Stent deployment catheter with retractable sheath

• US 5,772,669 A
• Filed: 09/27/1996
• Issued: 06/30/1998
• Est. Priority Date: 09/27/1996
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Vrba, Anthony C.
• Primary Examiner(s): Hafer, Robert A.
• Assistant Examiner(s): YU, JUSTINE ROMANG
• Application Number:
  US08/722,834
• Time in Patent Office: 641 Days
• Field of Search: 606/108, 606/195, 606/198, 606/194, 623/1, 623/12, 604/96
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod

Abstract

The present invention provides an improved stent delivery catheter. The stent delivery systems comprises a catheter having a stent receiving portion adapted to receive a stent near the distal end of the catheter and a stent concentrically arranged around the catheter within the stent receiving portion. The stent delivery system further comprises a proximal outer sheath, a retractable distal sheath surrounding at least a portion of the stent and containing the stent in its reduced delivery configuration and a pull back means connected to the retractable distal sheath. The system further comprises an arrangement wherein the retractable sheath is pulled into the catheter when the pull back means is pulled proximally and the distal sheath is retracted, freeing the stent for delivery.

Claims

1. A stent delivery system comprising:

a catheter body having a proximal end and a distal end;

a proximal outer body portion of the catheter extending distally and terminating before the distal end of the catheter to leave a stent mounting area;

a stent concentrically carried by the catheter at the mounting area;

a retractable sheath means for exposing the stent comprising a proximal end portion and a distal end portion surrounding at least a portion of the stent, a substantial portion of the proximal end portion of the retractable sheath means distal to the proximal outer body portion of the catheter with a relatively small portion of the proximal end portion of the retractable sheath means received within the outer body portion of the catheter;

a pull back means operatively connected to the retactable sheath for retracting the retractable sheath means, and

wherein the distal end of the proximal outer body portion is constructed and arranged to slidably receive at least the proximal end portion of the retractable sheath means inside the proximal outer body portion upon retraction of the sheath means.

2. The stent delivery system of claim 1 wherein the pull back means comprises a wire.

3. The stent delivery system of claim 1 further comprising an expandable balloon coaxially mounted on the catheter, the stent concentrically carried over at least a portion of the balloon.

4. A stent delivery system comprising:

an elongate flexible catheter comprised of an outer tube of predetermined length having proximal and distal ends and an inner tube of greater length, the inner tube being carried within the outer tube and a portion of the inner tube extending beyond the distal end of the outer tube, the inner tube being relatively non-compressible;

a distal tube having proximal and distal ends and being received over the portion of the inner tube extending beyond the distal end of the outer tube, the proximal end of the distal tube being slidably received into the distal end of the outer tube, the distal end of the distal tube terminating proximally of the distal end of the inner tube to leave a mounting area for a stent on the inner tube;

a manifold and slide mechanism arranged at the proximal ends of the outer and inner tubes;

a stent having a proximal end and a distal end concentrically carried by the inner tube in the mounting area thereof;

a bumper carried by the inner tube and affixed to the inner tube at a position adjacent the proximal end of the stent;

a sheath having proximal and distal ends concentrically arranged about the stent, the proximal end of the sheath being affixed to the distal end of the distal tube;

pull collar carried by the inner tube for movement thereon in a proximal direction, the collar being positioned proximal of the bumper and interiorly affixed to the sheath near its proximal end for retracting the sheath;

pull wire means having a proximal end and a distal end extending from the proximal end portion of the outer tube and therethrough and into and through the distal tube, the distal end of the wire means being connected to the pull collar, the proximal end of the wire means being connected to the slide mechanism whereby, upon movement of the slide mechanism in a proximal direction, the pull wire means moves the pull collar in a proximal direction to retract at least the proximal end of the distal tube into the distal end for the outer tube thereby initiating release of the stent from the catheter.

5. The delivery system of claim 4 wherein the pull collar is in the form of a ring-like collar.

6. The delivery system of claim 4 wherein the outer tube is a two-piece construction comprised of a proximal portion and a distal portion affixed together, the distal portion receiving the distal tube.

7. The delivery system of claim 6 wherein the proximal outer tube portion is of smaller outer diameter than the distal portion and the distal portion fits over the proximal portion for connection therebetween.

8. The delivery system of claim 4 wherein the distal tube is a dual lumen tube and one lumen fits over the inner tube, the other lumen receiving the pull wire means.

9. The stent delivery system of claim 4 further comprising an expandable balloon coaxially mounted on the inner tube, the stent concentrically carried over at least a portion of the balloon.