by prior balloon angioplasty to assure
`wire 18 and guide catheter 21 can be the same items
`the patency of the vessel. This force is tailored by a
`used in the balloon angioplasty and left in place to guide
`selection of the parameters which were discussed ear
`outer catheter 16. After the balloon angioplasty proce
`lier. The second effect of this force is to securely ?xate
`dure then guide wire 18, inner catheter 20, outer cathe
`wires 10 within the interior wall of vessel 28. This sec
`ter 16 and stent 100 are assembled as shown in FIGS. 7
`ond effect will assist in the early regeneration of tissue
`and 9 and located within artery 28 with the stent previ
`overgrowth or neointimal over the wires 10 of stent 100
`ous loaded in the end of the outer catheter, and the inner
`making restenosis less likely. The small percentage of
`catheter bearing just proximal to the stent with the
`metal surface area, noted earlier, permits this early re
`outer catheter enclosed in guide catheter 21, as shown
`generation, and also aids in prevention of acute closure
`in FIG. 9. The method of loading stent 100 in this fash
`due to thrombosis.
`ion will be described later. All of these parts are previ
`As mentioned earlier, the spring force developed by
`ously sterilized then threaded through the vessels in the
`wires 10 is'tailored for the given procedure. The force
`same manner and using the same path as that used for
`the balloon angioplasty procedure while monitoring the
`must be suf?cient to maintain artery 28 fully open and
`location of radiopaque markers 22 by illuminating the
`to also resist vasoconstrictive forces, spasm and the
`possible progressive development of an additional
`site by x-ray and observing the markers by a ?uoro
`plaque buildup at the location of stenosis site 30. The
`scope adjacent to the site. The stent 100, if made from
`force must not be excessive beyond these requirements
`one of the radiopaque materials, can also be monitored
`to determine its location.
`however to avoid traumatization of the vessel wall.
`Guide wire 18 is run inside inner catheter 20 and both
`The diameter of stent 100, when squeezed to fit
`the inner and outer catheter 20 are locked together at
`within outer catheter 16, is reduced from two to six
`their proximal ends during the insertion and location of 60
`times in size. This range of size adjustments plus the
`variation in spring constant possible permits the adjust
`stent 100 at the stenosis site by tightening valve caps 25
`and 27 as discussed earlier and illustrated in FIG. 9.
`ment of the expansion forces to the amount desired.
`Since inner catheter 20 bears against the proximal end
`As mentioned, typical sizes for stent 100 have a range
`of stent 100 as shown in FIG. 7, this will insure that the
`from a minimum external diameter of 2 to 4 millimeters
`stent is held in the same relative position with respect to
`when compressed to fit within outer catheter 16 to 5 to
`locked catheters 16 and 20 during this insertion and
`15 millimeters when released within a large arterial
`location of stent 100 within stenosis site 30. The distance
`vessel, to a range from a minimum external diameter of
`from the end of inner catheter 20 and outer catheter 16
`l to 1% millimeters when compressed within outer cath
`
`40
`
`45
`
`50
`
`55
`
`65
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-6
`
`

`

`8
`
`4,830,003
`7
`1. A stent comprising:
`eter 16 to 2 to 5 millimeters when released within-the
`(a) a number of equally dimensioned and shaped
`coronary arteries.
`wires each having an essentially straight center
`The length of stent 100 is likewise adapted to the
`segment with end segments bent at oblique angles
`length of the stenosis, which may be quite variable from
`with respect to said center segment such that oppo
`one case to the other, but should always be longer than
`site said end segments of each said wire are essen
`the stenotic segment. To make the applications of stent
`tially parallel one end segment to the other; and
`100 more ?exible, in case of tortuosities or angulations
`(b) said wires oriented and equally spaced to form a
`of the vessel at or before the plaque or lesions site, the
`tubular shape said bent end segments of each wire
`stent can be made shorter than the stenosis with two or
`oriented parallel, over lapping and contiguous with
`more stents placed in series to each other at the curved
`each adjacent wire, resulting in an acute angle
`vessel site or in outer catheter 10 so that an angulation
`being formed by said center segments of each adja
`of the catheter can be obtained at the point between the
`cent pair of wires, being secured together at all end
`end-to-end stents.
`segments; and
`In order to load stent 100 into outer catheter 16 a
`(c) said wires fashioned from spring metal biocompat
`special generally cylindrically shaped tool 32 is utilized.
`ible material, such that said wires can be bent to
`Tool 32, shown in cross section in FIG. 10, has a ?ared
`store energy in said wire segments to permit reduc
`opening 34 extending inwardly from one end of the
`ing the diameter of said stent to permit inserting
`cylinder and a circular bore 36 from the outer end with
`said stent into an outer catheter sized to receive
`a flat 38 between the two. Outer catheter 16 is inserted
`said stent when compressed to permit placing said
`within tool 32 to the bottom of bore 36, and inner cathe
`stent percutaneously within a living organism.
`ter 20 is positioned just short of entering the bore while
`2. The structure as in claim 1 and further comprising
`guide wire 18 extends completely through the tool
`an inner catheter sized to slideably ?t within an outer
`through both the bore and flared opening 34 of tool 32.
`catheter with the walls of said inner catheter sized to
`Outer catheter 16, inner catheter 20 and guide wire 18
`bear against the end of said stent when said inner cathe
`are locked together in this relationship using valve caps
`ter is ?t within said outer catheter and said stent com
`25 and 27 in the manner previously described. Stent 100
`pressed to ?t within said outer catheter.
`is then pushed through ?ared opening 34 which guides
`3. The assembly as in claim 2 wherein said inner and
`the stent past ?at 38 into bore 36 where it will spring
`outer catheter are tipped-with a radiopaque marker at
`open in the bore, as shown in FIG. 11, to complete the
`their distal ends adjacent to said stent.
`loading operation. Tool 32 is then removed from about
`4. The structure as in claim 2 wherein a guide wire is
`outer catheter 16.
`threaded coaxially through said inner catheter and said
`The stent is easy to fabricate and because the wires
`stent and wherein said inner catheter and said stent are
`are attached together by welding the wire size and
`sized to permit said guide wire to be slid through their
`material can be selected based only upon the desired
`respective centers as an aid in threading said catheters
`radial force and vessel size. Since welding results in a
`through a circulatory system.
`zero spacing between the wires at the point of attach
`5. The structure as in claim 4 wherein said outer
`ment any size wire can be welded. The extremely small
`catheter is threaded coaxially through a guide catheter
`stents necessary for the coronary arteries can thus be
`sized to slideably receive said outer catheter to provide
`readily fabricated using this technique.
`guiding means in said circulatory system for said outer
`The use of a radiopaque material as a marker on the
`and inner catheter.
`ends of the outer and inner catheters permits locating
`6. The structure as in claim 4 wherein said inner cath
`the stent precisely using only a ?uoroscope, as does
`eter can be slideably locked and sealed to said outer
`using a radiopaque material for the stent itself. The use
`catheter by means of a ?rst Y-connector hemostasis
`of an inner catheter which has a circular cross-section
`valve and said guide wire is exposed at the proximal end
`to positively engage the stent inside the outer catheter
`to permit slideable adjustment of said guide wire with
`assures that the stent will be released easily because the
`respect to said inner catheter.
`expansion forces of the compressed stent will cause it to
`7. The structure as in claim 5 wherein said inner cath
`bear against the inner wall of the outer catheter. This
`eter can be slideably locked and sealed to said outer
`device is simple in construction with parameters which
`catheter by means of a ?rst Y-connector hemostasis
`can readily be adapted to meet any requirement.
`valve and said outer catheter can be slideably locked
`The use of Y connector hemostasis valves 24 and 26
`and sealed to said guide catheter by means of a second
`permits the injection of liquid containing radiopaque
`Y-connector hemostasis valve and said guide wire is
`dye if it is necessary to determine the shape and size of
`exposed at the proximal end to permit slideable adjust
`the artery at the location of stent 100. If desired guide
`ment of said guide wire with respect to said inner cathe
`wire 88 can be removed after stent 100 is in place and
`ter.
`this space used to inject liquids.
`8. The assembly as in claim 1 wherein said wires are
`secured together by welding.
`While this invention has been described with refer
`ence to an illustrative embodiment, this description is
`9. The combination of claim 2 further comprising a
`generally cylindrical shaped tool having an axial bore
`not intended to be construed in a limiting sense. Various
`modi?cations of the illustrative embodiment, as well as
`from a ?rst end and a ?ared axial opening from a second
`other embodiments of the invention, will be apparent to
`end joined by a coaxial segment, said tool being sized to
`persons skilled in the art upon reference to this descrip
`provide a means for loading said stent within said outer
`tion. It is therefore contemplated that the appended
`catheter.
`claims will cover any such modifications or embodi
`10. The assembly as in claim 1 wherein said wires are
`ments as fall within the true scope of the invention.
`made of a radiopaque material.
`What is claimed is:
`*
`*
`i
`*
`
`15
`
`45
`
`50
`
`55
`
`60
`
`65
`
`*
`
`W.L. Gore & Associates, Inc.
`Exhibit 1004-7
`
`