DEFFERENTIAL DILATION STENT AND METHOD OF USE

• US 20120239137A1
• Filed: 03/16/2012
• Published: 09/20/2012
• Est. Priority Date: 03/17/2011
• Status: Active Grant

• Current Assignee: PQ Bypass, Inc.
• Original Assignee: PQ Bypass, Inc.
• Inventors: Heuser, Richard R., Jambunathan, Kumar G.
• Granted Patent: US 9,301,830 B2
• Time in Patent Office: Days
• US Class Current: 623/1.16
• CPC Class Codes: A61F 2/07 Stent-grafts
• 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 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0037 differing in height or in length
• CPC Class Codes: A61F 2250/0039 differing in diameter

Abstract

Embodiments herein provide differential dilation stents for use in percutaneous interventions, such as transluminal bypass procedures. In some embodiments, the stents may be used in the process of creating an arteriovenous (AV) fistula during a percutaneous bypass procedure, and such stents may have two or more specialized regions that are configured to adopt a predetermined diameter, shape, and/or tensile strength upon insertion in order to suit the needs of the vessel or procedure. The disclosed stents may be used for creating and/or maintaining an arterial/venous fistula for bypass of an occlusion in a cardiac artery using a cardiac vein, or the femoral artery, for example using the tibial or popliteal vein.

Claims

1. A stent configured for insertion in a human blood vessel, the stent comprising:

a compressible, self-expanding, substantially cylindrical mesh body having an inside surface, an outside surface, a proximal end, and a distal end, wherein the inside and outside surfaces are coated with a flexible coating, and wherein the stent comprises at least two regions having different diameters when in an expanded state.

2. The stent of claim 1, wherein the flexible coating comprises PTFE.

3. The stent of claim 1, wherein the mesh body comprises nickel titanium alloy.

4. The stent of claim 1, wherein the at least two regions comprise a first region and a second region, and wherein the first region has a higher tensile strength than the second region.

5. The stent of claim 4, further comprising a third region having a greater tensile strength than the second region.

6. The stent of claim 5, wherein the distance from the proximal end to the distal end is from about 40 cm to about 150 cm.

7. The stent of claim 5, wherein the first region is from about 4 mm to about 9 mm in diameter and from about 10 cm to about 20 cm in length, wherein the second region is from about 6 mm to about 11 mm in diameter and from about 25 cm to about 45 cm in length, and wherein the third region is from about 2 mm to about 6 mm in diameter and from about 15 cm to about 25 cm in length.

8. The stent of claim 5, wherein the distance from the proximal end to the distal end is from about 35 cm to about 45 cm, wherein the first region is from about 6 mm to about 8 mm in diameter, and wherein the third region is from about 4 mm to about 6 mm in diameter.

9. The stent of claim 5, wherein the distance from the proximal end to the distal end is about 40 cm, wherein the first region is about 7 mm in diameter, and wherein the third region is about 5 mm in diameter.

10. The stent of claim 5, wherein the distance from the proximal end to the distal end is from about 55 cm to about 65 cm, wherein the first region is from about 5 mm to about 7 mm in diameter, and wherein the third region is from about 2 mm to about 4 mm in diameter.

11. The stent of claim 5, wherein the distance from the proximal end to the distal end is about 60 cm, wherein the first region is about 6 mm in diameter, and wherein the third region is about 3 mm in diameter.

12. The stent of claim 1, wherein the mesh body is biased toward an open position.

13. The stent of claim 1, wherein the mesh body is biased toward a curved position.

14. The stent of claim 13, wherein the curved position comprises a substantially S-shaped curve.

15. The stent of claim 13, wherein the curved position comprises two substantially S-shaped curves.

16. The stent of claim 15, wherein a first substantially S-shaped curve is located near the proximal end, and wherein a second substantially S-shaped curve is located near the distal end.

17. The stent of claim 1, wherein the mesh body comprises a plurality of serpentine rings arranged in a longitudinally successive pattern, said serpentine rings each comprising elongate struts joined by arcuate joints.

18. The stent of claim 17, wherein a terminal serpentine ring has a tail wire which is attached along its length to an adjacent strut.

19. The stent of claim 18, wherein the adjacent strut spans two serpentine rings and is attached to a second adjacent strut which spans a third ring.

20. The stent of claim 17, wherein at least some of the remaining adjacent serpentine rings maintain a longitudinal gap between ends of adjacent arcuate joints.

21. The stent of claim 1, wherein small holes are formed through the flexible coating.

22. The stent of claim 1, wherein the holes are laser drilled and have a diameter in the range from 5 microns to 30 microns.

23. The stent of claim 1, wherein at least one of the insider and the outside of the flexible coating comprises a drug.

24. The stent of claim 23, wherein the drug comprises heparin and the heparin is non-releasably formed on the flexible coating.

25. A stent configured for insertion in a human blood vessel, the stent comprising:

a compressible, self-expanding, substantially cylindrical nitinol mesh body having an inside surface, an outside surface, a proximal end, and a distal end, wherein the inside and outside surfaces are coated with a flexible PTFE coating, and wherein the stent comprises at least two regions having different diameters when in an expanded state, and wherein the at least two regions comprise a first region, a second region, and a third region, and wherein the first region and the third region have a higher tensile strength than the second region.

26. The stent of claim 25, wherein the mesh body is biased toward a curved position.

27. The stent of claim 25, wherein the distance from the proximal end to the distal end is about 40 cm, wherein the first region is about 7 mm in diameter, and wherein the third region is about 5 mm in diameter.

28. The stent of claim 25, wherein the distance from the proximal end to the distal end is about 60 cm, wherein the first region is about 6 mm in diameter, and wherein the third region is about 3 mm in diameter.