EXPANDABLE STENT AND METHOD FOR DELIVERY OF SAME

• US 20090192590A1
• Filed: 04/07/2009
• Published: 07/30/2009
• Est. Priority Date: 03/05/1996
• Status: Abandoned Application

• Current Assignee: Evysio Medical Devices ULC (Evysio Medical Devices)
• Original Assignee: Evysio Medical Devices ULC (Evysio Medical Devices)
• Inventors: Ricci, Donlad R., PENN, IAN M.
• Application Number:
  US12/419,453
• Publication Number:
  US 20090192590A1
• Time in Patent Office: Days
• US Class Current: 623/1.16
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• 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 2002/825 having longitudinal struts
• CPC Class Codes: A61F 2002/828 Means for connecting a plurality of stents allowing flexibility of the whole structure
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0036 differing in thickness

Abstract

An expandable stent comprising a proximal end and a distal end in communication with one another and a tubular wall disposed between the proximal end and the distal end. The tubular wall has a longitudinal axis and a porous surface defined by a plurality of intersecting members comprising a series of longitudinal struts disposed substantially parallel to the longitudinal axis of the stent. Each longitudinal strut in the series comprises flexure means for substantially complementary extension and compression of a diametrically opposed pair of the longitudinal struts upon flexure of the stent. The stent is expandable from a first, contracted position to a second, expanded position upon the application of a radially outward force on the stent. The provision of such flexure means in the series of longitudinal struts leads to a very desirable balance of lateral flexibility of the unexpanded stent and radial rigidity of the expanded stent.

Claims

1. A stent comprising:

a series of undulating circumferential struts;

a plurality of longitudinal struts connecting said series of undulating circumferential struts to form a porous, cylindrical surface; and

flexure elements within said plurality of longitudinal struts, said plurality of longitudinal struts being arranged around said cylindrical surface such that the flexure elements in adjacent longitudinal portions are located at different distances from said circumferential struts.

2. The stent of claim 1, wherein one or more of said plurality of longitudinal portions includes multiple flexure elements within the same longitudinal portion.

3. The stent of claim 2, wherein all said multiple flexure elements within the same longitudinal portion have a same shape.

4. The stent of claim 2, wherein all said multiple flexure elements within the same longitudinal portion have a different shape.

5. The stent of claim 2, wherein all said multiple flexure elements within the same longitudinal portion have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral section are present on the same side of the longitudinal portion.

6. The stent of claim 2, wherein all said multiple flexure elements within the same longitudinal portion have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral section are present on different sides of the longitudinal portion.

7. The stent defined in claim 1, wherein a relative flexibility of the stent is variable in accordance with a thickness of at least one of the plurality of radially-expandable circumferential struts varying in the range of from about 0.0015 to about 0.0045 inches.

8. The stent defined in claim 1, further comprising a medicinal coating disposed thereon.

9. A stent system comprising a balloon catheter having an expandable portion, the expandable portion having disposed thereon the stent defined in claim 8.

10. The stent defined in claim 1, wherein said multiple flexure elements within the same longitudinal strut have substantially the same shape and differing size.

11. The stent defined in claim 1, wherein said multiple flexure elements within the same longitudinal strut have differing shape and size.

12. The stent defined in claim 1, wherein the porous, cylindrical surface comprises a repeating pattern comprised of a polygon having a pair of side walls substantially parallel to a stent longitudinal axis, and wherein the flexure elements are disposed in each of the side walls.

13. The stent defined in claim 1, wherein the longitudinal struts are aligned in a spaced relationship parallel to a stent longitudinal axis.

14. The stent defined in claim 1, wherein the longitudinal struts are aligned in an interconnected relationship parallel to a stent longitudinal axis.

15. The stent defined in claim 1, wherein the stent is constructed of stainless steel.

16. The stent defined in claim 1, wherein the stent is constructed of a self-expanding material.

17. The stent defined in claim 16, wherein the self-expanding material comprises nitinol.

18. The stent defined in claim 16, wherein the self-expanding material expands at a temperature of greater than about 30°

C.

19. The stent defined in claim 1, wherein said flexure elements, in two dimensions, have a width less than a width of said undulating circumferential struts.

20. The stent defined in claim 1, wherein adjacent undulating circumferential struts have substantially the same profile.

21. The stent defined in claim 1, wherein adjacent undulating circumferential struts have substantially different profiles.

22. A stent comprising:

a series of undulating circumferential members;

a plurality of longitudinal members connecting said series of undulating circumferential members to form a porous, cylindrical surface; and

flexure members within said plurality of longitudinal members, the flexure members of adjacent longitudinal members having different shapes in an unbent form of the stent.

23. The stent of claim 22, wherein one or more of said plurality of longitudinal members includes multiple flexure members within the same longitudinal member.

24. The stent of claim 23, wherein said multiple flexure members within the same longitudinal member have a same shape.

25. The stent of claim 23, wherein said multiple flexure members within the same longitudinal member have a different shape.

26. The stent of claim 23, wherein said multiple flexure members within the same longitudinal member have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral section are present on the same side of the longitudinal member.

27. The stent of claim 23, wherein said multiple flexure members within the same longitudinal member have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral section are present on different sides of the longitudinal member.

28. The stent defined in claim 22, wherein a relative flexibility of the stent is variable in accordance with a thickness of at least one of the plurality of radially-expandable circumferential members varying in the range of from about 0.0015 to about 0.0045 inches.

29. The stent defined in claim 22, further comprising a medicinal coating disposed thereon.

30. A stent system comprising a balloon catheter having an expandable portion, the expandable portion having disposed thereon the stent defined in claim 22.

31. The stent defined in claim 23, wherein said multiple flexure members within the same longitudinal member have substantially the same shape and differing size.

32. The stent defined in claim 23, wherein said multiple flexure members within the same longitudinal member have differing shape and size.

33. The stent defined in claim 22, wherein the porous, cylindrical surface comprises a repeating pattern comprised of a polygon having a pair of side walls substantially parallel to a stent longitudinal axis, and wherein the flexure members are disposed in each of the side walls.

34. The stent defined in claim 22, wherein the longitudinal members are aligned in a spaced relationship parallel to a stent longitudinal axis.

35. The stent defined in claim 22, wherein the longitudinal members are aligned in an interconnected relationship parallel to a stent longitudinal axis.

36. The stent defined in claim 22, wherein the stent is constructed of stainless steel.

37. The stent defined in claim 22, wherein the stent is constructed of a self-expanding material.

38. The stent defined in claim 37, wherein the self-expanding material comprises nitinol.

39. The stent defined in claim 37, wherein the self-expanding material expands at a temperature of greater than about 30°

C.

40. The stent defined in claim 22, wherein said flexure members, in two dimensions, having a width less than a width of said undulating circumferential members.

41. The stent defined in claim 22, wherein adjacent undulating circumferential members have substantially the same profile.

42. The stent defined in claim 22, wherein adjacent undulating circumferential members have substantially different profiles.

43. An expandable stent comprising:

a series of undulating circumferential portions;

a plurality of longitudinal portions connecting said series of undulating circumferential portions to form a porous, cylindrical surface; and

flexure structure that confers lateral flexibility to said unexpanded stent, said flexure structure being located within said plurality of longitudinal portions, said plurality of longitudinal portions being arranged around said cylindrical surface such that the flexure structures in adjacent longitudinal portions are located at different distances from said circumferential portions, and wherein the flexure structures of adjacent longitudinal portions have different shapes.

44. The stent of claim 43, wherein one or more of said plurality of longitudinal portions includes multiple flexure structures within the same longitudinal portion.

45. The stent of claim 44, wherein said multiple flexure structures within the same longitudinal portion have a same shape.

46. The stent of claim 44, wherein said multiple flexure structures within the same longitudinal portion have a different shape.

47. The stent of claim 44, wherein said multiple flexure structures within the same longitudinal portion have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral are present on the same side of the longitudinal portion.

48. The stent of claim 44, wherein said multiple flexure structures within the same longitudinal portion have a first lateral section and a second lateral section, and wherein the first lateral section and the second lateral section are present on different sides of the longitudinal portion.

49. The stent defined in claim 43, wherein a relative flexibility of the stent is variable in accordance with a thickness of at least one of the plurality of radially-expandable circumferential struts varying in the range of from about 0.0015 to about 0.0045 inches.

50. The stent defined in claim 43, further comprising a medicinal coating disposed thereon.

51. A stent system comprising a balloon catheter having an expandable portion, the expandable portion having disposed thereon the stent defined in claim 43.

52. The stent defined in claim 44, wherein said multiple flexure structures within the same longitudinal portion have substantially the same shape and differing size.

53. The stent defined in claim 44, wherein said multiple flexure structures within the same longitudinal portion have differing shape and size.

54. The stent defined in claim 43, wherein the porous, cylindrical surface comprises a repeating pattern comprised of a polygon having a pair of side walls substantially parallel to a stent longitudinal axis, and wherein the flexure structures are disposed in each of the side walls.

55. The stent defined in claim 43, wherein the longitudinal portions are aligned in a spaced relationship parallel to a stent longitudinal axis.

56. The stent defined in claim 43, wherein the longitudinal portions are aligned in an interconnected relationship parallel to a stent longitudinal axis.

57. The stent defined in claim 43, wherein the stent is constructed of stainless steel.

58. The stent defined in claim 43, wherein the stent is constructed of a self-expanding material.

59. The stent defined in claim 43, wherein the self-expanding material comprises nitinol.

60. The stent defined in claim 43, wherein the self-expanding material expands at a temperature of greater than about 30°

C.

61. The stent defined in claim 43, wherein said flexure structure, in two dimensions, has a width less than a width of said undulating circumferential portions.

62. The stent defined in claim 43, wherein adjacent undulating circumferential portions have substantially the same profile.

63. The stent defined in claim 43, wherein adjacent undulating circumferential portions have substantially different profiles.