DIFFERENTIAL DILATION STENT AND METHOD OF USE

• US 20160175087A1
• Filed: 02/25/2016
• Published: 06/23/2016
• 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
• Granted Patent: US 10,182,902 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 bent wire formed into a cylindrical body comprising a plurality of serpentine rings including a terminal ring at one end of the body and an adjacent ring inward from the terminal ring, wherein each serpentine ring comprises a plurality of axial struts, wherein circumferentially adjacent axial struts are joined by arcuate joints and wherein each serpentine ring has an inside surface, an outside surface, a proximal end, and a distal end, and wherein at least some of the axially adjacent serpentine rings other than the terminal ring and inward ring maintain a longitudinal gap between ends of adjacent arcuate joints.

2. The stent of claim 1, wherein the terminal ring ends in a tail strut and at least one strut in the terminal ring other than other than the tail strut is longer than all other struts in the terminal ring and has a length sufficient to span the terminal ring and the adjacent ring inward from the terminal ring to create an overlap which enhances the strength of the ends of the body.

3. The stent of claim 2, further comprising a flexible coating including at least one sheet or membrane covering the inside and outside surfaces of at least some of the serpentine rings in order to encapsulate the body.

4. The stent of claim 3, wherein the flexible coating fully encapsulates the cylindrical body.

5. The stent of claim 4, wherein an end of the flexible coating is scalloped so that the coating terminates in an undulating pattern which matches the pattern of the terminal ring.

6. The stent of claim 3, wherein the flexible coating comprises polyethylene terephthalate (PTFE).

7. The stent of claim 1, wherein the bent wire comprises nickel titanium alloy.

8. The stent of claim 1, wherein the bent wire is formed into a continuous helical structure with only one distal end and one proximal end.

9. The stent of claim 1, wherein the cylindrical body has a length in the range from about 40 cm to about 150 cm.

10. The stent of claim 1, wherein the cylindrical body is self-expanding and biased toward an open position.

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

12. The stent of claim 11, wherein the curved position comprises a substantially S-shaped curve.

13. The stent of claim 11, wherein the curved position comprises two substantially S-shaped curves.

14. The stent of claim 13, 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.

15. The stent of claim 1, wherein the tail strut in the terminal ring is attached along its length to the at least one adjacent strut.

16. The stent of claim 15, wherein the at least one adjacent strut in the terminal ring extends axially to the adjacent ring and is attached to a strut in the adjacent ring which spans a third ring.

17. The stent of claim 3, wherein small holes are formed through the flexible coating.