Cold-molding process for loading a stent onto a stent delivery system

• US 20030055482A1
• Filed: 09/19/2001
• Published: 03/20/2003
• Est. Priority Date: 09/19/2001
• Status: Active Grant

• Current Assignee: Abbott International Enterprises Ltd. (Abbott Laboratories Incorporated)
• Original Assignee: Jomed GmbH
• Inventors: Schwager, Michael, Frei, Martin, Ha, Suk-Woo
• Granted Patent: US 6,863,683 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/9583 Means for holding the stent on the balloon, e.g. using protrusions, adhesives or an outer sleeve
• CPC Class Codes: A61F 2310/00011 Metals or alloys
• CPC Class Codes: A61M 2025/1004 Balloons with folds, e.g. folded or multifolded
• CPC Class Codes: Y10T 29/49927 Hollow body is axially joined cup or tube

Abstract

A method of making a stent delivery system is provided in which a delivery catheter has a balloon that extends non-uniformly into interstices of a stent. In accordance with the method a balloon/stent/crimping tube assembly is placed in a crimping tool, the balloon is inflated, and the crimping tool is actuated to compress the stent on the outside of the balloon without application of heat or chemicals, thereby causing creases of the balloon to extend non-uniformly into the interstices of the stent. Optionally, pillows may be formed in the balloon to prevent longitudinal movement of the stent with respect to the balloon during intravascular delivery. One or more secondary crimpings also may be performed to achieve a smoother delivery profile.

Claims

1. A stent delivery system having a contracted delivery configuration and an expanded deployed configuration, the stent delivery system comprising:

a stent; and

a delivery catheter having an inflatable balloon, the stent disposed about the balloon, wherein the balloon comprises creases that extend non-uniformly within interstices of the stent in the contracted delivery configuration.

2. The stent delivery system of claim 1, wherein the inflatable balloon further comprises pillows disposed proximally and distally of the stent in the contracted delivery configuration.

3. The stent delivery system of claim 1, wherein the delivery catheter further comprises markers.

4. The stent delivery system of claim 3, wherein the markers are radiopaque.

5. The stent delivery system of claim 1, wherein the stent comprises an external coating.

6. The stent delivery system of claim 5, wherein the coating is configured to retard restenosis or thrombus formation around the stent.

7. The stent delivery system of claim 5, wherein the coating is configured to deliver therapeutic agents into a patient'"'"'s blood stream or vessel wall when implanted within the patient'"'"'s vasculature.

8. A method of fabricating a stent delivery system comprising:

providing apparatus comprising a stent and a delivery catheter having an inflatable balloon;

disposing the stent about the inflatable balloon;

placing the balloon and stent within a crimping tool;

inflating the balloon;

actuating the crimping tool to compress the stent on the outside of the balloon at a substantially constant temperature, thereby causing the balloon to extend non-uniformly into interstices of the stent; and

deflating the balloon while the crimping tool is still actuated, thereby securing non-uniform creases of the balloon within the interstices of the stent and forming the stent delivery system.

9. The method of claim 8 further comprising removing the stent delivery system from the crimping tool.

10. The method of claim 8, wherein deflating the balloon further comprises forming proximal and/or distal pillows.

11. The method of claim 8 further comprising performing secondary crimping.

12. The method of claim 11, wherein secondary crimping comprises:

de-actuating the crimping tool; and

re-actuating the crimping tool to further compress the stent on the outside of the balloon.

13. The method of claim 12 further comprising de-actuating the crimping tool.

14. The method of claim 8, wherein inflating the balloon further comprises partially inflating the balloon.

15. A method of fabricating a stent delivery system comprising:

providing apparatus comprising a stent and a delivery catheter having an inflatable balloon;

disposing the stent about the inflatable balloon;

placing an elastic crimping tube over the stent and balloon;

placing the balloon, stent, and elastic crimping tube within a crimping tool;

inflating the balloon;

actuating the crimping tool to compress the stent on the outside of the balloon at a substantially constant temperature, thereby causing the balloon to extend non-uniformly into interstices of the stent; and

deflating the balloon while the crimping tool is still activated, thereby securing non-uniform creases of the balloon within the interstices of the stent and forming the stent delivery system.

16. The method of claim 15 further comprising de-actuating the crimping tool and removing the stent delivery system from the elastic crimping tube.

17. The method of claim 15, wherein deflating the balloon further comprises forming proximal and/or distal pillows.

18. The method of claim 16 further comprising performing secondary crimping.

19. The method of claim 18, wherein secondary crimping comprises:

placing a semi-rigid crimping tube over the stent delivery system;

placing the stent delivery system and semi-rigid crimping tube within the crimping tool; and

re-actuating the crimping tool to further compress the stent on the outside of the balloon.

20. The method of claim 19 further comprising de-actuating the crimping tool and removing the stent delivery system from the semi-rigid crimping tube.

21. The method of claim 19, wherein re-actuating the crimping tool comprises actuating the crimping tool in sections along a length of the stent delivery system.

22. The method of claim 15, wherein inflating the balloon further comprises partially inflating the balloon.

23. A method of fabricating a stent delivery system comprising:

providing apparatus comprising a stent and a delivery catheter having an inflatable balloon;

disposing the stent about the inflatable balloon;

placing the balloon and stent within a crimping tool;

inflating the balloon;

deflating the balloon; and

actuating the crimping tool to compress the stent on the outside of the balloon at a substantially constant temperature, thereby securing non-uniform creases of the balloon within the interstices of the stent and forming the stent delivery system.

24. A method for stenting at a target site within a patient'"'"'s vessel, the method comprising:

providing a stent delivery system comprising a stent and a delivery catheter with an inflatable balloon, the stent disposed about the inflatable balloon, wherein the balloon has creases that extend non-uniformly within interstices of the stent;

percutaneously delivering the stent delivery system to the target site within the patient'"'"'s vessel in a contracted delivery configuration; and

expanding the stent delivery system to an expanded deployed configuration, wherein the balloon is inflated, the interstices of the stent open, removing the creases of the balloon from the interstices, and the stent engages the target site.

25. The method of claim 24 further comprising:

deflating the balloon; and

removing the delivery catheter from the patient'"'"'s vessel.