Temperature activated adhesive for releasably attaching stents to balloons

• US 6,066,156 A
• Filed: 03/11/1999
• Issued: 05/23/2000
• Est. Priority Date: 03/11/1999
• Status: Expired due to Fees

• Current Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Yan, John Y.
• Primary Examiner(s): Hirsch, Paul J.
• Assistant Examiner(s): Priddy, Michael B
• Application Number:
  US09/266,426
• Time in Patent Office: 439 Days
• Field of Search: 606/108, 606/191, 606/192, 606/194, 606/96, 606/103
• US Class Current: 606/192
• 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 2002/30448 using adhesives
• 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 2220/005 using adhesives

Abstract

A delivery catheter, with or without an inflation balloon, and coated with a heat activated adhesive to secure a stent thereon is disclosed. The adhesive has a phase transformation temperature just above the temperature of human blood, so that below the transformation temperature the adhesive is tacky, and above the transformation temperature the adhesive is non-tacky. In a stenting procedure, when the stent is mounted to the balloon catheter and the catheter is introduced into a body lumen, the adhesive is below the transformation temperature and remains tacky to hold the stent to the catheter. Once the stent-catheter assembly is positioned at the deployment site, a warm saline or dye solution is injected to heat the adhesive to above the transformation temperature. The adhesive becomes non-tacky and releases the bond between the catheter and deployed stent allowing the former to be withdrawn.

Claims

1. A stent delivery catheter for delivering a stent, comprising:

a catheter body having a shaft portion;

a layer of heat sensitive adhesive disposed on the shaft portion, wherein the adhesive is tacky at and below a temperature T, and is non-tacky above T;

wherein the stent is disposed on the layer of heat sensitive adhesive.

2. The stent delivery catheter of claim 1, wherein the shaft portion includes a balloon and the adhesive is disposed on the balloon.

3. The stent delivery catheter of claim 1, wherein temperature T is greater than 38°

C. and less than 47°

C.

4. The stent delivery catheter of claim 1, wherein temperature T includes a phase transformation temperature.

5. The stent delivery catheter of claim 1, wherein the layer of heat sensitive adhesive ranges between 0.000010 inch and 0.005 inch.

6. The stent delivery catheter of claim 1, wherein the heat sensitive adhesive includes a phase change from 38°

to 47°

C. inclusive.

7. The stent delivery catheter of claim 1, wherein the adhesive includes a crystallizable polymer.

8. The stent delivery catheter of claim 1, wherein the adhesive includes polyacrylate.

9. The stent delivery catheter of claim 1, wherein the adhesive includes styrene/butadiene.

10. The stent delivery catheter of claim 1, wherein the adhesive includes a degree of tack ranges from less than 25 g-cm/sec to greater than 100 g-cm/sec.

11. A stent delivery catheter for delivering a stent, comprising:

a catheter body having a shaft portion;

a layer of heat sensitive adhesive disposed on the shaft portion, wherein the adhesive is in a first phase at and below a temperature T, and is in a second phase above temperature T;

wherein the stent is disposed on the layer of heat sensitive adhesive.

12. The stent delivery catheter of claim 11, wherein the shaft portion includes a balloon and the adhesive is disposed on the balloon.

13. The stent delivery catheter of claim 11, wherein the adhesive is in a tacky state in the first phase, and the adhesive is in a less than tacky state in the second phase.

14. The stent delivery catheter of claim 11, wherein the adhesive is melted in the second phase.

15. A method for delivering a stent by a catheter comprising the steps of:

providing the delivery catheter with a shaft portion;

applying a heat sensitive adhesive to the shaft portion, the adhesive having a tacky state below and at a temperature T, and a less than tacky state above temperature T;

mounting the stent on the shaft portion so that the stent contacts the adhesive; and

heating the adhesive to above temperature T.

16. The method of claim 15, wherein the method further comprises the steps of:

applying the adhesive to the shaft at below temperature T;

placing the catheter and stent into a vessel of a patient;

heating the adhesive to above temperature T; and

withdrawing the catheter from the stent.

17. The method of claim 16, wherein the step of heating the adhesive includes injecting warm saline into the vessel.

18. The method of claim 16, wherein the step of heating the adhesive includes injecting warm dye solution into the vessel.

19. The method of claim 15, wherein the method further comprises the steps of:

providing a deflated balloon at the shaft portion;

applying the heat sensitive adhesive to the balloon at below temperature T;

mounting the stent on the balloon;

placing the catheter and stent into a vessel of a patient;

inflating and deflating the balloon to deploy the stent;

heating the adhesive to above temperature T; and

withdrawing the catheter from the stent.

20. The method of claim 15, wherein temperature T is the phase transformation temperature of the adhesive.

21. A stent delivery catheter for delivering a stent having a plurality of struts with an interstitial space therebetween, comprising:

a catheter body having a shaft portion, wherein the stent is crimped on the shaft portion; and

a layer of heat sensitive adhesive disposed on the shaft portion at least partially within the intertitial space of the stent, wherein the adhesive is tacky at and below a temperature T, and is non-tacky above T.

22. The stent delivery catheter of claim 21, wherein the shaft portion includes a balloon and the stent is crimped on the balloon.

23. The stent delivery catheter of claim 21, wherein temperature T is greater than 38°

C. and less than 47°

C.

24. The stent delivery catheter of claim 21, wherein temperature T includes a phase transformation temperature of the adhesive.

25. A method for delivering a stent having struts separated by an interstitial space on a catheter comprising the steps of:

providing the delivery catheter with a shaft portion;

crimping the stent on to the shaft portion; and

applying a heat sensitive adhesive to the shaft portion to at least partially fill in the interstitial space of the stent, wherein the adhesive has a tacky state below and at a temperature T, and a less than tacky state above temperature T.

26. The method of claim 25, wherein the method further comprises the step of heating the adhesive to above temperature T.

27. The method of claim 25, wherein the method further comprises the steps of:

applying the adhesive to the shaft at below temperature T;

placing the catheter and stent into a vessel of a patient;

heating the adhesive to above temperature T; and

withdrawing the catheter from the stent.

28. The method of claim 25, wherein the catheter shaft portion includes a balloon portion and the stent is crimped to the balloon portion.