Tissue material and process for bioprosthesis

• US 20070005132A1
• Filed: 09/05/2006
• Published: 01/04/2007
• Est. Priority Date: 11/26/2002
• Status: Active Grant

• Current Assignee: Clemson University
• Original Assignee: Clemson University
• Inventors: Vyavahare, Narendra, Simionescu, Dan
• Granted Patent: US 7,753,840 B2
• Time in Patent Office: Days
• US Class Current: 623/2.140
• CPC Class Codes: A61F 2/2412 with soft flexible valve members, e.g. tissue valves shaped like natural valves check valves with flexible valve members in general F16K15/14
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: Y10S 623/909 Method or apparatus for assembling prosthetic

Abstract

A biomaterial useful for bioprostheses such as bioprosthetic heart valves is provided in which the fixed tissue has improved elastic properties. The high elastin-containing biomaterial is further characterized by having anisotropic properties wherein the biological material has a greater stiffness in one direction and a greater elasticity in a cross direction. For instance, the biological material has an elastin content of about 30% by weight. In one embodiment, the biological material is vena cava tissue.

Claims

1-15. -15. (canceled)

16. A process for forming a bioprosthesis comprising:

providing a flat tissue having an elastin content of at least about 10%;

excising a portion of the flat tissue; and

attaching the portion to a support material of the bioprosthesis.

17. The process of claim 16, wherein the flat tissue is an anisotropic material, and the excised portion of the flat tissue exhibits greater stiffness in a first direction and greater elasticity in a second direction.

18. The process of claim 17, wherein the excised portion of the flat tissue is formed in the shape of a heart valve leaflet, the direction of greater elasticity of the excised portion being substantially equivalent to the center-most radius of the heart valve leaflet.

19. The process of claim 17, wherein the excised portion of the flat tissue is formed in the shape of a heart valve leaflet.

20. The process of claim 19, wherein the heart valve leaflet is a tricuspid valve leaflet.

21. The process of claim 19, wherein the heart valve leaflet is a bicuspid valve leaflet.

22. The process of claim 16, wherein the bioprosthesis is a bioprosthetic heart valve.

23. The process of claim 16, wherein the support material comprises a suture ring.

24. The process of claim 16, wherein the flat tissue is vena cava tissue.

25. The process of claim 24, further comprising obtaining a section of vena cava, and opening the section of vena cava with a longitudinal incision to form a flat tissue.

26. The process of claim 24, wherein the vena cava is porcine vena cava.

27. The process of claim 16, further comprising chemically fixing the tissue.

28. A process for replacing a damaged cardiac valve comprising:

surgical removal of a damaged cardiac valve from the heart of a patient;

implantation of a bioprosthetic heart valve in the cardiac valve annulus, wherein the bioprosthetic heart valve comprises a fixed tissue having an elastin content of at least about 10% by weight of the tissue and a support structure selected from the group consisting of a suture ring and a stent; and

attachment of the bioprosthetic heart valve to the tissue of the cardiac valve annulus.

29. The process of claim 28, wherein the tissue has an elastin content of at least about 30% by weight of the tissue.

30. The process of claim 28, wherein the tissue is vena cava tissue.

31. The process of claim 30, wherein the tissue is porcine vena cava tissue.

32. The process of claim 28, wherein the bioprosthetic heart valve is a tricuspid heart valve.

33. The process of claim 28, wherein the bioprosthetic heart valve is a bicuspid heart valve.

34. A bioprosthesis comprising:

a fixed natural tissue having an elastin content of at least about 30% by weight of the tissue; and

a support structure comprising a metallic material wherein the support structure is attached to the fixed natural tissue.

35. The bioprosthesis of claim 34, wherein the tissue is an anisotropic tissue.

36. The bioprosthesis of claim 35, wherein the anisotropic tissue exhibits greater stiffness in a first direction and greater elasticity in a second direction.

37. The bioprosthesis of claim 34, wherein the tissue is vena cava tissue.

38. The bioprosthesis of claim 37, wherein the vena cava tissue is porcine vena cava tissue.

39. The bioprosthesis of claim 34, wherein the support structure is a stent.

40. The bioprosthesis of claim 34, wherein the support structure is a suture ring.