Covered endoprosthesis and delivery system

• US 20020198588A1
• Filed: 06/21/2002
• Published: 12/26/2002
• Est. Priority Date: 01/22/1999
• Status: Active Grant

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: Edward H. Cully, Joseph R. Armstrong, Margaret L. Gallegos, Michael J. Vonesh
• Inventors: Cully, Edward H., Armstrong, Joseph R., Vonesh, Michael J., Gallegos, Margaret L.
• Granted Patent: US 7,056,336 B2
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

The present invention is an improved endovascular device particularly useful for use in transjugular intrahepatic portosystemic shunt (TIPS) procedures. The device employs a two-part stent-graft construction that provides a low permeability membrane to line the shunt and an uncovered stent portion designed to reside in the portal vein. The device provides numerous benefits over previous stents and stent-grafts used in TIPS procedures, including being more compact to deliver, being easier to accurately deploy, a controlled compacted surface with tucked apices, an improved stent winding pattern, and being more flexible in delivery and use.

Claims

1. An endoprosthesis comprising

a stent element;

a cover on at least a portion of the stent element, the cover comprising a fluoropolymer and the cover having a low permeability characterized by a permeability measurement of greater than 70 seconds per 100 cc air per 1 cm² of material.

2. The endoprosthesis of claim 1 wherein the cover includes a stored length.

3. The endoprosthesis of claim 1 wherein the cover comprises expanded polytetrafluoroethylene.

4. The endoprosthesis of claim 3 wherein the stent element includes at least a first segment and a second segment, and wherein the cover is attached to only the first segment.

5. The endoprosthesis of claim 4 wherein the second segment includes an interlocked stent pattern that resists uncontrolled elongation.

6. The endoprosthesis of claim 1 wherein the cover includes a structure having stored length, assisting the covered first segment in bending without kinking.

7. The endoprosthesis of claim 1 wherein the endoprosthesis is delivered at a compacted diameter and the endoprosthesis self-expands to an enlarged deployed diameter.

8. The endoprosthesis of claim 7 wherein the stent element is folded into multiple pleats in its compacted diameter.

9. The endoprosthesis of claim 8 wherein

the stent element comprises a series of forward facing and rearward facing undulations;

and

one series of undulations is folded within the pleats.

10. The endoprosthesis of claim 7 wherein the endoprosthesis at its compacted diameter is no more than 12 French.

11. The endoprosthesis of claim 1 wherein the stent element has a radial stiffness of at least 0.1 kg/mm of diameter with a 1 cm wide loop test.

12. The endoprosthesis of claim 1 wherein the cover has a thickness of no more than 0.4 mm.

14. The endoprosthesis of claim 13 wherein the cover includes a stored length.

15. The endoprosthesis of claim 13 wherein the cover comprises expanded polytetrafluoroethylene.

16. The endoprosthesis of claim 15 wherein the stent element includes at least a first segment and a second segment, and wherein the cover is attached to only the first segment.

17. The endoprosthesis of claim 16 wherein the second segment includes an interlocked stent pattern that resists uncontrolled elongation.

18. The endoprosthesis of claim 13 wherein the cover includes a structure having stored length, assisting the covered first segment in bending without kinking.

19. The endoprosthesis of claim 13 wherein the endoprosthesis is delivered at a compacted diameter and the endoprosthesis self-expands to an enlarged deployed diameter.

20. The endoprosthesis of claim 19 wherein the stent element is folded into multiple pleats in its compacted diameter.

21. The endoprosthesis of claim 20 wherein

the stent element comprises a series of forward facing and rearward facing undulations;

and

one series of undulations is folded within the pleats.

22. The endoprosthesis of claim 19 wherein the endoprosthesis at its compacted diameter is no more than 12 French.

23. The endoprosthesis of claim 13 wherein the stent element has a radial stiffness of at least 0.1 kg/mm of diameter with a 1 cm wide loop test.

24. The endoprosthesis of claim 13 wherein the cover has a thickness of no more than 0.4 mm.

13. An endoprosthesis comprising

a stent element;

a cover on at least a portion of the stent element, the cover comprising a fluoropolymer and the cover having a low permeability characterized by a permeability measurement of greater than 60 seconds per 100 cc air per 1 cm² of material.