STENT GRAFTS FOR THE THORACIC AORTA

• US 20080294234A1
• Filed: 05/12/2008
• Published: 11/27/2008
• Est. Priority Date: 05/11/2007
• Status: Active Grant

• Current Assignee: Cook Medical Incorporated (Cook Group Incorporated)
• Original Assignee: Cook Incorporated (Cook Group Incorporated), William A. Cook Australia Pty. Ltd (Cook Group Incorporated)
• Inventors: Hartley, David Ernest, Ducke, Werner Dieter
• Granted Patent: US 8,377,113 B2
• Time in Patent Office: Days
• US Class Current: 623/1.12
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/954 for placing stents or stent-grafts in a bifurcation
• CPC Class Codes: A61F 2/962 having an outer sleeve
• CPC Class Codes: A61F 2002/061 provided with means for allowing access to secondary lumens
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/9511 the retaining means being filaments or wires
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2250/001 for adjusting a diameter

Abstract

A method of temporarily reducing the diameter of a stent graft (10) and a stent graft with its diameter reduced. The stent graft has a tubular body and self expanding stents. The method comprising extending a release wire (18, 20) part helically along the graft material tube from substantially one side of the graft material tube at one end (14) of the graft material tube to substantially the opposite side of the graft material tube at the other end (12) of the graft material tube along the stent graft and stitching the release wire into the graft material tube, at each of a number of positions along the release wire looping flexible threads (22, 24) around the release wire and extending the flexible threads laterally around the circumference of the stent graft in each direction to a position away from the release wire, engaging the first flexible threads into the graft material or around struts of the stent, and drawing the ends of the thread together and tying ends of the thread to thereby temporarily reduce the overall diameter of the stent graft.

Claims

1. A temporary diameter reduction constraint arrangement for a stent graft, the stent graft comprising a biocompatible graft material tube of a selected diameter and having a first end and a second end and a plurality of self expanding stents fastened thereto, the constraint arrangement comprising at least one release wire extending part helically along the graft material tube from substantially one side of the graft material tube at the first end of the graft material tube to substantially the opposite side of the graft material tube at the second end of the graft material tube and a plurality of circumferential threads spaced apart at positions along the graft material tube and engaged around the release wire and a portion of the stent graft circumferentially spaced a selected distance away from the release wire and drawn tight and tied to reduce the circumference and hence the overall diameter of the stent graft.

2. A constraint arrangement as in claim 1 wherein the circumferential thread extends circumferentially in each direction from the release wire at each of the positions.

3. A constraint arrangement as in claim 1 wherein the stents are zig-zag stents comprising struts and bends therebetween and the engagement of the flexible thread into the graft material includes the engagement of the thread around a strut of the self expanding stent.

4. A constraint arrangement as in claim 1 wherein the selected distance is reduced by from 50 to 75%.

5. A constraint arrangement as in claim 1 comprising two release wires and a circumferential thread extending circumferentially in each direction from each of the release wires at the plurality of positions along the release wires to hold the stent graft at a reduced diameter of the stent graft along the length of the stent graft.

6. A method of temporarily reducing the diameter of a stent graft at a plurality of positions along the stent graft, the stent graft comprising a tubular body of a biocompatible graft material and having a first end and a second end and a plurality of self expanding stents, the method comprising the steps of;

a) extending a release wire part helically along the graft material tube from substantially one side of the graft material tube at the first end of the graft material tube to substantially the opposite side of the graft material tube at the second end of the graft material tube along the stent graft and stitching the release wire into the graft material tube;

b) at each of a plurality of positions along the release wire looping a first flexible thread around the release wire and extending the first flexible thread laterally around the circumference of the stent graft to a position a selected distance from the release wire;

c) engaging the first flexible thread into the graft material, and

d) drawing the ends of the thread together and tying ends of the thread,

whereby the selected distance is reduced thereby temporarily reducing the overall diameter of the stent graft.

7. A method as in claim 6 wherein the stents are zig-zag stents comprising struts and bends therebetween and the step of engaging the first flexible thread into the graft material includes engaging the thread around a strut of a self expanding stent.

8. A method as in claim 6 further comprising the steps of;

e) passing a second flexible thread around the release wire and extending the second flexible thread laterally around the circumference of the stent graft in the opposite direction to the first flexible thread to a position a selected distance from the release wire at each of the plurality positions along the length of the release wire;

f) engaging the second flexible thread into the graft material, and

g) drawing the ends of the second thread together and tying ends of the thread,

whereby the selected distance is reduced thereby reducing the overall diameter of the stent graft.

9. A method in claim 6 wherein the selected distance is reduced by from 50 to 75%.

10. A method as in claim 6 further comprising the steps of;

j) extending a second release wire along the stent graft on an opposite side of the graft material tube from substantially one side of the graft material tube at the first end of the graft material tube to substantially the opposite side of the graft material tube at the second end of the graft material tube along the stent graft and stitching the release wire into the graft material tube;

k) looping a third flexible thread around the second release wire and extending the third flexible thread laterally around the circumference of the stent graft to a position a selected distance from the second release wire;

l) engaging the third flexible thread into the graft material, and

m) drawing the ends of the thread together and tying ends of the thread,

n) passing a fourth flexible thread around the release wire or around the third and extending the fourth flexible thread laterally around the circumference of the stent graft in the opposite direction to the third flexible thread to a position a selected distance from the second release wire;

o) engaging the fourth flexible thread into the graft material, and

p) drawing the ends of the fourth thread together and tying ends of the thread,

whereby the selected distance is reduced thereby reducing the overall diameter of the stent graft.

11. A temporary diameter reduction and constraint arrangement for a stent graft, the stent graft comprising a biocompatible graft material tube of a selected diameter and a plurality of self expanding stents fastened thereto, the stents comprising zig-zag stents comprising struts and bends therebetween, the temporary diameter reduction and constraint arrangement comprising two release wires extending longitudinally and helically in opposite directions along the graft material tube from substantially one side of the graft material tube at the first end of the graft material tube to substantially the opposite side of the graft material tube at the second end of the graft material tube, the release wires being stitched into the graft material tube, at a plurality of positions along each release wire two threads engaged around each release wire and a selected strut of a stent and portion of the stent graft circumferentially spaced a selected distance away from each release wire in each circumferential direction from the respective release wires and drawn tight to compress the self expanding stent between the selected strut and the release wire and tied to reduce the circumference and hence the overall diameter of the stent graft.