United States Patent (19)
`Shockey et al.
`
`TELESCOPING GUIDE CATHETER SYSTEM
`54)
`Rick L. Shockey, Eagan. Minn.;
`(75) Inventors:
`Donald S. Baim, Newton, Mass.;
`Kevin L. Cronk, Maple Grove; Rocky
`R. J. Campbell, Maple Plain, both of
`Minn.
`(73) Assignee: Schneider (USA) Inc., Minneapolis,
`Minn.
`(21) Appl. No.: 730,373
`(22
`Filed:
`Jul. 11, 1991
`
`(63)
`
`(56)
`
`Related U.S. Application Data
`Continuation of Ser. No. 464,324, Jan. 12, 1990, aban
`doned.
`51) int. Cl. ............................................. A61M 25/00
`52 U.S. C. .................................... 604/282; 606/194;
`128/657
`58) Field of Search ............................... 606/192, 194;
`604/96-103, 265, 280, 282; 128/656-658,772
`References Cited
`U.S. PATENT DOCUMENTS
`3.485,234 12/969 Stevens .
`4.323,071 4/1982 Simpson et al. .
`4,564.014 1/1986 Fogarty et al. ..................... 606/94
`4,581,017 4/1986 Sahota .
`4,616,652 10/1986 Simpson .......................... 128/657 X
`4,636,346 l/1987 Gold et al. .
`4,669.465 6/1987 Moore .
`4,774,949 10/1988 Fogarty.
`4,784.636 11/1988 Rydell .
`4,87,613 4/1989 Jaraczewski et al. ............... 128/658
`4.863,442 9/1989 DeMello et al. ...
`604/282
`4,883.459 11/1989 Calderon .........
`... 604/28
`4.886.506 12/1989 Lougren et al.
`4,898,591 2/1990 Jang et al. ........................... 604/282
`
`US005120323A
`Patent Number:
`11)
`45) Date of Patent:
`
`5,120,323
`Jun. 9, 1992
`
`
`
`4,932,413 6/1999 Shockey et al. .................... 128/657
`4,976,689 12/1990 Buchbinder et al. ..
`... 604/95
`4,976,691 l2/1990 Sahota ................................... 604/96
`FOREIGN PATENT DOCUMENTS
`277366 8/1988 European Pat. Off. .
`303487 2/1989 European Pat. Off. .
`Primary Examiner-John D. Yasko
`Assistant Examiner-Adam J. Cermak
`Attorney, Agent, or Firm-Haugen and Nikolai
`(57)
`ABSTRACT
`The guide catheter system for use in the treatment of
`coronary artery disease includes a first single-lumen
`catheter of a relatively large internal diameter to pass a
`second guide catheter therethrough. The first guide
`catheter comprises an elongated flexible tube having a
`stainless steel braid embedded in the wall thereof for
`imparting desired torqueability characteristics to it. The
`first guide catheter is intended to be inserted at an ap
`propriate point in the vascular system and then ad
`vanced until its distal end reaches the coronary ostium.
`The second guide catheter is fabricated by extruding a
`plastic, such as polyurethane thermoplastic resin over a
`tubular Teflon (R) core and because it is to be used
`within the lunen of the first catheter, it need not include
`a braided structure within its walls to prevent it from
`kinking. This allows the second catheter to be suffi
`ciently slim to permit it to be advanced into a coronary
`artery while allowing fluids to be perfused between the
`outer wall of the second guide and the inner wall of the
`first guide catheter while still providing a sufficiently
`large inner lumen to pass a working catheter, e.g., an
`angioplasty or atherectomy catheter. An atraumatic tip
`is attached to the distal end of the second guide cathe
`tet.
`
`19 Claims, 1 Drawing Sheet
`
`Page 1
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`Medtronic Exhibit 1854
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`

`

`U.S. Patent
`
`June 9, 1992
`
`5,120,323
`
`
`
`
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`\VON AVIV, 67ZZZZZZZZZZZZZZZ
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`t-)----
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`32
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`Medtronic Exhibit 1854
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`1.
`
`10
`
`15
`
`20
`
`TELESCOPING GUIDE CATHETER SYSTEM
`This is a continuation of copending U.S. application
`Ser. No. 07/464,324, filed on Jan. 12, 1990 now aban
`doned.
`BACKGROUND OF THE INVENTION
`I. Field of the Invention
`This invention relates generally to improved catheter
`apparatus for facilitating the recanalization of a ste
`nosed coronary artery and more particularly to an im
`proved guide catheter system whereby a guide catheter
`member can be advanced beyond the coronary ostium
`and into the coronary artery itself up to the point of the
`stenosis.
`II. Discussion of the Prior Art
`In treating coronary artery disease, a variety of surgi
`cal techniques are employed to recanalize an occluded
`or partially occluded artery segment without requiring
`open heart surgery. Using the technique pioneered by
`A. Gruntzig, a catheter having an expander (balloon) at
`its distal end is routed through the vascular system and
`ultimately into the coronary artery with the balloon
`being juxtaposed with the stenotic lesion. Once so posi
`tioned, the balloon is inflated to compress the plaque
`into the wall of the blood vessel, thus restoring patency.
`In another procedure, referred to as an atherectomy,
`a catheter having a rotatable cutter at its distal tip is
`advanced through the vascular system and when the tip
`is made to abut the atheroma, a motor at the proximal
`end of the catheter is used to drive the cutter to surgi
`cally "tunnel" through the lesion. In this regard, refer
`ence is made to the Rydell U.S. Pat. No. 4,784,636,
`assigned to applicant's assignee.
`Still others have incorporated a fiber optic bundle in
`a catheter and a laser is used to burn through the plaque
`comprising the arterial blockage. In this regard, refer
`ence is made to the Moore et al U. S. Pat. No. 4,669,465,
`assigned to GV Medical, Inc., of Minneapolis, Minn.
`The foregoing are exemplary of working catheters,
`i.e., the catheters that are directly involved in the recan
`alization through expansion, excision or ablation. To
`properly position the working catheter, it is also neces
`sary that a guide catheter be utilized. A guide catheter
`45
`of the prior art typically comprises an elongated, flexi
`ble tube having an internal lumen sufficiently large to
`receive and pass the working catheter therethrough. In
`that the catheters are generally introduced into the
`femoral artery and then advanced through the vascular
`system to the heart, the guide catheter must possess a
`characteristic of "torqueability" meaning that it can
`transmit a twisting force applied at its proximal end to
`the distal end to facilitate the ability to steer it through
`the appropriate vascular branches. The torqueability
`55
`characteristic is achieved by the appropriate choice of
`materials for the guide catheter shaft or by incorporat
`ing a braided sheath of wire strands embedded in the
`wall of the guide catheter. Those wishing further infor
`mation concerning the construction of a typical prior
`art guide catheter are referred to the Stevens U.S. Pat.
`No. 3,485,234, assigned to the Cordis Corporation of
`Miami, Fla.
`When it is considered that the lumen of the guide
`catheter must be large enough to pass the working cath
`65
`eter and that the guide catheter shaft must exhibit ac
`ceptable torqueability and stiffness characteristics, it
`tends to dictate a guide catheter having a relatively
`
`5, 120,323
`2
`large outside diameter. In fact, it has not been possible
`in the past to advance the distal end of the conventional
`guide catheter beyond the coronary ostium. Where the
`site of the lesion in the coronary artery is several centi
`meters beyond the ostium and it becomes necessary
`during the recanalization procedure to exchange work
`ing catheters, damage may be done to the delicate tissue
`of the intima.
`SUMMARY OF THE INVENTION
`In accordance with the present invention, a system of
`guide catheters is provided whereby a guide catheter
`can be configured sufficiently small in outside diameter
`that it will pass distally of the ostium into the coronary
`artery to be treated while maintaining a sufficiently
`large internal diameter for allowing a working catheter
`to be passed therethrough and guided thereby. More
`specifically, the guide catheter system includes a some
`what conventional guide catheter of the type described
`above, but instead of passing the working catheter di
`rectly through its lumen, a second guide catheter is
`telescopingly received within the lumen of the first
`guide catheter. The second guide catheter comprises an
`elongated thin-wall tube of polytetrafluoroethylene
`(Teflon (R)) which is coated on its exterior with a blend
`of polyurethanes. Because the second guide catheter is
`to be passed through the lumen of the first guide cathe
`ter, it does not require a braided layer to provide the
`torqueability necessary to route the guide catheter from
`its femoral artery entry point to the heart. Instead, it
`tracks the lunen of the first guide catheter. Because the
`need for a braided layer is obviated, it can be made of a
`sufficiently thin wall that its outside diameter is suffi
`ciently small that the second guide catheter can be ad
`vanced beyond the ostium and into the coronary artery
`itself. To minimize damage to the endothelial layer, the
`second guide catheter is equipped with a soft tip which
`is appropriately rounded to avoid sharp edges which
`can damage the arterial wall. The soft tip may prefera
`bly be formed from a polyurethane resin exhibiting low
`durometer as compared to the durometer of the poly
`urethane blend coating the Teflon tubular core. By
`lining the second guide catheter with the Teflon core,
`its trackability and pushability property is enhanced.
`The Teflon layer provides a low coefficient of friction
`with the working catheter to be inserted.
`With the second guide catheter advanced so that its
`distal end portion is contained within the coronary
`artery to be treated, it provides backup support for the
`blood vessel during the recanalization procedure and
`allows repeated exchanges of working catheters with a
`minimum of damage to the intima.
`The foregoing features, objects and advantages of the
`invention will become more apparent to those skilled in
`the art from the following detailed description of a
`preferred embodiment, especially when considered in
`conjunction with the accompanying drawings in which
`like numerals in the several views refer to correspond
`ing parts.
`DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a side view, partially cross-sectioned of the
`guide catheter system of the present invention; and
`FIG. 2 is a diagram illustrating the use of the present
`invention in recanalizing a stenosed coronary arterial
`blood vessel.
`
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`5
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`O
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`3
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`Referring first to FIG. 1, there is indicated generally
`by numeral 10 the guide catheter system in accordance
`with the present invention. It is seen to include a first,
`relatively large diameter guide catheter 12, comprising
`an elongated, flexible plastic tube which would typi
`cally be approximately 100 cms. in length and fabricated
`primarily from a blend of polyurethanes and containing
`a braided wire sheath 14 within its walls. In that the
`outer guide catheter 12 is intended to be routed through
`the vascular system from a peripheral site such as an
`incision into the femoral artery, the wire braid affords
`the desirable torque properties whereby twisting the
`proximal end 16 will transmit a corresponding torque to
`the distal end 18 of the catheter 12. The catheter 12 may
`be in the range of from about 9 French to 5 French and
`designed to have an internal lumen in the range of from
`20
`7 French to 3.5 French. Bonded to the proximal end 16
`of the outer catheter 12 is a conventional catheter hub
`20. The catheter structure thus far described may be
`produced in accordance with the Stevens U.S. Pat. No.
`3,485,234 which describes a manufacturing process
`25
`whereby a catheter is produced having a precisely di
`mensioned lumen and a braided wire sheath disposed
`entirely within the plastic comprising the catheter's
`wall.
`To reduce the likelihood and/or extent of trauma to
`the endothelial lining of the blood vessels through
`which the outer catheter 12 is routed, it is preferably
`provided with an atraumatic tip 22 which is appropri
`ately attached to the end of the outer tubing member.
`The soft tip 22 will typically be formed from a polyure
`35
`thane blend exhibiting a lower durometer than the plas
`tic comprising the remainder of the catheter. It may be
`attached and otherwise configured as set out in the Van
`Tassel et al. U.S. Pat. No. 4,531,943 assigned to appli
`cant's assignee.
`40
`Coaxially disposed and loosely fitting within the
`lumen 24 of the first or outer catheter 12 is a second
`catheter 26 which is of a somewhat greater length than
`the first catheter 12. The body of the catheter 26 com
`prises an internal tubular core 28 which is made from
`45
`polytetrafluoroethylene (Teflon (R)) having a wall
`thickness of approximately 0.0005 inches The Teflon
`tube, while supported on a cylindrical mandrel, is then
`coated with a suitable plastic, preferably a blend of
`polyurethanes so that the composite outside diameter is
`SO
`in the range of from 8 French to 3 French.
`As mentioned above, the inside diameter of the outer
`guide catheter 12, if designed to be 7 French, leaves a
`predetermined clearance between the two when a sec
`ond catheter 26 of, say, 6 French, is telescopingly re
`55
`ceived within the lunen 24 of the outer catheter 12.
`This permits the perfusion or aspiration of liquids
`through the annular gap between inner wall of the outer
`catheter 12 and the outer wall of the inner catheter 26.
`Appropriately bonded to the distal end portion of the
`second or inner catheter 26 is an atraumatic tip 30 again
`formed from a suitable plastic material exhibiting a low
`durometer rating.
`The catheter 26, being 6 French, may have an inter
`nal diameter of 0.063 inches which is sufficiently large
`to pass a working catheter (not shown) therethrough.
`As mentioned above, the working catheters employed
`may include those for angiography, atherectomy, as
`
`5, 120,323
`4.
`well as various pressure monitoring or fiber optic de
`vices.
`Shown threaded through the lumen of the inner tubu
`lar catheter 26 is an elongated flexible, helically wound
`stainless steel guidewire 32.
`Having described the constructional features of the
`guide catheter system of the present invention, consid
`eration will next be given to its mode of use. In this
`regard, reference is made to FIG. 2 which diagrammati
`cally depicts the various coronary arterial blood vessels,
`both anterior and posterior with the remainder of the
`heart eliminated. Thus, numeral 34 identifies the femo
`ral artery leading to the descending aorta 36, the aortic
`arch 38 and the aortic valve 40. Located adjacent the
`aortic arch 38 and slightly above the valve 40 is the left
`coronary ostium 42 and the right coronary ostium 44.
`Leading away from the ostium 42 is the left coronary
`artery 46 which joins to the circumflex branch 48 from
`which the obtuse marginal branch 50 and the intermedi
`ate branch 52 extend.
`The left anterior descending artery is identified by
`numeral 54 and branching from it are the septal arteries
`56 and 58.
`Extending from the right coronary ostium 44 is the
`right coronary artery 60 which leads to the posterior
`descending artery 62. Let it be assumed that a stenosis
`exists at 64 in the left anterior descending artery 54 and
`that it is desired to treat the lesion with an angioplasty
`balloon-type working catheter. In carrying out the pro
`cedure, an incision is made and an introducer (not
`shown) is inserted into the femoral artery 34. The first
`catheter 12 is then passed retrograde up the descending
`aorta 36 and beyond the aortic arch 38 until its distal tip
`22 abuts the coronary ostium 42. Next, a guidewire 32 is
`passed through the lumen of the first guide catheter 12
`and maneuvered by twisting and advancing distally
`until the guidewire passes down the left anterior de
`scending artery 54 and beyond the location of the lesion
`64. Once the guidewire 32 is so positioned, the telescop
`ing guide catheter 26 is passed over the wire 32 by
`feeding the distal tip 30 over the guidewire and feeding
`it through the hub 20 of the outer guide catheter 12 and
`thence through the lumen 24 thereof until it exits the
`distal end 18 of the outer catheter through the left coro
`nary ostium 42 and down the left anterior descending
`branch 54. Once the distal tip 30 of the inner telescoping
`guide catheter 26 is proximate the site of the lesion, the
`working catheter (not shown) with its distal balloon
`may now be fed through the lumen 31 of the inner guide
`catheter and over the guide wire 32. Because the inte
`rior wall of the inner guide catheter is lined with a layer
`of a lubricious plastic, such as Teflon, the coefficient of
`friction between the working catheter and the wall of
`the inner guide catheter is low, thus enhancing the
`trackability of the working catheter through the lumen
`of the inner guide catheter 26. Once the distal balloon of
`the working catheter is advanced across the stenosis,
`dilatation of the affected blood vessel can take place.
`Once the balloon has been advanced across the lesion, it
`is the physician's choice whether to pull the inner guide
`back into the lumen of the outer guide or not.
`It may also occur that the physician will want to
`withdraw one working catheter in favor of a replace
`ment working catheter. By leaving the internal guide
`catheter 26 in position, the exchange may take place
`without repeatedly drawing the working catheter back
`and forth over the endothelial lining of the blood vessel.
`
`15
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`10
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`5,120,323
`6
`5
`mal end to the distal end and having a tube wall
`Instead, the arterial branch remains supported by the
`characterized by reinforcing means internal to the
`guide catheter 26 during the exchanges.
`tube wall for providing the necessary torque trans
`This invention has been described herein in consider
`mission required to enable routing of the outer
`able detail in order to comply with the Patent Statutes
`guide catheter through the arterial vascular sys
`and to provide those skilled in the art with the informa
`tion needed to apply the novel principles and to con
`tem; and
`an inner elongated guide catheter adapted to be tele
`struct and use such specialized components as are re
`scopingly received within and passed through the
`quired. However, it is to be understood that the inven
`lumen of the outer guide catheter and including
`tion can be carried out by specifically different equip
`flexible tubular core of a lubricous material con
`ment and devices, and that various modifications, both
`structed without reinforcing means surrounded by
`as to the equipment details and operating procedures,
`an outer coating of a polymeric material and hav
`can be accomplished without departing from the scope
`ing a proximal end, a distal end and an outside
`of the invention itself.
`diameter sufficiently small to fit with a predeter
`What is claimed is:
`mined clearance within the lumen of the outer
`1. A method of performing recanalization of a ste
`guide catheter;
`nosed coronary artery of interest comprising the steps
`wherein the distal end of the unreinforced inner guide
`of:
`catheter is adapted to pass beyond the distal end of
`introducing a first elongated, hollow, flexible, plastic,
`the outer guide catheter and navigate vascular
`relatively large diameter, reinforced-wall torque
`areas beyond the distal end of the outer guide cath
`transmitting guide catheter having a proximal end
`20
`eter through which the outer guide catheter itself
`and a distal end at a predetermined location in the
`cannot be safely passed including the area beyond
`vascular system and advancing the first guide cath
`the coronary ostia into a coronary artery of interest
`eter until the distal end thereof reaches the coro
`to be recanalized; and
`nary ostia;
`wherein the lumen of the tubular core of the inner
`inserting a second, elongated, hollow, flexible, plas
`guide catheter is of sufficient diameter to pass a
`tic, relatively smaller diameter unreinforced guide
`working catheter therethrough.
`catheter having a tubular core a polytetrafluoro
`4. The telescoped dual guide catheter system of claim
`ethylene polymeric material sheathed in an outer
`3 further including a tubular tip member of a polymer
`cylindrical coating of a second polymeric material
`material of relatively low durometer affixed to the distal
`and a distal tip member of a material of relatively
`end of the inner guide catheter, wherein the tip member
`low durometer relative to the other materials of the
`is further characterized by a rounded distal end to en
`second guide catheter affixed to the distal end of
`counter and minimize damage to the endothelial lining
`the second guide catheter, wherein the tip member
`of the vascular system including the coronary artery of
`is further characterized by a distal end shaped to
`interest.
`encounter and minimize damage to the endothelial
`35
`5. The telescoped dual guide catheter system of claim
`lining of coronary artery of interest by the advanc
`ing second guide catheter;
`4.
`wherein the reinforcing means internal to the tube
`advancing the second guide catheter until the distal
`wall of the outer guide catheter is braided wire;
`end of the second catheter passes beyond the distal
`wherein the core of the inner guide catheter is poly
`end of the first guide catheter and into the coro
`tetrafluoroethylene; and
`nary artery of interest adjacent the stenosis to be
`wherein the outer coating comprises a blend of poly
`canalized;
`slidably introducing a working catheter having a
`urethane.
`6. The telescoped dual guide catheter system of claim
`proximal end and a distal end into the hollow tubu
`5 wherein the polymer tip material is a relatively soft
`lar core of the second guide catheter and advanc
`45
`polyurethane.
`ing the working catheter therealong until the distal
`7. The telescoped dual guide catheter as in claim 6
`end of the working catheter passes through and
`further including a molded plastic hub affixed to the
`extends beyond the distal end of the second guide
`proximal end of the inner guide catheter.
`catheter and into the stenosed area of the coronary
`8. The telescoped dual guide catheter of claim 6
`artery of interest; and
`wherein the wall of the inner catheter is thinner than the
`using the working catheter to accomplish recanaliza
`wall of the outer catheter tube.
`ton.
`9. The telescoped dual guide catheter as in claim 5
`2. The method of claim 1 wherein the outside diame
`further including a molded plastic hub affixed to the
`ter of the second guide catheter is in the range of from
`proximal end of the inner guide catheter.
`about 6.5 French to 3 French and the inside diameter of
`55
`10. The telescoped dual guide catheter of claim 5
`the first guide catheter is in the range of from about 7
`wherein the wall of the inner catheter is thinner than the
`French to 3.5 French.
`wall of the outer catheter tube.
`3. A telescoped dual guide catheter system for use in
`11. The telescoped dual guide catheter system of
`performing artery transluminal angioplasty or atherec
`claim 4 wherein the polymer tip material is a relatively
`tomy procedures in a coronary artery of interest having
`soft polyurethane.
`the ability to navigate coronary arteries comprising:
`12. The telescoped dual guide catheter as in claim 4
`an outer guide catheter comprising an elongated,
`further including a molded plastic hub affixed to the
`flexible plastic tuber having a proximal end and a
`proximal end of the inner guide catheter.
`distal end, having an outside diameter small enough
`13. The telescoped dual guide catheter system of
`to pass through the arterial vascular system from
`claim 3 wherein the outside diameter of the smaller
`an introducer site to the coronary ostia, the outer
`inner guide catheter is in the range of from about 6.5
`guide catheter further describing an internal lumen
`French to 3 French and the corresponding inside diam
`of a relatively large size extending from the proxi
`
`SO
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`5,120,323
`8
`7
`characterized by a braided metal reinforcing layer
`eter of the large outer guide catheter is in the range of
`internal to the tube wall for providing the neces
`from about 7 to 3.5 French.
`14. The telescoped dual guide catheter as in claim 13
`sary torque transmission required to enable routing
`further including a molded plastic hub affixed to the
`of the first guide catheter through the arterial vas
`proximal end of the inner guide catheter.
`cular system; and
`15. The telescoped dual guide catheter of claim 13
`an inner elongated guide catheter adapted to be tele
`wherein the wall of the inner catheter is thinner than the
`scopingly accommodated by, received within, and
`wall of the outer catheter tube.
`passed through the lumen of the outer guide cathe
`16. The telescoped dual guide catheter system of
`ter and including an unreinforced flexible tubular
`claim 3
`core of a lubricous polytetrafluoroethylene sur
`wherein the reinforcing means internal to the tube
`rounded by an outer coating of a polyurethane
`wall of the outer guide catheter is braided wire;
`blend material and having a proximal end, a distal
`wherein the core of the inner guide catheter is poly
`end and an outside diameter sufficiently small to fit
`tetrafluoroethylene; and
`with a predetermined clearance within the lumen
`wherein the outer coating comprises a biend of poly
`of the outer guide catheter;
`urethane.
`wherein the distal end of the unreinforced inner guide
`17. The telescoped dual guide catheter as in claim 3
`catheter is adapted to pass beyond the distal end of
`further including a molded plastic hub affixed to the
`the outer guide catheter and navigate vast vascular
`proximal end of the inner guide catheter.
`areas beyond the distal end of the outer guide cath
`18. The telescoped dual guide catheter of claim 3
`20
`eter through which the outer guide catheter itself
`wherein the wall of the inner catheter is thinner than the
`cannot be safely passed including the area beyond
`wall of the outer catheter tube.
`the coronary ostia into a coronary artery of interest
`19. A telescoped dual guide catheter system for use in
`to be recanalized;
`performing artery transluminal angioplasty or atherec
`wherein the lumen of the tubular core of the inner
`tonny procedures in a coronary artery of interest having
`guide catheter is of sufficient diameter to pass a
`the ability to navigate coronary arteries comprising:
`working catheter therethrough;
`an outer guide catheter comprising an elongated,
`a tubular tip member of a polymer material of rela
`flexible plastic tube having a proximal end and a
`tively low durometer polyurethane affixed to the
`distal end, having an outside diameter small enough
`distal end of the inner guide catheter, the tip mem
`to pass through the arterial vascular system from
`ber being further characterized by a rounded distal
`an introducer site to the coronary ostia, the outer
`end to encounter and minimize damage to the en
`guide catheter further describing an internal lumen
`dothelial lining of the coronary artery of interest.
`of a relatively large size extending from the proxi
`mal end to the distal end and having a tube wall
`
`O
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`15
`
`k
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`k
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`t
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`

`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`5,120,323
`PATENT NO. :
`June 9, 1992
`DATED
`Rick L. Shockey et all
`INVENTOR(S) :
`it is certified that error appears in the above-identified patent and that said Letters Patent is hereby
`corrected as shown below:
`
`Column 5, 1ine 27, delete 'a', and insert --of
`
`In Column 5, line 63, delete "tuber", and insert -- tube --
`
`In column 6, line 6, delete "and".
`
`In Column 6, line lO, delete "lubricous" and insert -- lubricious
`
`In column 6, line 37, after "4", insert -- : - -
`
`In Column 7, line 2, after "7" insert -- French --
`
`In column 7, line lO, after "3", insert -- : - -
`In column 8, line l0, delete "lubricous" and insert -- lubricious
`
`Signed and Sealed this
`Fourteenth Day of September, 1993
`4. (e?ou
`
`Attest:
`
`Attesting Officer
`
`Commissioner of Patents and Trademarks
`
`BRUCE LEHMAN
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`Page 7
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`Medtronic Exhibit 1854
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