Interior liner for tubes, pipes and blood conduits

• US 5,800,522 A
• Filed: 01/24/1997
• Issued: 09/01/1998
• Est. Priority Date: 07/07/1995
• Status: Expired due to Term

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Kovach, Larry J., Mayrand, Mark E., Kasic, James F. II, Laguna, Alvaro J., Zukowski, Stanislaw L., Campbell, Carey V., Myers, David J., Lewis, James D.
• Primary Examiner(s): Milano, Michael J.
• Application Number:
  US08/789,378
• Time in Patent Office: 585 Days
• Field of Search: 623/1, 623/11, 623/12
• US Class Current: 128/898
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/30289 helically-coiled
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• 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 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: B29C 48/00 Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor extrusion blow-moulding B29C49/04
• CPC Class Codes: B29C 48/0012 combined with shaping by internal pressure generated in the material, e.g. foaming
• CPC Class Codes: B29C 48/0021 combined with joining, lining or laminating
• CPC Class Codes: B29C 48/07 Flat, e.g. panels
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/15 incorporating preformed parts or layers, e.g. extrusion moulding around inserts
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 53/58 helically
• CPC Class Codes: B29C 55/24 : radial
• CPC Class Codes: B29C 63/34 : using tubular layers or sheathings
• CPC Class Codes: B29K 2027/18 : PTFE, i.e. polytetrafluorethene , e.g. ePTFE, i.e. expanded polytetrafluorethene
• CPC Class Codes: B29K 2105/04 : cellular or porous
• CPC Class Codes: B29K 2995/0072 : Roughness, e.g. anti-slip
• CPC Class Codes: B29L 2023/007 : Medical tubes other than catheters catheters B29L2031/7542
• CPC Class Codes: F16L 11/12 : with arrangements for particular purposes, e.g. specially profiled, with protecting layer, heated, electrically conducting F16L11/11 takes precedence

Abstract

A tube which circumferentially distends from its initial circumference upon the application of a circumferentially distending force such as applied by an internal pressure, and which exhibits minimal recoil following the removal of the circumferentially distending force. The tube preferably has a second circumference larger than the initial circumference which remains substantially unchanged by further increasing force once it has been achieved. Because of the distensible circumference and minimal recoil of the tube, the tube is useful as a liner for pipes and vessels and particularly for pipes and vessels having irregular internal surfaces to which the tube can smoothly conform. The tube is preferably made from porous PTFE with thin walls, in which form it is particularly useful as a liner for both living and prosthetic blood vessels and to line anastomoses between living and prosthetic blood vessels. The tube or any other intraluminal graft may be used in in situ bypass procedures to hold venous valves open and to occlude tributary branches. Covered stents may be used for the same purpose; stents without such a covering may also be used to hold venous valves open.

Claims

1. A method of performing an in situ bypass, comprising:

a. creating a vein segment;

b. inserting a circumferentially distensible intraluminal graft into the vein segment and into at least one venous valve within the vein segment;

c. circumferentially distending the intraluminal graft, thereby holding open the at least one venous valve; and

d. anastomosing the vein segment to adjacent arteries.

2. A method according to claim 1 wherein the intraluminal graft also occludes at least one tributary to the vein.

3. A method according to claim 1 wherein the intraluminal graft holds open at least two venous valves.

4. A method according to claim 1 wherein the intraluminal graft is comprised of porous PTFE.

5. A method according to claim 4 wherein the intraluminal graft has a first circumference prior to distension and wherein the intraluminal graft has a second, larger circumference resulting from distension by the application of internal pressure.

6. A method according to claim 4 wherein the intraluminal graft has a wall thickness of less than about 0.25 mm.

7. A method according to claim 6 wherein the intraluminal graft has a wall thickness of less than about 0.10 mm.

8. A method according to claim 5 wherein the intraluminal graft has a wall thickness of less than about 0.25 mm.

9. A method according to claim 8 wherein the intraluminal graft has a wall thickness of less than about 0.10 mm.

10. A method according to claim 5 wherein the intraluminal graft exhibits minimal recoil of 14 percent or less.

11. A method according to claim 10 wherein the intraluminal graft exhibits minimal recoil of 10 percent or less.

12. A method according to claim 11 wherein the intraluminal graft exhibits minimal recoil of 7 percent or less.

13. A method according to claim 5 wherein the porous PTFE intraluminal graft comprises an inner layer having a microstructure with axially oriented fibrils and at least one outer layer having a microstructure with helically oriented fibrils.

14. A method according to claim 5 wherein the internal pressure is the result of the use of a liquid.

15. A method according to claim 14 wherein the liquid is chosen from the group consisting of water, saline and blood.

16. A method according to claim 2 wherein the intraluminal graft holds open leaflets of at least two venous valves.

17. A method according to claim 2 wherein the intraluminal graft is comprised of porous PTFE.

18. A method according to claim 17 wherein the intraluminal graft has a first circumference prior to distension and wherein the intraluminal graft has a second, larger circumference resulting from distension by the application of internal pressure.

19. A method according to claim 17 wherein the intraluminal graft has a wall thickness of less than about 0.25 mm.

20. A method according to claim 19 wherein the intraluminal graft has a wall thickness of less than about 0.10 mm.

21. A method according to claim 18 wherein the intraluminal graft has a wall thickness of less than about 0.25 mm.

22. A method according to claim 21 wherein the intraluminal graft has a wall thickness of less than about 0.10 mm.

23. A method according to claim 5 wherein the intraluminal graft has first and second opposing ends and wherein the second circumference at the first opposing end is larger than the second circumference at the second opposing end.

24. A method of holding leaflets of a venous valve in an open condition, comprising inserting a circumferentially distensible tubular article into a segment of a vein and into a venous valve within the vein, and circumferentially distending the tubular article, thereby holding open the leaflets of the venous valve.

25. A method according to claim 24 wherein the segment of a vein has a length and the tubular article extends for the length of the segment of the vein.

26. A method according to claim 24 wherein the tubular article is an intraluminal graft.

27. A method according to claim 26 wherein the intraluminal graft is comprised of porous PTFE.

28. A method according to claim 24 wherein the tubular article is a stent.

29. A method according to claim 28 wherein the stent is provided with a covering of graft material.