Bioprosthesis and method for suturelessly making same

• US 20030181974A1
• Filed: 03/21/2002
• Published: 09/25/2003
• Est. Priority Date: 03/21/2002
• Status: Active Grant

• Current Assignee: Providence Health System - Oregon
• Original Assignee: Providence Health System - Oregon
• Inventors: Xie, Hua, Buckley, Lisa A.
• Granted Patent: US 7,163,556 B2
• Time in Patent Office: Days
• US Class Current: 623/1.24
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2475 Venous valves
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0026 trapezoidal

Abstract

A bioprosthetic valve graft comprises a valve frame and valve flaps, the latter acting to open or close a valve aperture to directionally control fluid flow through the bioprosthesis. The bioprosthetic valve graft comprises a biomaterial suturelessly bonded to the valve frame, avoiding sutures and substantially reducing medical complications in implantations.

Claims

1. A valve graft adapted to be implanted in a patient, comprising:

a valve frame defining a valve frame open area; and

a sheet of biomaterial suturelessly attached to said valve frame and spanning said valve frame open area.

2. The valve graft of claim 1, wherein said sheet is small intestine submucosa.

3. The valve graft of claim 2, wherein said sheet is substantially comprised of collagen.

4. The valve graft of claim 1, wherein said sheet is constructed to a selected thickness.

5. The valve graft of claim 1, wherein said sheet has an aperture across a short axis of the valve frame open area.

6. The valve graft of claim 1, wherein said valve frame consists of shape memory material.

7. The valve graft of claim 1, wherein said valve is adapted to be vascularly implanted.

8. The valve graft of claim 1, wherein said valve is adapted to be intraluminally implanted.

9. The valve graft of claim 1, wherein said valve is adapted to be implanted in a heart.

10. A method for producing a sutureless valve graft suitable for physiological implantation, comprising:

positioning a flexible valve frame defining an open area on a first major surface of a biomaterial sheet having a peripheral edge, said positioning serving to approximate the valve frame and the peripheral edge of the biomaterial sheet to form an at least first bonding locus; and

suturelessly bonding the biomaterial to the valve frame at the at least first bonding locus.

11. The method of claim 10, wherein positioning comprises:

positioning the valve frame on the first major surface of the biomaterial sheet; and

folding the edge of the biomaterial sheet over the valve frame so that the edge of the biomaterial sheet is contacted with the first major surface of the biomaterial sheet.

12. The method of claim 10, wherein suturelessly bonding comprises suturelessly bonding the edge of the biomaterial sheet directly to the valve frame.

13. The method of claim 10, further comprising:

applying a distorting force to the valve frame to distort the valve frame into a flexed state prior to positioning the valve frame; and

releasing the distorting force after suturelessly bonding.

14. The method of claim 10, wherein the biomaterial sheet consists essentially of small intestine submucosa.

15. The method of claim 10, wherein suturelessly bonding comprises irradiating the at least first bonding locus with energy sufficient to at least partially fuse the portion of the approximated biomaterial sheet to attach the biomaterial to the valve frame at the at least first bonding locus.

16. The method of claim 15, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with light.

17. The method of claim 16, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with light generated by a laser.

18. The method of claim 17, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with light having a wavelength of about 800 nm.

19. The method of claim 18, further comprising introducing a chromophore that is energy-absorptive at about 800 nm.

20. The method of claim 10, further comprising introducing a photo-chemical crosslinking agent.

21. The method of claim 20, wherein said photo-chemical crosslinking agent is methylene blue.

22. The method of claim 21, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with white light.

23. The method of claim 21, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with ultraviolet light.

24. The method of claim 15, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with radio-frequency energy.

25. The method of claim 15, wherein irradiating the at least first bonding locus with energy comprises irradiating the at least first bonding locus with ultrasound energy.

26. The method of claim 10, further comprising creating an aperture across a short axis of the biomaterial sheet.

27. The method of claim 10, further comprising dehydrating the biomaterial prior to suturelessly bonding;

and rehydrating the biomaterial after suturelessly bonding.

28. The method of claim 10, further comprising securing the valve frame in the flexed state by attaching a diametric suture, wherein releasing the distorting force comprises removing the diametric suture.

29. A method for suturelessly attaching a collagen-rich biomaterial sheet to a prosthesis frame element, comprising:

approximating a portion of the biomaterial sheet to the prosthesis frame element to define an at least first bonding locus;

irradiating the at least first bonding locus with energy from an energygenerating source, said energy sufficient to at least partially fuse the portion of the approximated biomaterial sheet.

30. The method of claim 29, wherein irradiating the at least first bonding locus with energy from an energy-generating source comprises irradiating the at least first bonding locus with energy from a radio-frequency device.

31. The method of claim 29, wherein irradiating the at least first bonding locus with energy from an energy-generating source comprises irradiating the at least first bonding locus with energy from an ultrasound device.

32. The method of claim 29, wherein irradiating the at least first bonding locus with energy from an energy-generating source comprises irradiating the at least first bonding locus with light energy from a laser.

33. The method of claim 32, wherein said laser emits light having a wavelength of about 800 nm.

34. The method of claim 32, further comprising introducing a chromophore.

35. The method of claim 34, wherein said chromophore is indocyanine green.

36. The method of claim 29, wherein irradiating the at least first bonding locus with energy from an energy-generating source comprises contacting the at least first bonding locus with a contact thermoelectric transducer.

37. The method of claim 29, further comprising dehydrating the biomaterial prior to bonding;

and rehydrating the biomaterial after bonding.

38. The method of claim 29, wherein the prosthesis frame element comprises a synthetic material.

39. The method of claim 29, wherein the prosthesis frame element comprises a biomaterial.

40. The method of claim 29, wherein the biomaterial consists essentially of collagen.

41. The method of claim 29, wherein the biomaterial substantially comprises small intestine submucosa.

42. A method for implanting a sutureless valve graft in a patient, comprising:

providing a sutureless valve graft including a valve frame defining a valve frame open area and a biomaterial sheet being suturelessly attached to said valve frame and spanning said valve frame open area;

flexing the valve graft into a folded state;

introducing the folded valve graft to an implantation site in the patient;

unflexing the valve graft to at least partially unfold same at the implantation site.

43. The method of claim 42, wherein flexing the valve graft comprises folding the valve frame to compress the valve graft into an elongate shape having an aspect ratio greater than 1:

1.

44. The method of claim 42, wherein said flexing is performed substantially perpendicular to an aperture in the biomaterial sheet.

45. The method of claim 42, wherein introducing the folded valve graft is via a catheter.