Balloon angioplasty catheter with enhanced capability to penetrate a tight arterial stenosis

• US 5,830,227 A
• Filed: 04/16/1997
• Issued: 11/03/1998
• Est. Priority Date: 04/16/1997
• Status: Expired due to Term

• Current Assignee: Cardinal Health Switzerland 515 GmbH (Cardinal Health, Inc.)
• Original Assignee: Isostent, Inc. (Cardinal Health, Inc.)
• Inventors: Fischell, David R., Fischell, Robert E., Fischell, Tim A.
• Primary Examiner(s): MCDERMOTT, CORRINE MARIE
• Application Number:
  US08/840,788
• Time in Patent Office: 566 Days
• Field of Search: 604/96, 604/102, 606/108, 606/192, 606/194
• US Class Current: 606/194
• CPC Class Codes: A61M 2025/0183 Rapid exchange or monorail catheters
• CPC Class Codes: A61M 2025/1004 Balloons with folds, e.g. folded or multifolded
• CPC Class Codes: A61M 2025/1056 having guide wire lumens outside the main shaft, i.e. the guide wire lumen is within or on the surface of the balloon
• CPC Class Codes: A61M 2025/1093 having particular tip characteristics
• CPC Class Codes: A61M 2029/025 characterised by the guiding element
• CPC Class Codes: A61M 25/0068 Static characteristics of the catheter tip, e.g. shape, atraumatic tip, curved tip or tip structure
• CPC Class Codes: A61M 25/008 Strength or flexibility characteristics of the catheter tip
• CPC Class Codes: A61M 25/104 used for angioplasty

Abstract

The present invention is a balloon angioplasty catheter that combines a catheter shaft having increased pushability with an elongated, gradually tapered, highly flexible, lubricity coated, distal tip that is specifically designed to penetrate through a tight stenosis. The distal end of the tip is formed as a very thin-walled, tapered, frustrum of a cone that is capable of following a guide wire through even the most tortuous coronary arteries. The proximal end of the tip has a diameter that is equal to or slightly larger than the diameter of an angioplasty balloon that is wrapped around a catheter shaft at a distal section of the balloon angioplasty catheter. One embodiment of the invention includes a thin-walled tube located at the proximal end of the distal tip which extends over the distal end of the angioplasty balloon. This design can prevent the distal end of the wrapped pre-deployed balloon from engaging the arterial wall as it is pushed through a tight stenosis. The balloon angioplasty catheter can be designed with the capability for either or both a rapid exchange or over-the-wire mode.

Claims

1. A balloon angioplasty catheter system for the dilation of an arterial stenosis in a human subject, the balloon angioplasty catheter system comprising:

a flexible guide wire,

a balloon angioplasty catheter having a single elongated hollow cylindrical shaft which has a single lumen, the shaft having a proximal end and a distal end, the shaft extending for most of the length of the balloon angioplasty catheter, the balloon angioplasty catheter having a proximal end that is placed outside of the body of the human subject and having a distal section at which distal section an uninflated balloon is fixedly attached to the shaft, the balloon having a proximal end and a distal end and having a blunt distal fold located just proximal to the balloon'"'"'s distal end; and

an elongated gradually tapered distal tip in the general form of a frustrum of a cone having a continuous outer surface, the frustrum of the cone extending throughout the distal end of the balloon angioplasty catheter, the cone having its smallest diameter at the distal end of the distal tip, the distal tip having a proximal end that is situated immediately adjacent to the blunt distal fold of the uninflated balloon, the tip also being directly and fixedly attached to the distal end of the uninflated balloon, and the distal tip also having a distal end and a guide wire lumen having the guide wire placed slideably therein, the guide wire lumen extending in a proximal direction from the tip'"'"'s distal end, the tip also having a guide wire distal exit port at the tip'"'"'s distal end through which the guide wire exits from the balloon angioplasty catheter.

2. The balloon angioplasty catheter system of claim 1 wherein the diameter of the distal tip at its proximal end is equal to or larger than the diameter of the uninflated balloon.

3. The balloon angioplasty catheter system of claim 1 wherein the distal tip includes a thin-walled cylindrical section that extends from the proximal end of the distal tip over the blunt distal fold of the uninflated balloon.

4. The balloon angioplasty catheter system of claim 1 wherein the distal tip includes a proximal exit port placed distal to the balloon through which the guide wire can exit from the distal tip thus providing a rapid exchange capability for the balloon angioplasty catheter.

5. The balloon angioplasty catheter system of claim 1 wherein there are two radiopaque marker bands placed coaxially around the shaft of the balloon angioplasty catheter, the two radiopaque marker bands consisting of a proximal radiopaque marker band being located near the proximal end of the balloon and a distal radiopaque marker band being located near the distal end of the balloon.

6. The balloon angioplasty catheter system of claim 1 wherein the average slope angle of the continuous outer surface is less than 3 degrees.

7. The balloon angioplasty catheter system of claim 1 wherein the average slope angle of the continuous outer surface is less than 1.0 degree.