Stent crimping methods

Patent metadata

Field	Value
Publication number	US-9308106-B2
Application number	US-201314073793-A
Country	US
Kind code	B2
Filing date	Nov 6, 2013
Priority date	Sep 30, 2010
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A process for crimping stents includes a multi-stage process producing a desired stent retention and crimped profile in a reduced amount of time. The process achieves results by utilizing particular combinations of heat and pressure during the crimping process, which was found to produce the desired results.

First claim

What is claimed is:

1. A method for crimping a stent, comprising:
(a) loading the stent on a mandrel;
(b) placing the stent in a crimper;
(c) reducing the stent profile to a first diameter;
(d) loading the stent onto a balloon of a catheter delivery system after step (c);
(e) placing the stent and the balloon back into the crimper;
(f) pressurizing the balloon and heating a distal end of the catheter delivery system within the crimper to cause pillowing of the balloon between struts of the stent; and
(g) after step (f), moving the crimper between a second and third diameter to reduce the stent diameter to a final diameter, to reduce stent recoil and/or increase a mechanical interaction between the balloon and the stent;
wherein after step (g), further including performing a leak test, wherein
the stent has the final diameter during the leak test, and
the final diameter is less than the second diameter and greater than the third diameter.

2. The method of claim 1 , wherein step (g) further includes opening and closing the crimper between the second and third diameter while the balloon is pressurized, wherein the final diameter is less than the second diameter and the third diameter is between 20-40% less than the final diameter.

3. The method of claim 1 , wherein during step (f) the stent diameter is about 25-30% greater than the first diameter.

4. The method of claim 1 , wherein after step (f) and before step (g) the stent has the second diameter and step (g) includes reducing the stent diameter by up to 40% from the second diameter while a balloon pressure is maintained.

5. The method of claim 1 , wherein during steps (f) and (g) a balloon pressure is constant or varying.

6. A method for crimping a stent, comprising:
(a) loading the stent on a mandrel;
(b) placing the stent in a crimper;
(c) reducing the stent profile to a first outer diameter;
(d) loading the stent onto a balloon of a catheter delivery system after step (c);
(e) placing the stent and the balloon back into the crimper;
(f) pressurizing the balloon and heating a distal end of the catheter delivery system within the crimper to cause pillowing of the balloon between struts of the stent; and
(g) after step (f), moving the crimper between a second and third outer diameter to reduce the stent diameter to a final outer diameter, to reduce stent recoil and/or increase a mechanical interaction between the balloon and the stent;
wherein prior to step (f), further including placing the stent within a sheath having an inner diameter that is about 25% greater than the first diameter.

7. A method for crimping a stent, comprising:
(a) loading the stent on a mandrel;
(b) placing the stent in a crimper;
(c) reducing the stent profile to a first outer diameter;
(d) loading the stent onto a balloon of a catheter delivery system after step (c);
(e) placing the stent and the balloon back into the crimper;
(f) placing the stent within a sheath having an inner diameter between 15% to 30% greater than the first diameter;
(g) after step (f), pressurizing the balloon and heating a distal end of the catheter delivery system within the crimper to cause pillowing of the balloon between struts of the stent; and
(h) after step (g), moving the crimper between a second and third diameter to reduce the stent diameter to a final outer diameter, to reduce stent recoil and/or increase a mechanical interaction between the balloon and the stent.

8. The method of claim 7 , wherein step (h) further includes opening and closing the crimper between the second and third diameter while the balloon is pressurized, wherein the final diameter is less than the second diameter and the third diameter is between 20-40% less than the final diameter.

9. The method of claim 7 , wherein during step (h) the stent outer diameter is 25-30% greater than the first diameter.

10. The method of claim 7 , wherein the second diameter is the final diameter and the third diameter is less than the final diameter.

11. The method of claim 7 , wherein after step (g) and before step (h) the stent has the second diameter and step (h) includes reducing the stent diameter by up to 40% from the second diameter while a balloon pressure is maintained.

12. The method of claim 7 , wherein after step (h), further including performing a leak test, wherein
the stent has the final diameter during the leak test, and
the final diameter is less than the second diameter and greater than the third diameter.

13. The method of claim 7 , wherein during steps (g) and (h) a balloon pressure is constant or varying.

Assignees

• Abbott Cardiovascular Systems

Inventors

• Knott Boyd V
• Kadakia Samit
• Ortega Leopoldo

Classifications

• Y10T29/53952

  Tube sleeve or ferrule applying or removing · CPC title

• Y10T29/49927

  Hollow body is axially joined cup or tube · CPC title

• A61F2/958

  Inflatable balloons for placing stents or stent-grafts · CPC title

• A61F2/9522

  Means for mounting a stent or stent-graft onto or into a placement instrument · CPC title

• A61F2/95 Primary

  Instruments specially adapted for placement or removal of stents or stent-grafts · CPC title