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`
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`Old’S’NSELOL
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`Customer No. 24113
`Patterson, Thuente, Skaar & Christensen, P.A.
`4800 IDS Center
`80 South 8th Street
`Minneapolis, Minnesota 55402-2100
`Telephone: (612) 349-5740
`Facsimile: (612) 349-9266
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`Attorney Docket No. 2005.86US01
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`APPLICATION TRANSMITTAL
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`0 o
`an
`aco
`5O=
`ew=
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`Nyr
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`Commissioner for Patents
`P.O. Box 1450
`Alexandria, VA 22313-1450
`
`Sir:
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`Transmitted herewith for filing under 37 C.F.R. § 1.53(b) is the patent application of
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`INVENTOR(S): Howard Root, Gregg Sutton; Jeffrey M. Welch, and Jason M. Garrity
`FOR: COAXIAL GUIDE CATHETER FOR INTERVENTIONAL CARDIOLOGY PROCEDURES
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`Enclosedare:
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`[X]
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`[X]
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`[
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`[
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`{
`{
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`[
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`Specification and Abstract - 29 pages.
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`Drawings - 13 sheets (Figs. 1-22).
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`Combined Declaration and Powerof Attorney.
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`Information Disclosure Statement.
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`CD-ROMor CD-R in duplicate, and Compact Disc Transmittal.
`Request and Certification Under 35 U.S.C. 122(b)(2)(B)() (nonpublication).
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`
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`Thefiling fee has been calculated as shown below:
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`.
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`Large Entity
`Small Entity
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`Rate
`Rate
`No. Extra
`No. Filed
`|BasicFilingFee|ISTOR8300S
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`|UtilitySearchFee|S250TOR8500
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`|UtilityExaminationFee[|S|OR8200
`[TotalClaims205=STORxSO=S
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`IndependeatClaims“3_—_—_])_/aims.ORfuames
`+[360|
`aaame[eeroe[as
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`that exceeds 100 sheets:
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`PoTOTALS500==TOTALS
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`**If the difference is less than zero, enter “OQ”. Total # of sheets = (Spec and Abst pgs)+Dwg Sheets
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`[X]
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`Applicant(s) is/are entitled to small entity status in accordance with 37 CFR 1.27.
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`IPR2020-00126/-127/-128/-129/-130/-132/-134/-135/-136/-137/-138
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`Medtronic Ex-1842
`Medtronic v. Teleflex
`Page 1
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`Page 1
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`IPR2020-00126/-127/-128/-129/-130/-132/-134/-135/-136/-137/-138
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`Medtronic Ex-1842
`Medtronic v. Teleflex
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`aS
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`Attorney Docket No. 2005.86US01
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`{
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`]
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`A check in the amount of $_0_ to coverthe filing fee is attached. The Commissioner is hereby
`authorized to grant any extensions of time and to charge any fees under 37 C.F.R. §§ 1.16 and
`1.17 that may be required during the entire pendency of this application to Deposit Account No.
`16-0631.
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`{
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`]
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`This application claims the benefit of U.S. Provisional Application No.
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`» filed
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`Respectfully submitted,
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`
`
`Paul C. Onderick
`Registration No. 45,354
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`CERTIFICATE OF EXPRESS MAIL
`
`I herebycertify that this paper is being
`“Express Mail” mailing label number EV824529593US. Date of Deposit: May 3, 2006.
`deposited with the United States Postal Service “Express Mail Post Office to Addressee” service under 37 C.F.R. § 1.10 on the
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`date indicated above and is addressed to the Commissionerfor Patentee. Alexandria, VA22313-1450.
`DRS LH7AOnKE
`Nameof Person Making Deposit
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`ae)
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`Signature
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`Page 2
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`Page 2
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`Attorney Docket No. 2005.86US01
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`Abstractof the Disclosure
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`A coaxial guide catheter to be passed through guide catheter having a first lumen,
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`for use with interventional cardiology devices that are insertable into a branch artery that
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`branches off from a main artery. The coaxial guide catheter is extended through the lumen ofthe
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`guide catheter and beyond the distal end of the guide catheter and inserted into the branch artery.
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`The device assists in resisting axial and shear forces exerted by an interventional cardiology
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`device passed through the second lumen and beyond the flexible distal tip portion that would
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`otherwise tend to dislodge the guide catheter from the branchartery.
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`Attorney Docket No. 2005.86US01
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`COAXIAL GUIDE CATHETER FOR INTERVENTIONAL CARDIOLOGY
`PROCEDURES
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`Field of the Invention
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`The present invention relates generally to catheters used in interventional
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`cardiology procedures. More particularly the present invention relates to methods and apparatus
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`for increasing backup support for catheters inserted into the coronary arteries from the aorta.
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`Background of the Invention
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`15
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`Interventional cardiology procedures often include inserting guidewires or other
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`instruments through catheters into coronary arteries that branch off from the aorta. For the
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`purposes of this application, the term "interventional cardiology devices" is to be understood to
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`include but not be limited to guidewires, balloon catheters, stents and stent catheters.
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`In
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`coronary artery disease the coronary arteries may be narrowed or occluded by atherosclerotic
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`20
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`plaques or other lesions. These lesions may totally obstruct the lumen of the artery or may
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`dramatically narrow the lumen of the artery. Narrowing is referred to as stenosis. In order to
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`diagnose and treat obstructive coronary artery disease it is commonly necessary to pass a
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`guidewire or other instruments through and beyond the occlusion or stenosis of the coronary
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`artery.
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`25
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`In treating a stenosis, a guide catheter is inserted through the aorta and into the
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`ostium of the coronary artery. This is sometimes accomplished with the aid of a guidewire. A
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`guide catheter is typically seated into the opening or ostium of the artery to be treated and a
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`guidewire or other instrument is passed through the lumen of the guide catheter and inserted into
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`the artery beyond the occlusion or stenosis. Crossing tough lesions can create enough backward
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`Attorney Docket No. 2005.86US01
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`force to dislodge the guide catheter from the ostium of the artery being treated. This can make it
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`difficult or impossible for the interventional cardiologist to treat certain forms of coronary artery
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`disease.
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`Prior attempts to provide support to the guiding catheter to prevent backward
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`dislodgement from the coronary ostium (referred to as "backup support") fall generally into four
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`categories.
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`First are guiding catheters that, through a combination of shape and stiffness, are
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`configured to draw backup support from engaging the wall of the aortic arch opposing the ostium
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`of the coronary artery that is being accessed. Examples of this approach can be found in U.S.
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`10
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`Patent No. 6,475,195 issued to Voda and U.S. Patent No. 5,658,263 issued to Dang et al. These
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`guiding catheters all share the common limitation that a guide catheter stiff enough to provide
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`adequate backup support is often too stiff to be safely inserted into the aorta without the
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`possibility of causing damage to the aortic wall.
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`In addition, attempts to deep seat the guide
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`catheter have been made but the rigid nature of the guide catheter creates the risk that the guide
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`15
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`catheter may damage the coronary artery wall or that the guide catheter may occlude the
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`coronary artery and interfere with blood flow to the heart muscle.
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`Second are guiding catheters that include a retractable appendage. The appendage
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`in these catheters can be extended to engage the opposing wall of the aortic arch to provide
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`backup support or the appendage may be placed under tension to stiffen a bend in the catheter to
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`20
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`provide backup support. Examples of this approach may be found in U.S. Patent Nos. 4,813, 930
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`Attorney Docket No. 2005.86US01
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`issued to Elliot; 5,098,412 issued to Shiu; and 6,860,876 issued to Chen. These guiding catheters
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`tend to be somewhat mechanically complex and have not been widely adopted by practitioners.
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`Third are guide catheters that have a portion that seeks to expand laterally to grip
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`the interior wall of the ostium of the coronary artery to provide a force acting in opposition to the
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`backward forces created when trying to maneuver a therapeutic device past a lesion or blockage
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`in the coronary artery. These devices can include a balloon secured to a guidewire or a catheter
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`or another device for expanding to grip the walls of the coronary artery from within. Examples
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`of this approach may be found in U.S. Patent Nos. 4,832,028 issued to Patel; 6,595,952 issued to
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`Forsberg; and U.S. Published Application No. 2005/0182437 by Bonnette et al. Again, these
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`10
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`devices tend to be mechanically complex and can completely occlude the coronary ostium thus
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`stopping perfusion of the coronary artery.
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`A fourth technique includes the placement of a smaller guide catheter within a
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`larger guide catheter in order to provide added support for the crossing of lesions or for the distal
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`delivery of balloons and stents. This technique has been described in an article by Takahashi
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`15
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`entitled "New Method to Increase a Backup Support of Six French Guiding Coronary Catheter,"
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`published in Catheterization and Cardiovascular Interventions, 63:452-456 (2004). This
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`technique is used in order to provide a method of deep seating the guide catheter within the
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`ostium of the coronary artery. Deep seating refers to inserting the catheter more deeply into the
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`ostium of the coronary artery than typically has been done before. Unfortunately, deep seating
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`by this technique with a commonly available guide catheter creates the risk that the relatively
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`stiff, fixed curve, guide catheter will damage the coronary artery. This damage may lead to
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`dissection of the coronary artery when the catheter is advanced past the ostium.
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`Several other problems arise when using a standard guide catheter in this catheter(cid:173)
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`in-a-catheter fashion. First, the inner catheters must be substantially longer than the one hundred
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`5
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`centimeter guide catheter. Second, a new hemostasis valve must be placed on the inner guide
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`catheter which prevents the larger guide catheter from being used for contrast injections or
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`pressure measurements. Third, the smaller guide catheter still must be inserted into the coronary
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`vessel with great care since the smaller guide catheter has no tapered transition or dilator at its tip
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`and does not run over a standard 0.014 inch guidewire.
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`10
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`Thus, the interventional cardiology art would benefit from the availability of a
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`system that would be deliverable through standard guide catheters for providing backup support
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`by providing the ability to effectively create deep seating in the ostium of the coronary artery.
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`Summary of the Invention
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`15
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`The present invention is a coaxial guide catheter that is deliverable through
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`standard guide catheters by utilizing a guidewire rail segment to permit delivery without
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`blocking use of the guide catheter. The coaxial guide catheter preferably includes a tapered inner
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`catheter that runs over a standard 0.014 inch coronary guidewire to allow atraumatic placement
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`within the coronary artery. This feature also allows removal of the tapered inner catheter after
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`the coaxial guide catheter is in place. The tapered inner catheter provides a gradual transition
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`Attorney Docket No. 2005.86US01
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`from the standard 0.014 inch diameter guidewire to the diameter of the coaxial guide catheter
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`which is typically five to eight French.
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`The coaxial guide catheter preferably can be delivered through commonly
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`existing hemostatic valves used with guide catheters while still allowing injections through the
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`5
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`existing Y adapter. In addition, the coaxial guide catheter preferably has an inner diameter that
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`is appropriate for delivering standard coronary treatment devices after it is placed in the coronary
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`artery.
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`In one embodiment, the coaxial guide catheter is made in at least three sizes
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`corresponding to the internal capacity of 8 French, 7 French, and 6 French guide catheters that
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`are commonly used in interventional cardiology procedures. An 8 French catheter has an
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`internal diameter greater than or equal to 0.088 inches. A 7 French catheter has an internal
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`diameter greater than or equal to 0.078 inches. A 6 French guide catheter has an internal
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`diameter greater than or equal to 0.070 inches. Thus, for three exemplary sizes the effective
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`internal diameter of the coaxial guide catheter may be as follows. For a 7 French in 8 French
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`15
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`coaxial guide catheter the internal diameter should be greater than or equal to 0.078 inches. For
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`a 6 French in 7 French coaxial guide catheter the internal diameter should be greater than or
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`equal to 0.070 inches. For a 5 French in 6 French coaxial guide catheter the internal diameter
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`should be greater than or equal to 0.056 inches.
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`Interventional cardiology procedures are typically carried out under fluoroscopy
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`20
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`or another x-ray or imaging technique. Therefore, one embodiment of the coaxial guide catheter
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`of the present invention includes a radiopaque marker at its distal tip to facilitate positioning and
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`manipulation of the coaxial guide catheter.
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`The present invention generally includes the coaxial guide catheter and a tapered
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`inner catheter. The coaxial guide catheter includes a tip portion, a reinforced portion, and a
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`substantially rigid portion. The coaxial guide catheter will generally have an overall length of
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`preferably approximately 125 cm, though this should not be considered limiting.
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`In one embodiment, the tip portion may include a soft tip and a marker band. The
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`soft tip is tapered and may be formed from a low durometer polymer or elastomer material such
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`as polyether block amide polymer, (PEBA, Pebax®) the marker band may be formed from a
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`platinum iridium alloy sandwiched between the Pebax® that extends from the bump tip and a
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`PTFE liner.
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`In one embodiment, the reinforced portion may be reinforced, preferably with
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`metallic fibers in a braided or coiled pattern. The braided or coiled portion is lined by a PTFE
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`liner and may be covered on its exterior with Pebax®. The braided or coiled portion may extend
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`15
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`approximately 20 to 110 cm in length.
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`In one exemplary embodiment, the braided portion
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`extends approximately 32 to 36 cm.
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`Preferably, the rigid portion may be advantageously formed from a stainless steel
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`or Nitinol tube. The rigid portion may be joined to the braid or coil portion by welding. The
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`rigid portion may include a cutout portion and a full circumference portion. For example, the
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`cutout portion may include a section where about 45% of the circumference of the cylindrical
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`tubular structure has been removed. The cutout portion may also include a section where 75-
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`Attorney Docket No. 2005.86US01
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`90% of the circumference of the tubular structure has been removed.
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`In one exemplary
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`embodiment, the portion having approximately 45% removed may extend for approximately 75
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`cm and the portion having 75-90% of the structure removed extends for about 15 cm. The full
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`circumference portion of the rigid portion is typically located at the most proximal end of the
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`coaxial guide catheter.
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`The rigid portion may include a plurality of radially oriented slits or other cuts in
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`its distal portion to increase and control the flexibility of the rigid portion
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`In an exemplary embodiment, the tapered inner catheter generally includes a
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`tapered inner catheter tip and a cutout portion. The tapered inner catheter tip includes a tapered
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`portion and a straight portion. The tapered portion is typically at the most distal end of the
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`tapered inner catheter. Both the straight portion and the tapered portion are pierced by a lumen
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`through which a guidewire may be passed.
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`The cutout portion supports a track passing along the concave side thereof that
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`continues from the lumen that passes through the straight portion and the tapered portion. The
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`tapered inner catheter may also have a clip or snap attachment at its proximal end to releasably
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`join the tapered inner catheter to the coaxial guide catheter.
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`In operation, the tapered inner catheter is inserted inside and through the coaxial
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`guide catheter. The tapered inner catheter is positioned so that the tapered inner catheter tip
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`extends beyond the tip portion of the coaxial guide catheter. The coaxial guide catheter-tapered
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`inner catheter combination may then be inserted into a blood vessel that communicates with the
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`aorta. The coaxial guide catheter-tapered inner catheter combination may be threaded over a
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`Attorney Docket No. 2005.86US01
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`preplaced 0.014 inch guidewire. The tapered inner catheter-coaxial guide catheter combination
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`is advanced up the aorta until the tapered inner catheter is passed into the ostium of a coronary
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`artery over the guidewire. Once the coaxial guide catheter-tapered inner catheter combination
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`has been inserted sufficiently into the ostium of the coronary artery to achieve deep seating the
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`tapered inner catheter may be removed. During this entire process at least part of the coaxial
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`guide catheter-tapered inner catheter combination is located inside of the guide catheter.
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`Once the tapered inner catheter is removed a cardiac treatment device, such as a
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`guidewire, balloon or stent, may be passed through the coaxial guide catheter within the guide
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`catheter and into the coronary artery. As described below, the presence of the coaxial guide
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`catheter provides additional backup support to make it less likely that the coaxial guide catheter
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`guide catheter combination will be dislodged from the ostium of the coronary artery while
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`directing the coronary therapeutic device past a tough lesion such as a stenosis or a chronic
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`arterial occlusion.
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`A guide catheter inserted into the ostium of a branch artery where it branches off
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`15
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`from a larger artery is subject to force vectors that tend to dislodge the distal end of the guide
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`catheter from the ostium of the branch artery when a physician attempts to direct a guidewire or
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`other interventional cardiology device past an occlusive or stenotic lesion in the branch artery.
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`This discussion will refer to a guide wire but it is to be understood that similar principles apply to
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`other interventional cardiology devices including balloon catheters and stent catheters.
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`One of the forces that acts on the guide catheter is an axial force substantially
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`along the axis of the branch artery and the portion of the guide catheter that is seated in the
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`Attorney Docket No. 2005.86US01
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`ostium. This force vector is a reactive force created by the pushing back of the guide wire
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`against the guide catheter as the physician tries to force the guidewire through or past the lesion.
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`It tends to push the distal end of the catheter out of the ostium in a direction parallel to the axis of
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`the branch artery and the axis of the distal end of the guide catheter.
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`5
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`Another of the force vectors that acts on the guide catheter is a shearing force that
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`tends to dislodge the distal end of the guide catheter from the ostium of the branch artery in a
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`direction perpendicular to the axis of the branch artery and the axis of the distal end of the guide
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`catheter. This force vector arises from curvature of the guide catheter near its distal end and the
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`guide wire pushing on the curved portion of the guide catheter as the physician applies force to
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`10
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`the guidewire. The coaxial guide catheter of the present invention assists in resisting both the
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`axial forces and the shearing forces that tend to dislodge a guide catheter from the ostium of a
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`branch artery.
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`The system is deliverable using standard techniques utilizing currently available
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`equipment. The present invention also allows atraumatic placement within the coronary artery:
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`15
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`Further, the invention is deliverable through an existing hemostatic valve arrangement on a guide
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`catheter without preventing injections through existing Y adapters. Finally, the invention has an
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`inner diameter acceptable for delivering standard coronary devices after it is placed in the blood
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`vessel.
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`Brief Description of the Drawings
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`Page 12
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`Attorney Docket No. 2005.86US01
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`Fig. 1 is a schematic depiction of the coaxial guide catheter and a tapered inner
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`catheter in accordance with the present invention;
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`Fig. 2 is schematic depiction of the coaxial guide catheter and tapered inner
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`catheter assembled in accordance with the present invention;
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`5
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`Fig. 3 is a plan view of a guide catheter, the coaxial guide catheter, and a
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`treatment catheter in accordance with the present invention;
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`Fig. 4 is a sectional view of the coaxial guide catheter in accordance with the
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`present invention;
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`Fig. 5 is a cross sectional view of the coaxial guide catheter and tapered inner
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`10
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`catheter in accordance with the present invention;
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`Fig. 6 is another cross sectional view of the coaxial guide catheter and tapered
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`inner catheter in accordance with the present invention;
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`Fig. 7 is a schematic view of a guide catheter and a guidewire located in an aortic
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`arch and a coronary artery and the guide catheter and guidewire in a second position depicted in
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`15
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`phantom;
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`Fig. 8 is a schematic view of a guide catheter, a guidewire, a coaxial guide
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`catheter in accordance with the present invention and a tapered inner catheter located in the
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`aortic arch and coronary artery;
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`Fig. 9 is a schematic view of a guide catheter, a guidewire and a coaxial guide
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`20
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`catheter in accordance with the present invention located in the aortic arch and coronary artery;
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`Attorney Docket No. 2005.86US01
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`Fig. 10 is a flat pattern for making relief cuts in a curved rigid portion of the
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`coaxial guide catheter in accordance with the present invention;
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`Fig. 11 is a detailed view taken from Fig. 1 O;
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`Fig. 12 is a plan view of the rigid portion in accordance with the present
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`5
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`invention;
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`Fig. 13; and
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`10
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`Fig. 13.
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`Fig. 13.
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`Fig. 13 is an elevational view of the rigid portion;
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`Fig. 14 is a sectional view of the rigid portion taken along section line 14-14 of
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`Fig. 15 is a sectional view of the rigid portion taken along section line 15-15 of
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`Fig. 16 is a sectional view of the rigid portion taken along section line 16-16 of
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`Fig. 17 is a plan view of a coaxial guide catheter having a longer rail segment and
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`a tapered inner catheter in accordance with the present invention.
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`15
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`Fig. 18 is a plan view of the tapered inner catheter as depicted in the Fig. 17.
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`Fig. 19 is a cross-sectional view of the tapered inner catheter taken along section
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`lines 19-19 of Fig. 18.
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`Fig. 20 is a plan view of a coaxial guide catheter in accordance with the present
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`invention.
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`20
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`Fig. 21 is an elevational view of a coaxial guide catheter in accordance with the
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`present invention.
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`Attorney Docket No. 2005.86US01
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`Fig. 22 is a cross-sectional view taken along section line 22-22 of Fig. 21.
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`Detailed Description of the Invention
`
`5
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`Referring to Figs. 1 and 2, coaxial guide catheter assembly 10 of the present
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`invention generally includes coaxial guide catheter 12 and tapered inner catheter 14.
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`Coaxial guide catheter 12 generally includes tip portion 16, reinforced portion 18,
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`and rigid portion 20. The overall length of the coaxial guide catheter typically can be
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`approximately 125 cm. This length should not be considered limiting.
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`10
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`Tip portion 16 generally includes bump tip 22 and marker band 24. Bump tip 22
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`includes taper 26. Bump tip 24 is relatively flexible and may be formed, for example, from 4033
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`Pebax®. Bump tip 22 may be yellow or another high visibility color for ease of handling.
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`Marker band 24 is formed of a radiopaque material such as platinum/iridium alloy
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`usually at a 90/10 ratio. Marker band 24 may be sandwiched between an outer Pebax® material
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`15
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`28 and a PTFE liner 30. Outer Pebax® material 28 in this location may be formed of 5533
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`Pebax, for example.
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`Reinforced portion 18 includes braid or coil reinforcement 32. Braid or coil
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`reinforcement 32 may be formed of metal, plastic, graphite, or composite structures known to the
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`art. Reinforced portion 18 may be lined on the interior by PTFE liner 30 and covered on the
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`20
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`exterior by Pebax® material 28. Tip portion 16 and reinforced portion 18 together form a
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`substantially cylindrical structure. Braid or coil reinforcement 32 may extend approximately 20
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`Attorney Docket No. 2005.86US01
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`to 30 cm. In one exemplary embodiment, braid or coiled portion has a length of approximately
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`32 to 36 cm.
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`Rigid portion 20 may be secured to braid or coil reinforcement by, for example,
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`welding or bonding. Rigid portion 20 may be formed from a hypotube or a section of stainless
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`5
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`steel or Nitinol tubing. Other substantially rigid materials may be used as well. Rigid portion 20
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`includes first full circumference portion 34, hemicylindrical portion 36, arcuate portion 38, and
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`second full circumference portion 40.
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`First full circumference portion 34 is joined to braid or coil reinforcement 32.
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`First full circumference portion 34 extends for a relatively short distance, for example, .25 cm.
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`10
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`Hemicylindrical portion 36 desirably includes 40% to 70% of the circumference
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`of the tube. Hemicylindrical portion 36 may extend, for example, approximately 20 to75 cm in
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`length.
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`Hemicylindrical portion 36 tapers into arcuate portion 38.
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`Arcuate portion 38 extends from 25% to 40% of the circumference of the tube.
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`15 Arcuate portion 3 8 may extend linearly, for example, for about 15 cm.
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`Arcuate portion 38 connects to second full circumference portion 40. Second full
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`circumference portion 40 may extend for a short distance, for example, approximately 3 cm.
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`Tapered inner catheter 14 generally includes tapered inner catheter tip 42 and
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`cutout portion 44. Tapered inner catheter tip 42 tapers gradually from the diameter of a guide
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`20 wire to the diameter oftip portion 16.
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`Attorney Docket No. 2005.86US01
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`Tapered inner catheter tip 42 includes tapered portion 46 at a distal end thereof,
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`and straight portion 48. Both tapered portion 46 and straight portion 48 are pierced by lumen 50.
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`Cutout portion 44 defines a concave track 52 along its length. Concave track 52
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`is continuous with lumen 50.
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`5
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`Tapered inner catheter 14 may also include clip 54 at a proximal end thereof to
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`releasably join tapered inner catheter 14 to coaxial guide catheter 12. Thus, tapered inner
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`catheter 14 is keyed to coaxial guide catheter 12.
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`Coaxial guide catheter 12 may include, starting at its distal end, a first portion
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`having a flexural modulus of about 13,000 PSI plus or minus 5000 PSI, a second portion having
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`10
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`a flexural modulus of about 29,000 PSI plus or minus 10,000 PSI, a third portion having a
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`flexural modulus of about 49,000 PSI plus or minus 10,000 PSI and a fourth portion having a
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`flexural modulus of about 107,000 PSI plus or minus 20,000 PSI. Coaxial guide catheter 12 may
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`be formed, for example, of 4033 Pebax ® at bump tip 22 for the first 0.1 cm. This portion may
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`followed by a section about three cm long of 5533 Pebax® that covers marker band 24 and the
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`distal portion of braid or coil reinforcement 32. Next may come an approximately five cm
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`portion of 6333 Pebax® which encloses part of braid or coil reinforcement 32 followed by an
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`approximately twenty seven cm portion of 7233 Pebax® covering the most proximal portion of
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`braid or coil reinforcement 32. Braid or coil reinforcement 32 is bonded to rigid portion 20
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`which may be formed from stainless steel or a similar biocompatible material. Rigid portion 20
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`20 may extend for approximately ninety cm and include first full circumference portion 34
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`(approximately .25 cm), hemicylindrical portion 36 (approximately seventy five cm), arcuate
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`Attorney Docket No. 2005.86US01
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`portion (approximately fifteen cm) and second full circumference portion (approximately three
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`cm.) Rigid portion 20 may be formed from a stainless steel or Nitinol hypo tube.
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`Fig. 7 depicts a typical guide catheter 56 passing through aortic arch 58 into
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`ostium 60 of coronary artery 62. Fig. 7 also depicts guidewire 64 passing through the guide
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`5
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`catheter 56 and into coronary artery 62. Located in coronary artery 62 is stenotic lesion 66. In a
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`typical procedure, guidewire 64 is placed through the aortic arch 58 and into the ostium 60 of the
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`coronary artery. 62. The guide catheter 56 is passed over guidewire 64 until distal end 68 of
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`guide catheter 56 is seated in ostium 60 of coronary artery 62. Force is then applied to the
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`guidewire 64 to push guidewire 64 past stenotic lesion 66 or an occlusive lesion (not shown).
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`10 Once the guidewire 64 is pushed past stenotic lesion 66 or occlusive lesion (not shown), a
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`treating catheter including a stent or balloon can be passed along the guidewire to stenotic lesion
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`66 or occlusive lesion (not shown). The lesion can then be treated.
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`As can be seen in phantom, in Fig. 7, the application of force to guidewire 64 can
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`cause guide catheter 56 to dislodge from ostium 60 of coronary artery 62. This can occur in the
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`15
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`case of a tough stenotic lesion 66 or occlusive lesion (not shown) when it is difficult to pass the
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`guidewire 64 beyond the stenotic lesion 66 or occlusive lesion (not shown).
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`Referring the Fig. 8 coaxial guide catheter 12 is depicted as used with guide
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`catheter 56, guidewire 64, and tapered inner catheter 14. Here, coaxial guide catheter 12 with
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`tapered inner catheter 14 is passed through guide catheter 56 and over guidewire 64 into
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`20
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`coronary artery 62 after the guide catheter 56 has been placed in the ostium 60 of coronary artery
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`62, as depicted in Fig. 7. Coaxial guide catheter 12, with tapered inner catheter 14, provide an
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`Attorney Docket No. 2005.86US01
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`inner support member for proper translation over guidewire 64. Tapered inner catheter tip 42
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`provides a distal tapered transition from guidewire 64 to coaxial guide catheter 12. Once coaxial
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`guide catheter 12 is in place, tapered inner catheter 14 is removed from the inside of coaxial
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`guide catheter 12.
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`5
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`Coaxial guide catheter 12 is now ready to accept a treatment catheter such as a
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`stent or balloon catheter. Referring to Fig. 9, the combination of guide catheter 56 with coaxial
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`guide catheter 12 inserted into ostium 60 of coronary artery 62 provides improved distal
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`anchoring of guide catheter 56 and coaxial guide catheter 12. The presence of coaxial guide
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`catheter 12 within guide catheter 56 also provides stiffer back up support than guide catheter 56
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`10
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`alone. The combination of improved distal anchoring and stiffening of the guide catheter
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`56/coaxial guide catheter 12 combination provides additional back up support to resist dislodging
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`of guide catheter 56 from ostium 60 when force is applied to guidewire 64 to pass through
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`stenotic lesion 66 or another lesion. In addition, the improved back up support assists in the
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`positioning of a treating catheter that may include a stent or balloon.
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`15
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`Referring to Figs. 10 and 11, in some embodiments of coaxial guide catheter 12,
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`rigid portion 20 may be perforated by relief cuts 70. Relief cuts 70 may be classed into first
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`group 72 and second group 74.
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`First group 72 may be located near to the juncture between rigid portion 20 and
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`reinforced portion 18. First group 72 of relief cuts 70 are relatively closely spaced. For
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`20
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`example, first group 72 of relief cuts 70 may be spaced approximately .010 inches apart. First
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`Attorney Docket No. 2005.86US01
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`group 72 of relief cuts 70 extends for a relatively short distance, for example, approximately 2
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`inches.
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`Second group 74 of relief cuts 70 may extend for a relatively long distance, for
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`example, approximately 30-35 inches. Second group 74 of relief cuts 70 are spaced farther apart
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`5
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`than first group 72.
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`For example, relief cuts 70 of second group 74 may be spaced
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`approximately .020 inches between cuts. Referring particularly to Fig. 11, relief cuts 70 may
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`include single cuts 76 and double cuts 78. Single cuts 76 may include an individual linear cut, as
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`can be seen in Fig. 11. Double cuts 78 may include two linear cuts along a single line but
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`separated by a short section of uncut structure. Typically, single cuts 76 and double cuts 78 are
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`10
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`alternated along the length of rigid portion 20. Generally, the overall length of single cut 76 may
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`be less than the overall length of two double cuts 78.
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`In an embodiment depicted
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`in Figs. 12-15, rigid portion
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`includes full
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`circumference portion 80, greater than 180° portion 82, and less than 180° portion 84. Greater
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`than 180° portion 82 may, for example, include structure forming approximately 300° of the
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`15
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`circumference of the cylinder. Less than 180° portion may include, fo