Fracture-resistant helical stent incorporating bistable cells and methods of use

• US 8,353,948 B2
• Filed: 03/29/2006
• Issued: 01/15/2013
• Est. Priority Date: 01/24/1997
• Status: Expired due to Fees

• Current Assignee: CeloNova Stent, Inc.
• Original Assignee: CeloNova Stent, Inc.
• Inventors: Besselink, Petrus Antonius, Bates, Mark C.
• Primary Examiner(s): Hughes, S. Thomas
• Assistant Examiner(s): TANNER, JOCELIN C
• Application Number:
  US11/391,940
• Publication Number:
  US 20060217795A1
• Time in Patent Office: 2,484 Days
• Field of Search: 623/1.15, 623/1.11, 623/1.16, 623/1.38, 623/1.46, 623/1.22, 623/1.18, 623/1.2, 623/1.34, 623/1.42
• US Class Current: 623/1.15
• CPC Class Codes: A61B 17/11 for performing anastomosis; Buttons for anastomosis
• CPC Class Codes: A61F 2/064 with special features to facilitate anastomotic coupling anastomosis of natural blood vessels A61B17/11
• 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 2002/91541 Adjacent bands are arranged out of phase

Abstract

Vascular prostheses and methods of use are provided, wherein the vascular prosthesis includes a plurality of bistable unit cells configured to form a helical structure. A visualization catheter also is provided for use ensuring accurate measurement of a lesion and ensuring delivery and placement of the vascular prosthesis.

Claims

1. A prosthesis comprising a helical body having a plurality of turns, the plurality of turns comprising unit cells interconnected by bridge elements, one or more of the unit cells having a thin strut including first and second ends coupled to a thick strut having a thickness that is greater than a thickness of the thin strut, the thin strut configured to transition between only a stable fully collapsed configuration and a stable fully expanded configuration, wherein:

for each unit cell, the first and second ends of the thin strut are coupled with corresponding first and second sections of the thick strut; and

the thin strut is stable in only the fully collapsed configuration or the fully expanded configuration such that there are no stable states between the fully collapsed configuration and the fully expanded configuration;

wherein the unit cells are arranged such that the first ends and sections of the thin and thick struts respectively are distal of the second ends and sections of the thin and thick struts respectively.

2. The prosthesis of claim 1 further comprising at least one terminal turn, the terminal turn including additional unit cells that define an annular structure when the prosthesis is deployed.

3. The prosthesis of claim 2 wherein at least some of the additional unit cells are bistable cells.

4. The prosthesis of claim 1 wherein the thin strut has a first thickness and the thick strut has a second thickness, and a ratio of the first thickness to the second thickness is between 1:

2 and 1;

5.

5. The prosthesis of claim 1 wherein the thin strut and the thick strut are elongated in a direction parallel to a longitudinal axis of the helical body.

6. The prosthesis of claim 1, wherein the first end of the thin strut is coupled to the thick strut at a distal end of the unit cell and the second end of the thin strut is coupled to the thick strut at a proximal end of the unit cell, the proximal ends of the unit cells of one turn of the helical body being disposed adjacent to the distal ends of the unit cells of an adjacent turn of the helical body when the prosthesis is deployed.

7. The prosthesis of claim 6 wherein a pitch of the helical body is selected so that a gap is formed between the proximal ends of the unit cells of at least one turn of the helical body and the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

8. The prosthesis of claim 7 wherein the pitch of the helical body is selected so that the proximal ends of the unit cells of one turn of the helical body are circumferentially offset from the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

9. The prosthesis of claim 6 wherein a pitch of the helical body is selected so that a gap is formed between the proximal ends of the unit cells of at least two turns of the helical body and the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

10. The prosthesis of claim 1 wherein the thin strut and the thick strut each has an arcuate shape.

11. The prosthesis of claim 1 wherein each bridge element connects a thin strut of one unit cell to a thick strut of an adjacent unit cell.

12. The prosthesis of claim 1 further comprising one or more radiopaque markers affixed to the helical body.

13. The prosthesis of claim 1 wherein the helical body further comprises a bioactive agent or drug coating.

14. The prosthesis of claim 1 wherein the helical body comprises a shape memory material.

15. The prosthesis of claim 1 wherein the helical body comprises a biodegradable material.

16. The prosthesis of claim 1 wherein the thin strut of at least one of the unit cells comprises a plurality of generally rigid interconnected members.

17. The prosthesis of claim 1 wherein the thin strut of at least one of the unit cells comprises one or more hinges.

18. The prosthesis of claim 1 wherein the thin strut of at least one of the unit cells comprises three generally linear portions, the three generally linear portions cumulatively forming a generally arcuate shape.

19. A kit for treating occlusive disease in a body vessel, the kit comprising:

a prosthesis comprising a helical body extending along a longitudinal axis and having a plurality of turns, the plurality of turns comprising unit cells interconnected by bridge elements, each of the unit cells having a thin strut including first and second ends coupled to a thick strut having a thickness that is greater than a thickness of the thin strut, the thin strut configured to transition between only a stable fully collapsed configuration and a stable fully expanded configuration, wherein;

for each unit cell, the first and second ends of the thin strut are coupled with corresponding first and second sections of the thick strut, the second section being proximal of the first section; and

the thin strut is stable in only the fully collapsed configuration or the fully expanded configuration such that there are no stable states between the fully collapsed configuration and the fully expanded configuration; and

a visualization catheter comprising an elongated body having a proximal end and a distal end and a guide wire lumen extending therethrough, a tapered portion disposed near the distal end and one or more radiopaque markers disposed on the tapered portion.

20. The kit of claim 19 wherein the visualization catheter further comprises an injection port, one or more outlet ports, and a second lumen extending between the injection port and the one or more outlet ports.

21. The kit of claim 20 wherein the one or more outlet ports are disposed near the tapered portion.

22. The kit of claim 19 wherein the distal end of the elongated body is articulable.

23. The kit of claim 19 wherein the thin strut has a first thickness and the thick strut has a second thickness, and a ratio of the first thickness to the second thickness is between 1:

2 and 1;

5.

24. The kit of claim 23 wherein the thin strut and the thick strut are elongated in a direction parallel to a longitudinal axis of the helical body.

25. The kit of claim 19 wherein the first end of the thin strut is coupled to the thick strut at a distal end of the unit cell and the second end of the thin strut is coupled to the thick strut at a proximal end of the unit cell, the proximal ends of the unit cells of one turn of the helical body being disposed adjacent to the distal ends of the unit cells of an adjacent turn of the helical body when the prosthesis is deployed.

26. The kit of claim 25 wherein a pitch of the helical body is selected so that a gap is formed between the proximal ends of the unit cells of one turn of the helical body and the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

27. The kit of claim 26 wherein the pitch of the helical body is selected so that the proximal ends of the unit cells of one turn of the helical body are circumferentially offset from the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

28. The kit of claim 19 wherein the thin strut and the thick strut each has an arcuate shape.

29. The kit of claim 19 wherein the helical body further comprises a bioactive agent or drug coating.

30. The prosthesis of claim 19 wherein the unit cells are interconnected by bridge elements extending in a helical direction.

31. A prosthesis comprising a helical body having a plurality of turns, the plurality of turns comprising unit cells, each of the unit cells comprising a thin portion having first and second ends directly attached to first and second ends of a thick portion having a thickness that is greater than a thickness of the thin portion, the thin portion configured to transition between a stable collapsed configuration wherein at least a portion of the thin portion is generally concave and a stable expanded configuration wherein at least a portion of the thin portion is generally convex, and wherein a distance that extends from the first end to the second end of the thin portion is approximately the same in the stable collapsed configuration and the stable expanded configuration.

32. The prosthesis of claim 31 wherein one or more of the unit cells are bistable cells.

33. The prosthesis of claim 31 further comprising at least one terminal turn, the terminal turn including additional unit cells comprising an annular structure when the prosthesis is deployed.

34. The prosthesis of claim 31 wherein the first end of the thin portion is coupled to the thick portion at a distal end of the unit cell, the proximal ends of the unit cells of one turn of the helical body disposed adjacent to the distal ends of the unit cells of an adjacent turn of the helical body when the prosthesis is deployed.

35. The prosthesis of claim 34 wherein a pitch of the helical body is selected so that a gap is formed between the proximal ends of the unit cells of one turn of the helical body and the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

36. The prosthesis of claim 35 wherein the pitch of the helical body is selected so that the proximal ends of the unit cells of one turn of the helical body are circumferentially offset from the distal ends of the unit cells of the adjacent turn of the helical body when the prosthesis is deployed.

37. The prosthesis of claim 31 wherein at least a portion of the thin portion is generally arcuate.

38. The prosthesis of claim 31 wherein the thin portion of at least one of the unit cells comprises a plurality of generally rigid interconnected members.

39. The prosthesis of claim 31 wherein the thin strut of at least one of the unit cells comprises one or more hinges.

40. The prosthesis of claim 31 wherein the thin strut of at least one of the unit cells comprises three generally linear portions, the three generally linear portions cumulatively forming a generally arcuate shape.

41. The prosthesis of claim 31 wherein the unit cells are interconnected by bridge elements extending in a helical direction.

42. A prosthesis comprising a helical body having a plurality of turns, the plurality of turns comprising unit cells interconnected by bridge elements, each of the unit cells comprising a thin strut having first and second ends coupled to a thick strut having a thickness that is greater than a thickness of the thin strut,

the thin strut configured to move from a stable collapsed configuration under outwardly directed radial force to a transition point at which no additional force is needed to further move the thin strut to a stable expanded position such that the thin strut transitions between a stable collapsed configuration and at least one stable expanded configuration, and wherein a distance between the first and second ends of the thin strut is approximately the same in the stable collapsed configuration and the stable expanded configuration;

and

a continuous helically oriented gap is formed between the proximal ends of the unit cells of at least one turn of the helical body and the distal ends of the unit cells of an adjacent turn of the helical body along at least a substantial portion of the length of the prosthesis when the prosthesis is deployed.

43. The prosthesis of claim 42 wherein one or more of the unit cells are bistable cells.

44. The prosthesis of claim 42 wherein the continuous helically oriented gap is formed between the proximal ends of the unit cells of at least two turns of the helical body and the distal ends of the unit cells of the adjacent turns of the helical body when the prosthesis is deployed.

45. The prosthesis of claim 42 wherein the continuous helically oriented gap extends along the entire length of the helical body.

46. The prosthesis of claim 42 further comprising at least one terminal turn, the terminal turn including additional unit cells that define an annular structure when the prosthesis is deployed.

47. The prosthesis of claim 42 further comprising a first and a second end portion each comprising a terminal turn, wherein each terminal turn includes additional unit cells that define an annular structure when the prosthesis is deployed and wherein the continuous helically oriented gap extends along the portion of the length of the helical body between the end portions.

48. The prosthesis of claim 42 wherein the first end of the thin strut is coupled to the thick strut at a distal end of the unit cell and the second end of the thin strut is coupled to the thick strut at a proximal end of the unit cell, the proximal ends of the unit cells of one turn of the helical body disposed adjacent to the distal ends of the unit cells of an adjacent turn of the helical body when the prosthesis is deployed.

49. The prosthesis of claim 42 wherein the unit cells are interconnected by bridge elements extending in a helical direction.

50. A prosthesis comprising a helical body having a plurality of turns, the plurality of turns comprising unit cells interconnected by bridge elements, each of the unit cells having a generally longitudinal wave-like thin strut including first and second ends coupled to a generally longitudinal wave-like thick strut having a thickness that is greater than a thickness of the thin strut, the thin strut configured to transition between a stable fully collapsed configuration wherein the thin strut and the thick strut are generally in phase and a stable fully expanded configuration wherein the thin strut and the thick strut are generally out of phase, wherein a distance between the first and second ends of the thin strut is approximately the same in the stable fully collapsed configuration and the stable fully expanded configuration, and

wherein the unit cell is configured to permit the thin strut to transition from the stable fully collapsed configuration to the stable fully expanded configuration without requiring the prosthesis to absorb heat.

51. The prosthesis of claim 50 wherein the thin strut of at least one of the unit cells comprises three generally linear portions, the three generally linear portions cumulatively forming a generally wave-like shape.