Stent and system and method for deploying a stent

• US 20070233232A1
• Filed: 03/31/2006
• Published: 10/04/2007
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: St. Jude Medical Cardiology Division Incorporated (Abbott Laboratories)
• Original Assignee: St. Jude Medical Cardiology Division Incorporated (Abbott Laboratories)
• Inventors: Adams, Daniel, St. Germain, Jon
• Granted Patent: US 8,652,192 B2
• Time in Patent Office: Days
• US Class Current: 623/1.150
• CPC Class Codes: A61F 2/852 Two or more distinct overlapping stents
• 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 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91591 Locking connectors, e.g. using male-female connections
• CPC Class Codes: A61F 2002/9665 with additional retaining means
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0063 Nested prosthetic parts
• CPC Class Codes: A61F 2250/0071 breakable or frangible

Abstract

The present invention is a vascular stent comprising a cylindrical wall radially expandable from a compressed state to an expanded state and including a plurality of cells. At least one cell includes a first primary member having a first restrainer member and a second primary member having a second restrainer member. When the cylindrical wall is in the expanded state, the first and second primary members are located a greater distance from each other than when the cylindrical wall is in the compressed state. The first and second restrainer members join to maintain the cylindrical wall in the compressed state. An expansion force applied to the cylindrical wall causes the first and second restrainer members to separate, thereby freeing the cylindrical wall to expand from the compressed state to the expanded state.

Claims

1. A vascular stent comprising:

a cylindrical wall radially expandable from a compressed state to an expanded state and including a plurality of cells, at least one cell including a first primary member having a first restrainer member and a second primary member having a second restrainer member,

wherein, when the cylindrical wall is in the expanded state, the first and second primary members are located a greater distance from each other than when the cylindrical wall is in the compressed state,

wherein the first and second restrainer members join to maintain the cylindrical wall in the compressed state,

wherein an expansion force applied to the cylindrical wall causes the first and second restrainer members to separate, thereby freeing the cylindrical wall to expand from the compressed state to the expanded state.

2. The stent of claim 1, wherein the first primary member includes a first end joining a first end of the second primary member and a second end joining a second end of the second primary member.

3. The stent of claim 2, wherein the first and second primary members deflect near their respective longitudinal centers when the cylindrical wall expands from the compressed state to the expanded state.

4. The stent of claim 3, wherein the first and second restrainer members are located near the longitudinal centers of their respective primary members.

5. The stent of claim 1, wherein each primary member includes first and second ends and wherein said at least one cell further includes a first pair of intermediate members extending between the first ends of the primary members and a second pair of intermediate members extending between the second ends of the primary members.

6. The stent of claim 5, wherein the primary and intermediate members are oriented generally parallel to each other when the cylindrical wall is in the compressed state.

7. The stent of claim 6, wherein the primary members are oriented generally parallel to each other and the intermediate members are generally nonparallel to the primary members when the cylindrical wall is in the expanded state.

8. The stent of claim 7, wherein the intermediate members form an acute angle with the immediately adjacent primary member when the cylindrical wall is in the expanded state.

9. The stent of claim 1, wherein the first primary member includes a first end joining a first end of the second primary member and a second end displaceable from a second end of the second primary member.

10. The stent of claim 9, wherein first restrainer member is located near the second end of the first primary member and the second restrainer member is located near the second end of the second primary member.

11. The stent of any one of the claims 1, 4, 5 or 10, in which the first restrainer member mechanically engages the second restrainer member.

12. The stent of claim 11, wherein the first restrainer member is received in the second restrainer member.

13. The stent as in any one of the claims 1, 4, 5 or 10, in which the first and second restrainer members are bonded together.

14. The stent of claim 13, wherein the bond is formed by sonic welding, heat welding, chemical welding, mechanical welding or by the uninterrupted integral extension of one primary member to the other primary member.

15. The stent of claim 1, wherein the stent is generally self-expanding once the first and second restrainer members separate.

16. The stent of claim 1, wherein the stent generally requires the application of an expanding force to fully expand the stent once the first and second restrainer members separate.

17. A system for deploying a vascular stent, the system comprising:

a catheter including a balloon at a distal end of the catheter; and

a radially expandable stent extending about the balloon and including a plurality of integral restrainer members maintaining the stent in a collapsed state,

wherein expanding the balloon causes the restrainer members to release, thereby allowing the stent to expand.

18. The system of claim 17, wherein each restrainer member includes a first mechanical engagement feature and a second mechanical coupling engagement feature, each feature being an integrally formed part of the stent.

19. The system of claim 18, wherein the first mechanical engagement feature engages the second mechanical engagement feature to maintain the stent in the collapsed state.

20. The system of claim 18, wherein the first mechanical engagement feature is received in the second mechanical engagement feature when the restrainer member is maintaining the stent in the collapsed state.

21. The system of claim 19, wherein first mechanical engagement feature separates from the second mechanical engagement feature when the restrainer member is caused to release via the balloon expansion.

22. The system of claim 17, wherein each restrainer member includes a first portion and a second portion, each portion being an integrally formed part of the stent and the portions being bonded to each other.

23. The system of claim 22, wherein the first and second portions are bonded together via sonic welding, heat welding, chemical welding, mechanical welding or an uninterrupted integral extension of one portion to the other portion forming the restrainer member.

24. The system of claim 22, wherein a bond between the first and second portions fails and the first and second portions separate from each other when the restrainer member is caused to release via the balloon expansion.

25. The system of claim 17, wherein the stent is generally self-expanding once the restrainer members separate.

26. The system of claim 17, wherein the stent generally requires further expansion of the balloon to fully expand the stent once the restrainer members separate.

27. The system of claim 17, wherein the restrainer members on a first portion of the stent are adapted to fail or release prior to the restrainer members on a second portion of the stent.

28. A method of deploying a vascular stent via a balloon catheter in a treatment area of a body lumen, the method comprising:

positioning in the treatment area the stent in a collapsed state on a balloon of the catheter, wherein the stent is maintained in the collapsed state via a plurality of restrainers integral to the stent; and

causing the restrainers to separate by expanding the stent via balloon expansion.

29. The method of claim 28, wherein the treatment area includes a stenosis to be encountered by the stent.

30. The method of claim 28, wherein the stent comprises a plurality of adjacent struts and each restrainer includes a bond between a pair of struts.

31. The method of claim 30, wherein the bond is a sonic weld, a heat weld, a chemical weld, a mechanical weld or an uninterrupted integral extension of one strut to the other strut forming the pair of struts.

32. The method of claim 28, wherein the stent comprises a plurality of adjacent struts and each restrainer includes a first engagement feature on a first strut and a second engagement feature on a second strut, said engagement features interacting to mechanically couple said struts together.

33. The method of claim 28, wherein the stent is generally self-expanding once the restrainers separate.

34. The method of claim 28, wherein the stent generally requires the application of an expanding force to fully expand the stent once the restrainers separate.

35. A method of treating a stenosis in a body lumen wherein pre-expansion of the stenosis is not required prior to stent deployment, the method comprising:

providing a stent mounted on a balloon of a catheter;

retaining the stent in a compressed or non-deployed state about the balloon via a retaining member integral to the stent;

positioning the stent within a stenosis without first pre-expanding the stenosis; and

deploying the stent against the stenosis by expanding the balloon.

36. The method of claim 35, wherein the retaining member uncouples as the balloon is expanded.

37. The method of claim 35, wherein the retaining member fails as the stent is expanded by the balloon.

38. A stent deploying system comprising:

a balloon catheter comprising a tubular body and a balloon coupled to the tubular body near a distal end of the tubular body;

an expandable stent on the balloon; and

means for restraining the stent in a collapsed state.

39. A vascular stent comprising means for restraining the stent in a collapsed state.

40. A stent deploying system comprising:

a balloon catheter including a tubular body and a balloon coupled to the tubular body near a distal end of the tubular body; and

a vascular stent on the balloon, the stent including a restrainer member that is integral to the stent and acts to hold the stent in a collapsed state,

wherein when the balloon is caused to expand, the ability of the restrainer member to hold the stent in the collapsed state is overcome and the stent is free to expand.

41. The system of claim 40, wherein the stent further includes a plurality of adjacent struts and the restrainer member includes a bond between a pair of struts, wherein the bond is adapted to fail upon expansion of the balloon.

42. The system of claim 41, wherein the bond is a sonic weld, a heat weld, a chemical weld, a mechanical weld or an uninterrupted integral extension of one strut to the other strut.

43. The system of claim 40, wherein the stent further includes a plurality of adjacent struts and the restrainer member includes a first coupling member on a first strut and a second coupling member on a second strut, the coupling members interacting to mechanically couple the first and second struts together.

44. The system of claim 43, wherein the coupling members decouple upon expansion of the balloon.

45. A radially expandable stent comprising a plurality of restrainer members that are integral to the stent and adapted to maintain the stent in a compressed state, wherein the restrainer members on a first portion of the stent are adapted to fail or release prior to the restrainer members on a second portion of the stent.

46. The stent of claim 45, wherein the first portion is a middle portion of the stent and the second portion is an end portion of the stent.

47. The stent of claim 45, wherein the first portion is an end portion of the stent and the second portion is middle portion of the stent.