United States Patent m
Fischell et al.
 STENT DELIVERY CATHETER SYSTEM
 Inventors: Robert E. Fischell, Dayton, Md.;
David R. Fischell. Fair Haven, N.J.;
Urn A. Fischell. Richland, Mich.
 Assignee: Cathco, Inc.. Dayton. Md.
 Appl. No.: 828,662
 Filed: Mar. 31, 1997
 Int CI.6 A61M 29/00
 U.S. CI 606/108; 606/194
 Field of Search 606/108. 194,
606/198. 192. 195; 623/1. 12
 References Cited
U.S. PATENT DOCUMENTS
4,768,507 9/1988 Fischell et al 128/303 R
4,969,890 11/1990 Sugitaetal 606/192
5,192,297 3/1993 Hull 606/195
5,344,426 9/1994 Lau et al 606/198
5,639,274 6/1997 Fischell et al. .
FOREIGN PATENT DOCUMENTS 2102019 10/1992 Canada.
US005792144A [ii] Patent Number: 5,792,144  Date of Patent: Aug. 11, 1998
2111496 12/1992 Canada.
Primary Examiner—Michael Buiz
Assistant Examiner—Kevin Truong
The present invention is a stent delivery catheter system for placing a stent within a stenosis in a vessel of a human body. The stent delivery catheter system utilizes a slideable sheath with a thin-walled distal portion mat is situated coaxially over a stent that is placed onto a balloon located at the distal portion of a balloon angioplasty catheter. The distal end of a central portion of the sheath has an interior shoulder which is capable of exerting a distally directed push force on the balloon angioplasty catheter at a point that is just proximal to the stent This push force is then transferred through the non-deployed stent to a gradually tapered, highly flexible, lubricity coated distal tip of the balloon angioplasty catheter. The structure of a continuous outer surface extending backward from the distal tip and onto the distal section of the sheath, plus the lubricity coating of the outer surfaces of the distal tip and the sheath, plus the increased stent delivery catheter system pushability provided by the sheath and the stent itself makes it possible for the stent delivery catheter system to be pushed through even very tight stenoses.
15 Claims, 5 Drawing Sheets