(12) United States Patent
`Forsberg
`
`USOO6595952B2
`(10) Patent No.:
`US 6,595,952 B2
`(45) Date of Patent:
`Jul. 22, 2003
`
`(54) GUIDE CATHETER WITH BACKUP
`SUPPORT SYSTEM
`
`(75) Inventor: Andrew Forsberg, Plymouth, MN (US)
`
`--- - - -
`Casi
`(73) ASSignee: SIM
`systems Inc., Maple
`roVe,
`(US)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 66 days.
`
`(*) Notice:
`
`(21) Appl. No.: 09/754,713
`9
`(22) Filed:
`Jan. 4, 2001
`
`(65)
`
`Prior Publication Data
`US 2002/0087143 A1 Jul. 4, 2002
`(51) Int. Cl." ....................... A61M31/00; A61M 29/00;
`A61M 25/00
`(52) U.S. Cl. ..................... 604/93.01; 604/104; 604/525
`(58) Field of Search ................................ 604/6.16,507,
`604/508, 509, 93.01, 96.01, 104,523, 524,
`525,532; 606/194
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4/1994 Weldon ...................... 604/264
`5,306,262 A
`4/1994 Voda .......................... 600/435
`5,306,263 A
`6/1994 Rickerd ....................... 604/53
`5,322,509 A
`5,348,545 A 9/1994 Shani et al. ................ 604/281
`5,354,271. A 10/1994 Voda ........................... 604/49
`5,401,258 A
`3/1995 Voda .......................... 604/523
`5,445,625. A
`8/1995 Voda .......................... 604/281
`5,462,561. A 10/1995 Voda .......................... 606/144
`5,497,774 A
`3/1996 Swartz et al. ............... 128/658
`5,658.263 A 8/1997 Dang et al. ................. 604/280
`5,662,621. A
`9/1997 Lafontaine .................. 604/281
`5,680,873 A 10/1997 Berg et al. .................. 128/772
`5,800,413 A 9/1998 Swartz et al. ............... 604/280
`5,868,700 A 2/1999 Voda ........................... 604/49
`5,891,057. A 4/1999 Chaisson et al. ........... 600/585
`6,083,213 A 7/2000 Voda .......................... 604/500
`6,086,548 A 7/2000 Chaisson et al. ........... 600/585
`6,110,163 A 8/2000 Voda .......................... 604/523
`6,120,495 A 9/2000 Voda .......................... 604/523
`FOREIGN PATENT DOCUMENTS
`3-228773
`10/1991
`JP
`WO 92/12754
`8/1992
`WO
`WO 93/21983
`11/1993
`WO
`* cited by examiner
`Primary Examiner Ehud Gartenberg
`ASSistant Examiner John K Fristoe, Jr.
`74) Attorney, Agent, or Firm-Crompton, Seager & Tufte,
`y, Ag
`p
`9.
`LLC
`
`(57)
`
`ABSTRACT
`
`4,169,464 A 10/1979 Obrez ........................ 128/657
`4,781,682 A 11/1988 Patel ........................... 604/96
`An intravascular catheter (e.g. guide or diagnostic catheter)
`4,784,639 A 11/1988 Patel ........................... 604/53
`that includes a specially designed distal tip to provide
`4,813,930 A 3/1989 Elliott ......................... 604/53
`h
`dback
`t. The distal ti
`distal 2
`f
`4,813,938 A 3/1989 Raulerson ..
`... 604/158
`4.820,271. A 4/1989 Deutsch ....................... E enhanced back-up support. The distal tip (e.g., distal 2 cm o
`4832.028 A 5/1989 Patel
`128/344
`the shaft) has a lateral extent or profile (e.g., wave shape)
`4900787 A 3/1990 Danforth.
`... 604/95
`that is larger than the lumen of the coronary artery adjacent
`5,000,743 A 3/1991 Patel .........
`... 606/194
`the ostium when the tip is in a relaxed State. The over-sized
`5,016,640 A 5/1991 Ruiz ............
`... 128/658
`lateral extent causes the distal tip to frictionally engage the
`5,045,072 A 9/1991 Castillo et al.
`... 604/28O
`coronary artery and anchor within the ostium. The lateral
`5,098.412 A * 3/1992 Shiu .............
`... 600/585
`extent or profile of the distal tip may be decreased by
`5,122,125 A 6/1992 Deuss ..........
`... 604/282
`inserting a guide wire therethrough to facilitate insertion of
`5,163,928. A 11/1992 Hobbs et al......
`... 604/281
`the distal tip into the ostium. After the distal tip is inserted
`5,171,232 A 12/1992 Castillo et al. ...
`... 604/28O
`into the osti
`th
`ide wi
`b
`d to allow th
`5,188,619 A
`2/1993 Myers ..........
`so
`into the Osuum, the guide wire may be removed to allow ine
`5.195,990 A
`3f1993 Weldon
`604/264
`lateral extent of the distal tip to increase and thereby anchor
`5.203,776 A
`4/1993 Durfee.
`6026
`the distal tip in the ostium.
`5,231994. A 8/1993 Harmjanz ................... 128/772
`5,299,574 A
`4/1994 Bower ........................ 600/435
`15 Claims, 4 Drawing Sheets
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`U.S. Patent
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`Jul. 22, 2003
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`Sheet 1 of 4
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`US 6,595,952 B2
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`PRIOR ART
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`PRIOR ART
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`U.S. Patent
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`Jul. 22, 2003
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`Sheet 2 of 4
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`US 6,595,952 B2
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`Fig. 3
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`Fig. 4
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`U.S. Patent
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`Jul. 22, 2003
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`Sheet 3 of 4
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`US 6,595,952 B2
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`U.S. Patent
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`Jul. 22, 2003
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`Sheet 4 of 4
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`US 6,595,952 B2
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`1
`GUIDE CATHETER WITH BACKUP
`SUPPORT SYSTEM
`
`US 6,595,952 B2
`
`FIELD OF THE INVENTION
`The present invention generally relates to intravascular
`catheters. More specifically, the present invention relates to
`intravascular coronary guide catheters.
`BACKGROUND OF THE INVENTION
`Intravascular guide catheters are commonly used to guide
`therapeutic and diagnostic devices to remote locations in a
`patient's vascular System. For example, coronary guide
`catheters are commonly used to position a balloon catheter
`in a patient's coronary artery to perform a percutaneous
`transluminal coronary angioplasty (PTCA) procedure. An
`example of a conventional PTCA guide catheter 10 is
`illustrated in FIG. 1. The PTCA guide catheter 10 includes
`an elongate shaft 12 having a proximal end, a distal end and
`a lumen extending therethrough. A hub 14 is connected to
`the proximal end of the elongate shaft 12. The distal end of
`the elongate Shaft 12 includes a preformed curved portion 16
`and a distal tip portion 18, the geometry of which may vary
`depending on the particular vascular anatomy being navi
`gated.
`In a typical PTCA procedure, the distal end of the guide
`catheter 10 is inserted into the patient's femoral artery near
`the groin, and is advanced up the descending aorta 20, acroSS
`the aortic arch 22, and down the ascending aorta 28 until the
`distal tip 18 is seated in the ostium of the right coronary
`artery (RCA) 24 or the left coronary artery (LCA) 26 as
`illustrated in FIG. 2. Usually, approximately 1 mm-5 mm of
`the distal tip 18 is seated in the ostium. Once the distal tip
`18 is Seated in the ostium, a therapeutic or diagnostic device
`(e.g., a balloon catheter, an atherectomy catheter, an IVUS
`catheter, etc.) may be inserted into the lumen of the guide
`catheter 10, advanced therethrough, and navigated through
`the lumen of the coronary artery 24/26.
`Because the lumen of the coronary artery 24/26 is often
`restricted or tortuous, it is often difficult to navigate intra
`vascular devices therethrough, particularly when accessing
`distal vascular Sites. When resistance to advancement
`through the lumen of the coronary artery 24/26 is
`encountered, the physician typically applies additional push
`ing force to the intravascular device in an attempt to over
`come the resistance. If Significant resistance is encountered,
`the distal tip 18 of the guide catheter 10 tends to back-out of
`the ostium. When the distal tip 18 backs-out of the ostium,
`it is difficult if not impossible to advance the intravascular
`device any further and it is likely that the intravascular
`catheter will prolapse in the lumen of the ascending aorta 28.
`To address this problem, Some physicians attempt to
`deep-seat the distal tip 18 in the ostium. However, this
`deep-seating technique often causes misalignment between
`the lumen of the guide catheter 10 and the lumen of the
`coronary artery 24/26, thereby compromising advancement
`of intravascular devices therethrough. In addition, deep
`Seating the distal tip 18 may cause unnecessary trauma to the
`inside Surface of the coronary artery 24/26, potentially
`exacerbating the underlying clinical condition being treated
`and/or potentially causing additional clinical problems.
`AS an alternative to deep-seating, various means to pro
`vide a back-up Support have been proposed in the prior art.
`For example, U.S. Pat. No. 4,813,930 to Elliott and U.S. Pat.
`No. 5,098,412 to Shiu propose mechanisms which utilize a
`Structure to brace against the wall of the ascending aorta 28
`
`15
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`25
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`35
`
`40
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`45
`
`50
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`55
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`60
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`65
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`2
`opposite the ostium of the coronary artery 24/26 being
`accessed. Alternatively, U.S. Pat. No. 4,832,028 to Patel and
`U.S. Pat. No. 5,122,125 to Deuss propose an inflatable
`balloon at the distal end of the guide catheter to anchor the
`distal tip in the OStium of the coronary artery being accessed.
`Although each of these prior art designs may provide
`back-up Support to the guide catheter and thereby resist
`back-out from the ostium, each of the proposed embodi
`ments involve unnecessarily complexed designs which may
`compromise performance and handling of the guide catheter
`and which most certainly will increase the manufacturing
`cost of the guide catheter. Accordingly, there is a Substantial
`unmet need for a guide catheter which provides enhanced
`back-up Support without compromising performance and
`without Substantially increasing design complexity.
`
`SUMMARY OF THE INVENTION
`To avoid the Suboptimal performance associated with
`deep-seating conventional guide catheters and the unneces
`Sarily complex design of the balloon-anchor guide catheters
`of the prior art, the present invention provides a guide
`catheter that includes a Specially designed distal tip to
`frictionally engage a coronary artery adjacent its ostium. The
`intravaSclar catheter of the present invention, which may
`comprise a guide catheter or a diagnostic catheter, for
`example, is elegantly simple in design and does not com
`promise performance while providing enhanced back-up
`Support.
`In an exemplary embodiment, the present invention pro
`vides an intravascular coronary catheter, Such as a guide
`catheter or a diagnostic catheter, including a distal tip (e.g.,
`distal 2 cm of the shaft) that has a lateral extent or profile that
`is larger than the lumen of the coronary artery adjacent the
`ostium when the distal tip is in a relaxed State Such that the
`distal tip frictionally engages the coronary artery. The fric
`tional engagement with the coronary artery anchors the
`distal tip in the ostium and thereby provides back-up Sup
`port. Preferably, the distal tip is wave-shaped in two or three
`dimensions. The lateral extent or profile of the distal tip may
`be decreased (i.e., Straightened) by inserting a guide wire to
`facilitate insertion of the distal tip into the ostium. After the
`distal tip is inserted into the OStium, the guide wire may then
`be removed to allow the lateral extent of the distal tip to
`increase and thereby anchor the distal tip in the coronary
`artery.
`After the distal tip is anchored in the ostium, a balloon
`catheter or other intravascular device may be inserted
`through the guide catheter and into the lumen of the coro
`nary artery. If resistance to advancement through the lumen
`of the coronary artery is encountered, the anchored distal tip
`of the guide catheter provides Sufficient back-up Support to
`the balloon catheter in order to overcome the resistance to
`advancement. If Significant resistance is encountered, it is
`contemplated that by applying additional pushing force to
`the balloon catheter, the lateral extent of the distal tip may
`be further increased to further engage the coronary artery
`and thereby provide additional back-up Support.
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a plan view of a conventional PTCA guide
`catheter;
`FIG. 2 is a cross-sectional view of a portion of the aortic
`vasculature and a portion of the coronary vasculature with
`the conventional guide catheter of FIG. 1 disposed therein;
`FIG. 3 is a plan view of a guide or diagnostic catheter in
`accordance with an embodiment of the present invention;
`
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`US 6,595,952 B2
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`3
`FIG. 4 is a croSS-Sectional view taken along line 4-4 in
`FIG. 3;
`FIG. 5A is a detailed view of the distal tip of the catheter
`illustrated in FIG. 3 shown in the relaxed state;
`FIG. 5B is a detailed view of the distal tip of the catheter
`illustrated in FIG. 3 shown with a guide wire extending
`therethrough; and
`FIG. 6 is a cross-sectional view of a portion of the aortic
`vasculature and a portion of the coronary vasculature with
`the catheter of FIG. 3 disposed therein.
`
`4
`the distal tip 38 may have a wave-shape defining a plurality
`of peaks 50 and valleys 52. The distance between the
`furthermost apexes of the peaks 50 defines the lateral extent
`or profile P. The wave geometry may be Symmetrical or
`asymmetrical and may be two or three dimensional.
`The wave geometry of the distal tip 38 may be made by
`thermoforming techniques. For example, a wave-shaped
`mandrel may be inserted into the lumen 40 of the distal tip
`38 followed by the application of heat for a period of time.
`After cooling, the mandrel may be removed leaving the
`wave-shape formed in the distal tip 38. Preferably, the shaft
`diameter of the distal tip 38 does not vary despite the
`wave-shape. In particular, the distance between the peak 50
`and the valley 52 corresponds to the diameter of the remain
`der of the elongate shaft 32.
`As mentioned previously, the distal tip 38 has a lateral
`extent or profile P in the relaxed State that is larger than the
`lumen of the coronary artery being accessed. To facilitate
`insertion of the distal tip 38 into the ostium of the coronary
`artery being accessed, a guide wire 60 may be inserted into
`the lumen 40 and through the distal tip 38 to a decreased
`lateral extent or profile P. The decreased lateral extent or
`profile P is preferably less than the size of the lumen of the
`coronary artery being accessed Such that the distal tip is
`easily inserted therein. Upon removal of the guide wire 60
`from the lumen 40 of the distal tip 38, the distal tip 38
`elastically returns to its relaxed profile P, to frictionally
`engage the coronary artery adjacent the ostium. The distal
`tip is sufficiently flexible and elastic such that the lateral
`extent or profile of the distal tip 38 may elastically change
`between the relaxed profile P and the stressed profile P. By
`frictionally engaging the coronary artery adjacent the
`ostium, the distal tip 38 anchors the guide catheter 30 therein
`thereby providing enhanced back-up Support.
`The wave-shaped distal tip 38 may have a length between
`0.5 cm and 2.5 cm, a nominal shaft diameter between 4 F
`and 11 F, and a relaxed profile P between 1.1 and 2.0 times
`the nominal shaft diameter, depending on the size of the
`coronary lumen and the desired amount of frictional engage
`ment. Preferably, the length of the curved portion of the
`distal tip 38 is 1.5 cm or less to avoid the possible adverse
`effects of deep-seating the guide catheter 30 in the coronary
`artery.
`Refer now to FIG. 6 which illustrates the guide catheter
`30 disposed in the aortic and coronary vasculature of a
`patient. In use, the guide catheter 30 is inserted into the
`patient's vascular System utilizing conventional techniques
`until the distal tip 38 is adjacent the ostium leading to the
`right coronary artery 24 or left coronary artery 26. The guide
`wire 60 is typically disposed in the lumen 40 during this
`process Such that the lateral extent or profile of the distal tip
`38 is reduced as illustrated in FIG. 5B. The distal end of the
`guide wire 60 and the distal tip 38 of the guide catheter 30
`are inserted into the ostium of the coronary artery 26 being
`accessed. Once the distal tip 38 extends into the lumen of the
`coronary artery 26, the guide wire 60 is retracted in the
`proximal direction allowing the distal tip 38 to return to its
`relaxed (expanded) state as illustrated in FIG. 5A. In the
`relaxed or expanded state, the distal tip 38 frictionally
`engages the inside Surface of the coronary artery 26 to
`anchor the guide catheter 30 therein.
`Once the guide catheter 30 is positioned as illustrated in
`FIG. 6, another intravascular device Such as a balloon
`catheter may be inserted into the lumen 40 of the guide
`catheter 30 and navigated into the lumen of the coronary
`artery 26. If Substantial resistance to advancement through
`
`15
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`25
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`35
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`The following detailed description should be read with
`reference to the drawings in which similar elements in
`different drawings are numbered the Same. The drawings,
`which are not necessarily to Scale, depict illustrative
`embodiments and are not intended to limit the Scope of the
`invention.
`Refer now to FIG. 3 which illustrates catheter 30 in
`accordance with an exemplary of the present invention.
`Catheter 30 may be virtually any intravascular coronary
`catheter Such as a guide or diagnostic catheter. For Sake of
`simplicity and illustration, catheter 30 is described in terms
`of a guide catheter.
`Guide catheter 30 includes an elongate shaft 32 having a
`proximal end, a distal end and a lumen 40 extending
`therethrough. A conventional manifold 34 is connected to
`the proximal end of the elongate shaft 32. The elongate shaft
`32 includes a distal curved portion 36. The distal curved
`portion 36 may comprise a wide variety of Shapes and curve
`Styles depending on the particular vascular geometry being
`navigated. The elongate shaft 32 also includes a distal tip 38.
`The distal tip 38 generally has a lateral extent or profile that
`is larger than the lumen of the coronary artery being
`accessed when the tip 38 is in a relaxed state such that the
`distal tip frictionally engages the OStium of the coronary
`artery, as will be discussed in greater detail with reference to
`FIGS 5A and 5B.
`Refer now to FIG. 4 which illustrates a cross-sectional
`view of the elongate shaft 32 taken along line 4-4 in FIG.
`3. The elongate shaft 32 may comprise a wide variety of
`conventional catheter constructions including the multi
`layer construction illustrated in FIG. 4. The elongate shaft 32
`may comprise, for example, an inner lubricious polymeric
`layer 46, a wire braid reinforcement layer 44, and a poly
`meric outer layer 42. Those skilled in the art will recognize
`that the design and construction of the Shaft 32 may vary
`depending on the desired performance characteristics of the
`guide catheter 30.
`Refer now to FIGS. 5A and 5B which illustrate detailed
`views of the distal tip 38 of the guide catheter 30. FIG. 5A
`illustrates the distal tip 38 in the relaxed state, and FIG. 5B
`55
`illustrates the distal tip 38 in the stressed state as induced by
`a guide wire 60 extending therethrough. In the relaxed State,
`the distal tip 38 has a lateral extent or profile P. The relaxed
`profile P is greater than the inside diameter of the coronary
`artery being accessed adjacent its ostium Such that the distal
`tip 38 frictionally engages the inside Surface of the coronary
`artery. The stressed profile P is less than the inside diameter
`of the coronary artery being accessed Such that the distal tip
`38 may be easily inserted into the ostium thereof using guide
`wire 60.
`To provide a lateral extent or profile P that is greater than
`the size of the lumen of the coronary artery being accessed,
`
`50
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`40
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`45
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`60
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`65
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`Page 7
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`

`

`S
`the lumen of the coronary artery is encountered, additional
`pushing force may be applied to the balloon catheter to cause
`the lateral extent of the distal tip 38 to increase and thereby
`further engage the coronary artery 26. By this method, the
`guide catheter 30 provides enhanced back-up Support to
`Successfully navigate through restrictions and tortuous vas
`culature as may be encountered in PTCA procedures.
`Those skilled in the art will recognize that the present
`invention may be manifested in a variety of forms other than
`the Specific embodiments described and contemplated
`herein. Accordingly, departures in form and detail may be
`made without departing from the Scope and Spirit of the
`present invention as described in the appended claims.
`What is claimed is:
`1. An intravascular catheter providing access to a lumen
`of a coronary artery having an ostium, the catheter compris
`ing an elongate shaft having a proximal portion and a distal
`tip, the distal tip having a lateral profile that is larger than the
`lumen of the coronary artery adjacent the OStium when the
`tip is in a relaxed State Such that the distal tip frictionally
`engages the coronary artery, the distal tip having a lateral
`profile that is Smaller than the lumen of the coronary artery
`adjacent the ostium when the tip is in a stressed State.
`2. An intravascular catheter as in claim 1, wherein the
`elongate Shaft includes a single lumen.
`3. An intravascular catheter as in claim 1, wherein the
`distal tip has a shaft diameter, and wherein the Shaft diameter
`of the distal tip is less than the lateral profile of the distal tip.
`4. An intravascular catheter as in claim 1, wherein the
`distal tip is wave-shaped.
`5. An intravascular catheter as in claim 4, wherein the
`wave-shaped distal tip is two dimensional.
`6. An intravascular catheter as in claim 4, wherein the
`wave-shaped distal tip is three dimensional.
`7. An intravascular catheter as in claim 4, wherein the
`distal tip is Sinusoid-shaped.
`8. An intravascular catheter System for providing acceSS
`to a lumen of a coronary artery having an ostium, the System
`comprising:
`a catheter comprising an elongate Shaft having a proximal
`portion, a distal tip and a lumen extending
`therethrough, the distal tip having a lateral profile that
`is larger than the lumen of the coronary artery adjacent
`the ostium when the tip is in a relaxed State Such that
`the distal tip frictionally engages the coronary artery,
`the distal tip having a lateral profile that is Smaller than
`the lumen of the coronary artery adjacent the ostium
`when the tip is in a stressed State; and
`a guide wire disposed in the lumen of the Shaft, wherein
`the lateral profile of the distal tip decreases when the
`guide wire extends therethrough.
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`US 6,595,952 B2
`
`6
`9. A method of accessing a lumen of a coronary artery
`having an ostium, the method comprising the Steps of:
`providing an intravascular catheter comprising an elon
`gate Shaft having a proximal portion, a distal tip and a
`lumen extending therethrough, the distal tip having a
`lateral profile that is larger than the lumen of the
`coronary artery adjacent the ostium when the distal tip
`is in a relaxed State and a lateral profile that is Smaller
`than the lumen of the coronary artery adjacent the
`OStium when the tip is in a Stressed State, and
`inserting the distal tip into the ostium Such that the distal
`tip frictionally engages the coronary artery.
`10. A method as in claim 9, further comprising the steps
`of:
`providing a guide wire, and
`inserting the guide wire into the lumen of the Shaft and
`through the distal tip such that the lateral profile of the
`distal tip decreases.
`11. A method as in claim 10, wherein the step of inserting
`the guide wire to decrease the lateral profile of the distal tip
`is performed prior to the Step of inserting the distal tip into
`the ostium.
`12. A method as in claim 11, further comprising the Step
`of:
`retracting the guide wire from the distal tip Such that the
`lateral profile of the distal tip increases.
`13. A method as in claim 12, wherein the Step of retracting
`the guide wire from the distal tip such that the lateral profile
`increases is performed Subsequent to the Step of inserting the
`distal tip into the ostium.
`14. A method as in claim 13, further comprising the Steps
`of:
`providing an intravascular device; and
`inserting the intravascular device into the lumen of the
`catheter and into the lumen of the coronary artery.
`15. A method as in claim 14, further comprising the Steps
`of:
`advancing the intravascular device through the lumen of
`the coronary artery; and
`upon encountering resistance to advancement through the
`lumen of the coronary artery, applying additional push
`ing force to the intravascular device to cause the lateral
`profile of the distal tip of the catheter to increase and
`thereby further engage the coronary artery adjacent the
`OStium.
`
`Page 8
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`Medtronic Exhibit 1058
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