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

摘要

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.