Temporary stent system

• US 6,371,953 B1
• Filed: 04/18/2000
• Issued: 04/16/2002
• Est. Priority Date: 03/30/1993
• Status: Expired due to Term

• Current Assignee: Ev3 Peripheral Inc. (Medtronic Plc)
• Original Assignee: Intratherapeutics Incorporated (Sulzer Medica)
• Inventors: Beyar, Mordechay, Globerman, Oren, Beyar, Rafael
• Primary Examiner(s): Chaudhuri, Olik
• Assistant Examiner(s): Trinh, (Vikki) Hoa B.
• Application Number:
  US09/551,479
• Time in Patent Office: 728 Days
• Field of Search: 606/194, 606/108, 606/110, 606/113-114, 606/191, 606/195, 606/198, 623/1--
• US Class Current: 623/1.1
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/9505 having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument
• CPC Class Codes: A61F 2002/9511 the retaining means being filaments or wires
• CPC Class Codes: A61F 2250/0059 temporary

Abstract

This application is directed to a stent delivery system for introducing a flexible, generally cylindrical, self-expandable stent. The system comprises a catheter having distal and proximal ends, the catheter defining at least one lumen extending therethrough and having at least three longitudinally displaced openings or sets of openings extending from a lumen to the surface of the catheter; a stent which comprises a generally cylindrical, expandable structure having proximal and distal ends and a flexible member extending proximally from the proximal end of the structure, the stent being wound circumferentially around the catheter, and having restraining means holding each of the proximal and distal ends of the stent to the catheter, and one or more restraining means holding at least a portion of the flexible member to the catheter surface; and one or two release wires positioned in and extending longitudinally through at least one lumen, the release wires cooperating with the restraining means so that as the release wire or wires are withdrawn proximally, the proximal and distal end sections of the stent are released in such a manner that coils of the stent unwind.

Claims

1. A stent delivery system comprising:

a catheter having distal and proximal ends, said catheter defining at least one lumen extending therethrough and having two longitudinally displaced openings extending from the at least one lumen to an outer surface of the catheter;

a self expanding coil stent mounted on the outer surface of said catheter, said stent having proximal and distal ends, said stent having a mounted configuration with a first region having coils separated by a first spacing and a second region having coils separated by a second spacing, the first spacing being smaller than the second spacing;

restraining members structurally distinct from said stent and holding each of the proximal and distal ends of the stent to the catheter;

at least one release wire positioned in and extending longitudinally through the at least one lumen, wherein said restraining members extend through the longitudinally displaced openings to hold both ends of the stent, so that as the at least one release wire is withdrawn proximally, the coils of the stent self-unwind; and

said catheter defining one or more grooves positioned between the longitudinally displaced openings for retaining said stent in the mounted configuration with the first spacing at the first region and the larger second spacing at the second region.

2. The system of claim 1, wherein the at least one lumen defined by the catheter comprises a central lumen and one or more side lumens having the longitudinally displaced openings or sets of openings extending to the outer surface of the catheter.

3. The system of claim 1, wherein each restraining member comprises a loop member having an opening therein.

4. The system of claim 3, wherein each loop member is positioned across an external surface of the stent.

5. The system of claim 3, wherein each loop member cooperates with the at least one release wire.

6. The system of claim 3, wherein the loop member is comprised of a bioabsorbable material.

7. The system of claim 6, wherein when the at least one release wire is pulled proximally each loop member disengages from the release wire or wires to release the stent, and the stent uncoils.

8. The system of claim 1, wherein the stent is comprised of superelastic shape memory alloy, a shape memory polymer, or a bioabsorbable polymer.

9. The system of claim 1, wherein the stent has an anti-thrombotic coating.

10. The system of claim 9, wherein the antithrombotic coating comprises an effective amount of low molecular weight heparin.

11. The system of claim 1, wherein the catheter has a section of reduced external diameter substantially coextensive with the stent.

12. The system of claim 1, wherein the coils of the stent unwind such that a middle section of the released stent is in substantially the same position as middle section of the unreleased stent.

13. The system of claim 1, wherein the coils of the stent are more closely wound adjacent the distal end than adjacent the proximal end.

14. The system of claim 1, wherein a distal portion of the catheter and a distal portion of the at least one release wire are more flexible than respective proximal portions of the catheter and the at least one release wire.

18. The stent delivery system of claim 1, wherein the one or more grooves have a configuration with a first region having grooves separated by a first spacing and a second region having grooves separated by a second spacing, the first spacing being smaller than the second spacing, wherein the first and second spacings of the grooves correspond to the first and second spacings of the coils.

15. A stent delivery system comprising:

a catheter having distal and proximal ends, the catheter including a stent mounting location positioned adjacent the distal end;

a self expanding coil stent mounted at the stent mounting location of the catheter, the stent having proximal and distal ends, the stent including a first region having coils separated by a first spacing and a second region having coils separated by a second spacing, the first spacing being smaller than the second spacing;

the stent being secured to the catheter at connection locations located adjacent the proximal and distal ends of the stent;

at lease one release member positioned in and extending longitudinally through the catheter for releasing the stent such that the coils of the stent self-unwind; and

the catheter including one or more coil-spacers defined at an outer surface of the catheter at the stent mounting location, the coil-spacers being configured for preventing the stent from self-adjusting to a configuration with uniform spacing between the coils of the first and second regions when the stent is mounted at the stent mounting location, and wherein the one or more coil-spacers includes one or more grooves.

16. The stent delivery system of claim 15, wherein the first region is located adjacent the distal end of the stent.

17. The stent delivery system of claim 15, wherein the one or more coil-spacers engage the coils of both the first and second regions of the stent.