ELASTOMERIC LEAFLET FOR PROSTHETIC HEART VALVES

• US 20140180402A1
• Filed: 02/17/2014
• Published: 06/26/2014
• Est. Priority Date: 04/01/2011
• Status: Active Grant

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Bruchman, William C., White, Charles F.
• Granted Patent: US 9,744,033 B2
• Time in Patent Office: Days
• US Class Current: 623/2.18
• CPC Class Codes: A61F 2/2415 Manufacturing methods
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61L 2420/04 Coatings containing a composite material such as inorganic/organic, i.e. material comprising different phases
• CPC Class Codes: A61L 2420/08 Coatings comprising two or more layers
• CPC Class Codes: A61L 2430/20 for reconstruction of the heart, e.g. heart valves
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: B29C 55/005 characterised by the choice of materials
• CPC Class Codes: B29C 61/02 Thermal shrinking
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

A leaflet for a prosthetic valve formed of at least one layer that includes a composite material containing at least one expanded fluoropolymer membrane having serpentine fibrils and an elastomer is provided. The fluoropolymer may be polytetrafluoroethylene. In at least one embodiment, the elastic properties are present in an axial direction the leaflet. The leaflets may be single layered or multi-layered. The leaflets may be coupled to a support structure and movable between open and closed configurations relative to the support structure to form a heart valve. The elasticity within the leaflets permits, among other things, the leaflets to bend with a reduced occurrence of wrinkles as the valve opens and closes. The elastic properties of the leaflet also, among other things, improve bending properties and reduce closure stresses, thereby extending the life of the leaflet.

Claims

1. A prosthetic valve, comprising:

a leaflet formed of at least one layer comprising a composite material including at least one expanded fluoropolymer membrane having serpentine fibrils and an elastomer.

2. The prosthetic valve of claim 1, wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

3. The prosthetic valve of claim 1, wherein the fluoropolymer is polytetrafluoroethylene.

4. The prosthetic valve of claim 1, wherein the leaflet has a ratio of thickness (μ

m) to number of layers of the composite material of less than about 5.

5. The prosthetic valve of claim 1, wherein the composite material is substantially free of wrinkles.

6. The prosthetic valve of claim 1, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

7. The prosthetic valve of claim 1, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

8. The prosthetic valve of claim 1, wherein elastic properties are present in an axial direction of the leaflet.

9. The prosthetic valve of claim 1, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

10. The prosthetic valve of claim 1, wherein the leaflet is operatively coupled to a support structure and is movable between closed and open configurations relative to the support structure.

11. An prosthetic valve, comprising:

a leaflet cyclable between a closed configuration to substantially prevent blood flow through the prosthetic valve and an open configuration to allow blood flow through the prosthetic valve, the leaflet including at least one layer comprising a composite material including at least one expanded fluoropolymer membrane having serpentine fibrils and an elastomer,

wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

12. The prosthetic valve of claim 11, wherein the composite material is substantially free of wrinkles.

13. The prosthetic valve of claim 11, wherein the fluoropolymer is polytetrafluoroethylene.

14. The prosthetic valve of claim 11, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

15. The prosthetic valve of claim 11, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

16. The prosthetic valve of claim 11, wherein the leaflet is operatively coupled to a support structure and is movable between the closed and open configurations relative to the support structure.

17. The prosthetic valve of claim 11, wherein the leaflet has a ratio of thickness (μ

m) to number of layers of the composite material of less than about 5.

18. The prosthetic valve of claim 11, wherein elastic properties are present in an axial direction of the leaflet.

19. The prosthetic valve of claim 11, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

20. A method of forming a leaflet of a prosthetic valve, comprising:

providing a composite material comprising at least one expanded fluoropolymer membrane having serpentine fibrils and an elastomer; and

bringing at least one layer of the composite material into contact with additional layers of the composite material by wrapping a sheet of the composite material with a starting and ending point defined as an axial seam adhered to itself.

21. The method of claim 20, wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

22. The method of claim 20, wherein the fluoropolymer is polytetrafluoroethylene.

23. The method of claim 20, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

24. The method of claim 20, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

25. The method of claim 20, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

26. A prosthetic valve, comprising:

a support structure; and

a leaflet formed of at least one layer comprising a composite material including at least one expanded fluoropolymer membrane having serpentine fibrils and an elastomer,

wherein the leaflet is movable between a closed configuration and an open configuration relative to the support structure, and

wherein the leaflet is cyclable between the closed configuration to substantially prevent blood flow through the prosthetic valve and the open configuration to allow blood flow through the prosthetic valve.

27. The prosthetic valve of claim 26, wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

28. The prosthetic valve of claim 26, wherein the composite material is substantially free of wrinkles.

29. The prosthetic valve of claim 26, wherein the fluoropolymer is polytetrafluoroethylene.

30. The prosthetic valve of claim 26, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

31. The prosthetic valve of claim 26, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

32. The prosthetic valve of claim 26, wherein elastic properties are present in an axial direction of the leaflet.

33. The prosthetic valve of claim 26, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

34. A prosthetic valve, comprising:

a leaflet formed of at least one layer comprising a composite material exhibiting an increase in stiffness when elongated to at least about 30% strain, the composite material including at least one expanded fluoropolymer membrane and an elastomer.

35. The prosthetic valve of claim 34, wherein the composite material exhibits an increase in stiffness when elongated to at least about 40% strain.

36. The prosthetic valve of claim 34, wherein the composite material exhibits an increase in stiffness when elongated to at least about 45% strain.

37. The prosthetic valve of claim 34, wherein the composite material exhibits an increase in stiffness when elongated to at least about 50% strain.

38. The prosthetic valve of claim 34, wherein the at least one expanded fluoropolymer membrane comprises serpentine fibrils.

39. The prosthetic valve of claim 38, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

40. The prosthetic valve of claim 38, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

41. The prosthetic valve of claim 34, wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

42. The prosthetic valve of claim 34, wherein the fluoropolymer is polytetrafluoroethylene.

43. The prosthetic valve of claim 34, wherein the leaflet has a ratio of thickness (μ

m) to number of layers of the composite material of less than about 5.

44. The prosthetic valve of claim 34, wherein the composite material is substantially free of wrinkles.

45. The prosthetic valve of claim 34, wherein elastic properties are present in an axial direction of the leaflet.

46. The prosthetic valve of claim 34, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

47. The prosthetic valve of claim 34, wherein the leaflet is operatively coupled to a support structure and is movable between closed and open configurations relative to the support structure.

48. A prosthetic valve, comprising:

a leaflet cyclable between a closed configuration to substantially prevent blood flow through the prosthetic valve and an open configuration to allow blood flow through the prosthetic valve, the leaflet including at least one layer comprising a composite material exhibiting an increase in stiffness when elongated to at least about 30% strain, the composite material including at least one expanded fluoropolymer membrane and an elastomer,

wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

49. The prosthetic valve of claim 48, wherein the composite material is substantially free of wrinkles.

50. The prosthetic valve of claim 48, wherein the fluoropolymer is polytetrafluoroethylene.

51. The prosthetic valve of claim 48, wherein the at least one expanded fluoropolymer membrane comprises serpentine fibrils.

52. The prosthetic valve of claim 48, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

53. The prosthetic valve of claim 48, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

54. The prosthetic valve of claim 48, wherein the leaflet is operatively coupled to a support structure and is movable between the closed and open configurations relative to the support structure.

55. A prosthetic valve, comprising:

a support structure; and

a leaflet formed of at least one layer comprising a composite material exhibiting an increase in stiffness when elongated to at least about 30% strain, the composite material including at least one expanded fluoropolymer membrane and an elastomer,

wherein the leaflet is movable between closed and open configurations relative to the support structure, and

wherein the leaflet is cyclable between the closed configuration to substantially prevent blood flow through the prosthetic valve and the open configuration to allow blood flow through the prosthetic valve.

56. The prosthetic valve of claim 55, wherein the expanded fluoropolymer membrane comprises a plurality of pores and the elastomer is present in substantially all of the pores.

57. The prosthetic valve of claim 55, wherein the composite material is substantially free of wrinkles.

58. The prosthetic valve of claim 55, wherein the fluoropolymer is polytetrafluoroethylene.

59. The prosthetic valve of claim 55, wherein the at least one expanded fluoropolymer membrane comprises serpentine fibrils.

60. The prosthetic valve of claim 55, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

61. The prosthetic valve of claim 55, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

62. The prosthetic valve of claim 55, wherein elastic properties are present in an axial direction of the leaflet.

63. The prosthetic valve of claim 55, wherein the elastomer is selected from the group consisting of perfluoromethylvinyl ether-tetrafluoroethylene copolymers, perfluoro (alkyl vinyl ether)-tetrafluoroethylene copolymers, silicones and polyurethanes.

64. A prosthetic valve, comprising:

a leaflet formed of at least one layer of a composite material including at least one expanded fluoropolymer membrane and an elastomer, the composite material being substantially free of wrinkles,

wherein the leaflet is operably configured to cycle between an open configuration and a closed configuration.

65. The prosthetic valve of claim 64, wherein the expanded fluoropolymer membrane comprises serpentine fibrils.

66. The prosthetic valve of claim 64, wherein the expanded fluoropolymer membrane comprises a microstructure of substantially only serpentine fibrils.

67. The prosthetic valve of claim 64, wherein the expanded fluoropolymer membrane comprises a plurality of serpentine fibrils.

68. The prosthetic valve of claim 64, wherein the fluoropolymer is polytetrafluoroethylene.