Grafts and Stents Having Inorganic Bio-Compatible Calcium Salt

• US 20110076315A1
• Filed: 06/08/2006
• Published: 03/31/2011
• Est. Priority Date: 06/08/2005
• Status: Abandoned Application

• Current Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Original Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Inventors: Pathak, Chandrashekhar P., Casanova, R. Michael
• Application Number:
  US11/916,813
• Publication Number:
  US 20110076315A1
• Time in Patent Office: Days
• US Class Current: 424/423
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61L 2300/104 Silver, e.g. silver sulfadiazine
• CPC Class Codes: A61L 2300/404 Biocides, antimicrobial agents, antiseptic agents
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 27/14 Macromolecular materials
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 31/04 Macromolecular materials
• CPC Class Codes: A61L 31/086 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: A61L 31/10 Macromolecular materials
• CPC Class Codes: A61L 31/146 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: A61P 31/00 Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
• CPC Class Codes: A61P 35/00 Antineoplastic agents
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

The present application discusses techniques and structures that incorporate calcium salts in the luminal surface of grafts. In an embodiment, a graft, stent-graft or TIPS may incorporate bio-compatible calcium salt, which is essentially non-osteoinductive in nature, on the surfaces of the implantable device.

Claims

1. A graft device comprising:

a layer of synthetic non-metallic material having a first surface and a second surface spaced apart from the first surface; and

an inorganic bio-compatible calcium salt coupled to at least one of the first and second surfaces of the synthetic non-metallic material.

2. The graft device according to claim 1, wherein the synthetic non-metallic material comprises a material selected from a group consisting essentially of Dacron, polyester, PTFE, ePTFE, polyurethane, polyurethane-urea, siloxane, and combinations thereof.

3. The graft device according to claim 1, wherein the synthetic non-metallic material comprises ePTFE having internodal distance of about 10 microns to about 40 microns and a porosity of about 5 microns to about 100 microns.

4. The graft device according to claim 2, wherein the layer of ePTFE comprises an average thickness of about 40 to 300 microns.

5. The graft device according to claim 1, wherein the synthetic non-metallic material comprises ePTFE and the bio-compatible calcium salt comprises hydroxyapatite having particles with an average size of about 20 nanometers to about 100 microns.

6. The graft device according to claim 1, wherein the inorganic bio-compatible calcium salt comprises a calcium to phosphorus ratio from about 1.2 to about 1.7.

7. The graft device according to claim 1, wherein the inorganic bio-compatible calcium salt comprises porous hydroxyapatite coupled to at least one biologically active agent.

8. The graft device according to claim 7, wherein the at least one biologically active agent is selected from a group consisting essentially of antibiotics, anti-renosis agents, anti-proliferative agents, and combinations thereof.

9. The graft device according to claim 8, wherein the anti-restenosis agents comprise one of paclitaxel and rapamycin.

10. The graft device according to claim 9, wherein at least one of the ePTFE layer and the hydroxyapatite includes a layer of silver chloride.

11. The graft device according to claim 2, further comprising a stent frame work having a portion of the frame work encapsulated by the synthetic non-metallic material.

12. The graft device according claim 1 further comprising a flared end portion defining a generally elliptical perimeter being coupled to the graft device.

13. The graft device of claim 1, wherein the inorganic bio-compatible calcium salt is impregnated with the synthetic non-metallic material.

14. The graft device of claim 1, wherein the inorganic biocompatible calcium salt is encapsulated in the synthetic non-metallic material.

15. The graft device of claim 1, wherein the inorganic biocompatible calcium salt is encapsulated by the synthetic non-metallic material.

20. The implant device according to claim 1, wherein the layer of ePTFE comprises an average thickness of about 40 to 300 microns.

27. The method of claim 20, wherein the expanding comprises sintering the tubular member.

16. An implant device comprising:

a stent frame;

a synthetic non-metallic material that surrounds a portion of the stent frame, the synthetic non-metallic material having first and second surfaces; and

an inorganic bio-compatible calcium salt coupled to at least one of the first and second surfaces of the synthetic non-metallic material.

17. The implant device according to claim 16, wherein the synthetic non-metallic material comprises a material selected from a group consisting essentially of Dacron, polyester, PTFE, ePTFE, polyurethane, polyurethane-urea, siloxane, and combinations thereof.

18. The implant device according to claim 16, wherein the synthetic non-metallic material comprises ePTFE having internodal distance of about 10 microns to about 40 microns.

19. The implant device according to claim 16, wherein the ePTFE comprises a plurality of layers of ePTFE.

21. A method of endothiealizing a graft comprising:

coupling a synthetic non-metallic material with inorganic bio-compatible calcium salt to form a composite graft device; and

implanting the composite graft device in body vessel of a mammal.

22. The method of claim 21, wherein the coupling comprises sputtering the inorganic bio compatible calcium salt on at least one surface of the synthetic non-metallic material.

23. The method of claim 21, wherein the coupling comprises spraying the inorganic bio compatible calcium salt on at least one surface of synthetic non-metallic material.

24. The method of claim 23, wherein the coupling comprises providing ePTFE.

25. The method of claim 24, wherein the coupling comprises extruding the inorganic bio compatible calcium salt as a layer with at least one layer of ePTFE to form a tubular member having a first length.

26. The method of claim 25, wherein the extruding comprises expanding the tubular member to about 50% of the first length.

28. A method of making a composite graft comprising:

providing a non-metallic material;

providing inorganic bio-compatible calcium salt; and

coupling inorganic bio-compatible calcium salt to the non-metallic material.

29. The method of claim 28, wherein the non-metallic material comprises a synthetic fiber.

30. The method of claim 29, wherein the synthetic fiber is selected from a group of material consisting essentially of Dacron, polyester, PTFE, ePTFE, polyurethane, polyurethane-urea, siloxane, and combinations thereof.

31. The method of claim 28, wherein the coupling comprises extruding the PTFE and hydroxyapatite.

32. The method of claim 28, wherein the coupling comprises forming at least one layer of PTFE coupled to at least one layer of hydroxyapatite.

33. The method of claim 28, wherein the extruding comprises expanding the PTFE to provide for expanded PTFE.

34. The method of claim 28, further comprising sintering the PTFE and hydroxyapatite.

35. The method of claim 28, wherein the non-metallic material comprises ePTFE having internodal distance of about 10 microns to about 40 microns and a porosity of about 5 microns to about 100 microns.

36. The graft device of claim 28, wherein the layer of ePTFE comprises an average thickness of about 40 to 300 microns.

37. The graft device of claim 28, wherein the non-metallic material comprises ePTFE and the hydroxyapatite includes particles having an average size of about 20 nanometers to about 100 microns.

38. The graft device of claim 28, wherein the hydroxyapatite comprises a calcium to phosphorus ratio from about 1.2 to about 1.7.

39. The graft device of claim 28, wherein the inorganic bio-compatible calcium salt comprises porous hydroxyapatite coupled to at least one biologically active agent.

40. The graft device according to claim 39, wherein the at least one biologically active agent is selected from a group consisting essentially of antibiotics, anti-renosis agents, anti proliferative agents, and combinations thereof.

41. A graft, comprising:

a first layer forming a first surface including an admixture of polymeric material and calcium salt;

a second layer including expanded polymeric material joined with the first layer.

42. A graft as in claim 41, wherein the polymeric material includes ePTFE having internodal distance of about 10 microns to about 41 microns and a porosity of about 5 microns to about 100 microns.

43. A graft as in claim 41, wherein the second layer has an average thickness of about 41 to 300 microns.

44. A graft as in claim 41, wherein the second layer is porous.

45. A graft as in claim 41, wherein the admixture is of polytetrafluoroethylene and hydroxyapatite.

46. A graft as in claim 41, wherein the first layer defines a lumen and the second layer surrounds the first layer.

47. A graft as in claim 41, wherein the first layer defines an annular flow channel.

48. A method of forming a graft, comprising:

forming a billet from an admixture of divided bio-compatible calcium salt and a divided non-metallic material;

extruding the billet.

49. The method as in claim 48, further comprising enveloping a stent with an extrudate formed by extruding the billet.

50. The method as in claim 49, wherein the calcium salt includes hydroxyapatite.

51. The method as in claim 48, wherein the forming includes mixing the calcium salt with a resin and a lubricant.

52. The method as in claim 48, wherein the non-metallic material includes polytetrafluoroethylene.

53. The method as in claim 52, wherein the calcium salt includes hydroxyapatite.

54. The method as in claim 48, wherein the billet includes an admixture layer of calcium salt mixed with polymeric material and an annular layer surrounding the admixture layer of polymeric material;

the extruding including coextruding the billet.

55. The method as in claim 54, wherein the extruding includes forming a tubular structure.

56. The method as in claim 55, further comprising expanding the extrudate resulting from the extruding.

57. The method as in claim 56, wherein the expanding includes sintering.

58. The method as in claim 48, further comprising expanding the extrudate resulting from the extruding.

59. The method as in claim 58, wherein the expanding includes sintering.