Methods for improving stent retention on a balloon catheter

• US 8,333,000 B2
• Filed: 06/19/2006
• Issued: 12/18/2012
• Est. Priority Date: 06/19/2006
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Huang, Bin, Gale, David C., Castro, Daniel
• Primary Examiner(s): Jackson, Gary
• Assistant Examiner(s): STRANSKY, KATRINA MARIE
• Application Number:
  US11/471,375
• Publication Number:
  US 20070289117A1
• Time in Patent Office: 2,374 Days
• Field of Search: 623/1.11, 294/070.8
• US Class Current: 29/282
• 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 2002/9505 having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument
• 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 2002/9586 the means being inside the balloon
• CPC Class Codes: B23P 11/005 by expanding or crimping
• CPC Class Codes: Y10T 29/49863 with prestressing of part
• CPC Class Codes: Y10T 29/49913 by constricting outer annulus
• CPC Class Codes: Y10T 29/49925 Inward deformation of aperture or hollow body wall
• CPC Class Codes: Y10T 29/49927 Hollow body is axially joined cup or tube
• CPC Class Codes: Y10T 29/53065 with means to fasten by deformation
• CPC Class Codes: Y10T 29/53987 Tube, sleeve or ferrule

Abstract

A method of crimping a stent on a balloon of a catheter assembly is provided. A polymeric stent is disposed over a balloon in an inflated configuration. The stent is crimped over the inflated balloon to a reduced crimped configuration so that the stent is secured onto the balloon. The balloon wall membrane is wedged or pinched between the strut elements of the stent for increasing the retention of the stent on the balloon.

Claims

1. A method of crimping a stent on a balloon, comprising the following acts in the order as listed:

(a) providing a poly (L-lactide) stent disposed over a balloon in an inflated configuration, the balloon being inflated by a fluid at a temperature of a glass transition temperature (T_g) of the poly (L-lactide) stent;

(b) crimping the stent to a first reduced diameter;

(c) at least partially deflating the balloon;

(d) inflating the balloon to at least an inner diameter of the stent; and

(e) crimping the stent to a second reduced diameter.

2. The method of claim 1, wherein the second reduced diameter is a final crimped diameter.

3. The method of claim 2, additionally comprising, following act (e):

(f) at least partially deflating the balloon;

followed by

(g) inflating the balloon to at least an inner diameter of the stent;

followed by

(e) crimping the stent to a third reduced diameter.

4. The method of claim 3, wherein the third reduced diameter is a final crimped diameter.

5. A stent-balloon catheter assembly made in accordance with the method of claim 1.

6. The method of claim 1, wherein a balloon softening fluid is applied to the balloon.

7. The method of claim 1, wherein a solvent is applied to the balloon surface.

8. The method of claim 1, wherein the crimping is performed using a crimper.

9. The method of claim 8, wherein the crimper is an iris crimper.

10. The method of claim 8, wherein the crimper includes jaws configured to move inward.

11. The method of claim 1, wherein the crimping of steps (b) and (d) include radially compressing the stent between jaws of a crimper.

12. The method of claim 1, wherein the stent is in a crimping device for steps (b) and (d).

13. The method of claim 12, wherein the balloon is inflated before being placed in the crimping device.

14. The method of claim 1, wherein prior to step (c) the balloon has a crimp inflation state that is greater than a collapsed state of the balloon.

15. The method of claim 1, wherein subsequent to crimping the stent to the second reduced diameter a membrane or wall of the balloon is pinched or wedged between structural elements of the stent.

16. The method of claim 1, wherein during at least step (b) the pressure in the balloon is controllably released by a valve.