Distally attachable and releasable sheath for a stent delivery system

• US 5,735,859 A
• Filed: 02/14/1997
• Issued: 04/07/1998
• Est. Priority Date: 02/14/1997
• Status: Expired due to Fees

• Current Assignee: Cathco, Inc.
• Original Assignee: Cathco, Inc.
• Inventors: Fischell, David R., Fischell, Robert E., Fischell, Tim A.
• Primary Examiner(s): Buiz, Michael
• Assistant Examiner(s): PHAM, THUY D
• Application Number:
  US08/800,613
• Time in Patent Office: 417 Days
• Field of Search: 606/191, 606/198, 606/108
• US Class Current: 606/108
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing 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 is a device and method for securing and releasing the distal end of a thin-walled sheath to and from a distal section of a stent delivery catheter. The invention comprises a stent delivery catheter system which includes a sheath which is releasably attached to a distal section of a stent delivery catheter. When the stent delivery system has been advanced into the body so that the stent (which is situated coaxially within the sheath) is placed at the site of an arterial stenosis where it is to be deployed, the sheath is released from the stent delivery catheter and then the sheath is pulled back in a proximal direction thereby uncovering the stent. Self-deploying stents will automatically deploy when the sheath is pulled back. Balloon expandable stents can be deployed by balloon inflation after the sheath has been pulled back. One embodiment of the distally attachable and releasable sheath utilizes a guide wire that passes through the stent delivery catheter first to hold and then to release the distal end of the sheath from a distal section of the stent delivery catheter.

Claims

1. A stent delivery catheter system for placing a stent within a vessel of a human body, the system comprising:

a flexible guide wire;

a stent delivery catheter having a distal section which includes a radially expandable metal stent, the stent delivery catheter also having a central lumen through which the guide wire can be slideably placed;

a sheath having a distal end and having at least one tab located at its distal end, the sheath being coaxially and slideably placed around the stent delivery catheter; and

the at least one tab of the sheath being releasably attached by the guide wire to a fitting located at the distal section of the stent delivery catheter.

2. The invention of claim 1 wherein there are two tabs.

3. The invention of claim 1 wherein there is at least one hole in the tab through which the guide wire can be passed.

4. The invention of claim 1 wherein the fitting at the distal section of the stent delivery catheter has at least one slot into which the tab can be inserted.

5. The invention of claim 4 wherein there are two slots.

6. The invention of claim 1 wherein the stent delivery catheter uses an inflatable balloon to deploy the stent.

7. The invention of claim 1 wherein the stent is self-expanding.

8. A stent delivery catheter system for placing a stent within a vessel of a human body, the system comprising:

a flexible guide wire;

a stent delivery catheter system having a distal section which includes a radially expandable metal stent, the stent delivery catheter also having a central lumen through which the guide wire can be slideably placed;

a slidable sheath covering the stent, the sheath having a distal end which is releasably attached by the guide wire to the distal section of the stent delivery catheter.

9. A method for placing a stent within a stenosed blood vessel of the human body, the method comprising the following steps:

(a) placing a flexible guide wire having a distal end through the vascular system of the human body until the guide wire'"'"'s distal end lies distal to the vessel stenosis;

(b) advancing a stent delivery catheter system over the guide wire which stent delivery catheter system includes a stent delivery catheter having a distal section, a stent located at said distal section of the stent delivery catheter and a sheath that is coaxially and slideably mounted around the stent delivery catheter, the sheath having at least one tab at its distal end which tab has a central hole through which the guide wire can pass, the at least one tab being placed into a fitting at the distal end of the stent delivery catheter;

(c) continuing to advance the stent delivery catheter system until the stent located at the distal end of the stent delivery catheter is situated at the site of the vessel stenosis;

(d) pulling back the guide wire until its distal end lies proximal to the at least one tab of the sheath;

(e) pulling back the sheath relative to the stent delivery catheter until the stent is uncovered; and

(f) deploying the stent at the site of the vessel stenosis.

10. The method of claim 9 wherein the stent is a balloon expandable stent and the stent delivery catheter is a balloon angioplasty catheter having an inflatable balloon at the distal section of the stent delivery catheter and the stent is deployed to open the vessel obstruction by inflating the balloon.

11. The method of claim 10 further including the step of deflating the balloon and removing the stent delivery catheter and sheath from the human body.

12. The method of claim 9 wherein the stent is a self-expanding stent which automatically deploys radially outward against the wall of the vessel after the sheath is pulled back.

13. A method for placing a stent within a stenosed blood vessel of the human body, the method comprising the following steps:

(a) placing a flexible guide wire having a distal end through the vascular system of the human body until the guide wire'"'"'s distal end lies distal to the vessel stenosis;

(b) advancing a stent delivery catheter system over the guide wire which stent delivery catheter system includes a stent delivery catheter having a distal section, a radially expandable metal stent located at said distal section of the stent delivery catheter and a sheath that is coaxially and slideably mounted around the stent delivery catheter, the distal end of the sheath being releasably attached by the guide wire to the distal section of the stem delivery catheter;

(c) continuing to advance the stent delivery catheter system until the stent located at the distal end of the stent delivery catheter is situated at the site of the vessel stenosis;

(d) detaching the distal end of the sheath from the distal section of the stent delivery catheter;

(e) pulling back the sheath relative to the stent delivery catheter until the stent is uncovered; and

(f) deploying the stent at the site of the vessel stenosis.