Variable stiffness balloon catheter

• US 6,322,534 B1
• Filed: 10/08/1999
• Issued: 11/27/2001
• Est. Priority Date: 11/07/1998
• Status: Expired due to Term

• Current Assignee: Codman & Shurtleff Incorporated (Johnson & Johnson)
• Original Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Inventors: Shkolnik, Boris
• Primary Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US09/415,532
• Time in Patent Office: 781 Days
• Field of Search: 604/96.01, 604/97, 604/99, 604/103, 604/104, 604/264, 606/191-194
• US Class Current: 604/96.01
• CPC Class Codes: A61M 25/005 with embedded materials for reinforcement, e.g. wires, coils, braids
• CPC Class Codes: A61M 25/0053 having a variable stiffness along the longitudinal axis, e.g. by varying the pitch of the coil or braid
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 25/104 used for angioplasty

Abstract

An improved balloon catheter which may be used for angioplasty or for placing a reinforcing stent into a human vessel which has a variable stiffness catheter portion for guiding the catheter through the vasculature. The catheter portion of the balloon catheter includes a relatively stiff shaft portion which is reinforced with braided layer and more flexible distal portion which is reinforced with a single helically wire coil so that the relatively stiff shaft portion may be advanced along a guidewire and the more flexible distal portion may be guided through the tortuous vasculature.

Claims

1. A balloon catheter comprising:

an inner catheter body having proximal and distal ends and comprising;

an inner tubular member having proximal and distal ends and a lumen extending therethrough;

a braided reinforcing layer disposed over the inner tubular member and extending from the proximal end of the inner tubular member and terminating at its distal end at a distance in a range of between about 50 and 70 centimeters from the distal end of the inner tubular member, said braided reinforcing layer formed of circular cross-section wire;

a coil reinforcing layer comprised of a single metallic wire of a circular cross-section formed in helical configuration disposed over the inner tubular member and extending from the distal end of the braided layer to about the distal end of the inner tubular member;

a thin outer layer formed over the braided reinforcing layer and the coil reinforcing layer and extending from the proximal end to the distal end of the inner tubular member;

an outer tubular member extending coaxially over the inner tubular member to form an inflation lumen between the outer and inner tubular members and having a proximal end and a distal end which terminates proximally from the distal end of the inner tubular member, said outer tubular member including a proximal portion formed of a material having a durometer of about 75 D and a distal portion formed of a material having a durometer of about 65 D;

an inflatable balloon having a main body portion and proximal and distal portions extending from the main body portion, said proximal portion of the balloon sealed to the distal end of the outer tubular member and said distal portion of the balloon being sealed to the distal end of the inner tubular member; and

a coupling member having a lumen extending therethrough, said coupling member being mounted on the proximal end of the outer tubular member and the lumen of the coupling member communicating with the lumen between the outer tubular member and the inner tubular member so that fluid may be injected into the lumen of the coupling member to inflate the balloon.

2. A balloon catheter as defined in claim 1, wherein the braided reinforcing layer is comprised of braided stainless steel wires wrapped onto the inner tubular member.

3. A balloon catheter as defined in claim 2, wherein the coil reinforcing layer is comprised of a single platinum wire of circular cross-section which is helically wrapped around the inner tubular member.

4. A balloon catheter as defined in claim 1, wherein the proximal portion of the outer tubular member is comprised of nylon and a distal portion of the outer tubular member is comprised of polyurethane and in which the distal portion of the outer tubular member has an outer diameter less than the outer diameter of the proximal portion of the outer tubular member.

5. A balloon catheter as defined in claim 5, wherein the distal portion of the outer tubular member has an inner diameter less than the inner diameter of the proximal portion of the outer tubular member.