Self-sealing PTFE vascular graft and manufacturing methods

• US 6,428,571 B1
• Filed: 03/14/2000
• Issued: 08/06/2002
• Est. Priority Date: 01/22/1996
• Status: Expired due to Term

• Current Assignee: Lifeport Sciences LLC (Acacia Research Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Henderson, Jamie, Sowinski, Krzysztof, Rakos, Ronald, Lentz, David, Zdrahala, Richard, Dormier, Edward, Loomis, Gary
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): GHERBI, SUZETTE JAIME J
• Application Number:
  US09/525,710
• Time in Patent Office: 875 Days
• Field of Search: 623/1.15, 623/1.27, 623/1.39, 623/1.4, 623/1.49
• US Class Current: 623/1.4
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61L 27/16 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/507 for artificial blood vessels apparatus for applying cells on a blood vessel prosthesis A61F2/062
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

An implantable microporous ePTFE tubular vascular graft exhibits long term patency, superior radial tensile strength and suture hole elongation resistance. The graft includes a first ePTFE tube and a second ePTFE tube circumferentially disposed over the first tube. The first ePTFE tube exhibits a porosity sufficient to promote cell endothelization, tissue ingrowth and healing. The second ePTFE tube exhibits enhanced radial strength in excess of the radial tensile strength of the first tube.

Claims

1. An ePTFE self-sealing graft comprising:

a first ePTFE tubular structure having a first porosity;

a second ePTFE tubular structure having a second porosity less than said first porosity, said second ePTFE tubular structure being disposed externally about said first ePTFE tubular structure; and

a resealable polymer layer interposed between said first and second ePTFE tubular structures.

2. An ePTFE self-sealing graft according to claim 1 wherein said resealable polymer layer comprises an elastomeric layer.

3. An ePTFE self-sealing graft according to claim 2 wherein said resealable polymer layer adheres to said first and second ePTFE tubular structures.

4. An ePTFE self-sealing graft according to claim 2 wherein said elastomeric polymer layer is a fluoropolymer.

5. An ePTFE self-sealing graft according to claim 2 wherein said elastomeric polymer layer comprises a helically wound tape.

6. An ePTFE self-sealing graft according to claim 2 wherein said elastomeric polymer layer comprises a silicon compound.

7. An ePTFE self-sealing graft according to claim 1 wherein said resealable polymer layer comprises a flowable layer.

8. An ePTFE self-sealing graft according to claim 7 wherein said resealable polymer layer comprises a polymer which penetrates said first and second ePTFE tubular structures.

9. An ePTFE self-sealing graft according to claim 7 wherein said resealable polymer layer adheres to said first and second ePTFE tubular structures.

10. An ePTFE self-sealing graft according to claim 7 wherein said resealable layer is a fluoropolymer.

11. An ePTFE self-sealing graft according to claim 7 wherein said flowable layer comprises a gel.

12. An ePTFE self-sealing graft according to claim 11 wherein said gel further includes comprises polymeric beads suspended within said gel.

13. An ePTFE self-sealing graft according to claim 7 wherein said flowable polymer layer comprises a silicon compound.

14. An ePTFE self-sealing graft according to claim 7 wherein said flowable polymer layer comprises an uncured polymer.

15. An ePTFE self-sealing graft according to claim 7 wherein said flowable polymer comprises a partially cured polymer.

16. A method of forming a tubular vascular prosthesis comprising the steps of:

providing a first ePTFE tubular structure having a given porosity sufficient to promote cell endothelization and a given strength;

providing a second ePTFE tubular structure having a radial strength greater than the radial strength of said first ePTFE tubular structure;

disposing an intermediate resealable polymer layer over said first ePTFE tubular structure; and

disposing said second ePTFE tubular structure over said intermediate layer to define a composite structure.

17. A method according to claim 16 wherein said resealable polymer layer comprises an elastomeric layer.

18. A method according to claim 17 wherein said resealable polymer layer adheres to said first and second ePTFE tubular structures.

19. A method according to claim 17 wherein said elastomeric polymer layer is a fluoropolymer.

20. A method according to claim 17 wherein said elastomeric polymer layer comprises a helically wound tape.

21. A method according to claim 17 wherein said elastomeric polymer layer comprises a silicon compound.

22. A method according to claim 16 wherein said resealable polymer layer comprises a flowable layer.

23. A method according to claim 22 wherein said flowable layer comprises a polymer which penetrates said first and second ePTFE tubular structures.

24. A method according to claim 22 wherein said flowable layer adheres to said first and second ePTFE tubular structures.

25. A method according to claim 22 wherein said flowable layer is a fluoropolymer.

26. A method according to claim 22 wherein said flowable layer comprises a gel.

27. An ePTFE self-sealing graft comprising:

a first ePTFE tubular structure;

a second ePTFE tubular structure disposed externally about said first ePTFE tubular structure; and

a self-sustained resealable polymer layer interposed between said first and second ePTFE tubular structures.