COLLAPSIBLE STENT

• US 20100211163A1
• Filed: 06/05/2008
• Published: 08/19/2010
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: University Hospitals of Leicester N H S Trust
• Original Assignee: University Hospitals of Leicester N H S Trust
• Inventors: Gershlick, Anthony Harvey
• Granted Patent: US 8,876,887 B2
• Time in Patent Office: Days
• US Class Current: 623/1.180
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• 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 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2002/821 Ostial stents
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity

Abstract

A stent suitable for the repair of lesions in bifurcated blood vessels is provided, having a deformable end portion such that a free end of the end portion can be aligned with the surface of an abutting stent or angioplasty balloon in a main branch of the bifurcated vessel. A method of blood vessel repair using this stent is also provided.

Claims

1. A stent comprising an end portion which, in an expanded state, defines a vessel-supporting wall having a free end defining a circumference at the free end;

wherein the end portion is deformable to longitudinally collapse the vessel-supporting wall at a first point on the circumference by a larger amount than at a second point.

2. A stent as claimed in claim 1, in which the free end defines a free end plane and wherein the end portion is deformable to dispose the end plane in a tilted relationship with the vessel-supporting wall.

3. A stent as claimed in claim 2, in which the free end is arranged to yield to an uneven pressure on it to the tilted relationship.

4. A stent as claimed in claim 2, in which the free end is arranged to yield when pressed on by a surface which is tilted with respect to the vessel-supporting wall to an attitude in which the end plane is generally aligned with the surface.

5. A stent as claimed in claim 2, in which, when the end plane is tilted, a projection of the free end on to a cross-section of the vessel-supporting wall substantially coincides with the cross section of the vessel-supporting wall.

6. A stent as claimed in claim 1, in which the end portion defines a concertina-like arrangement.

7. A stent as claimed in claim 1, in which the end portion includes a ring secured by a collapsible web.

8. A stent as claimed in claim 7, in which the ring is expandable.

9. A stent as claimed in claim 8, in which the ring is arranged to expand and the web is arranged to collapse when the end portion is deformed to longitudinally collapse the vessel-supporting wall at the first point by a larger amount than at the second point.

10. A stent as claimed in claim 7, in which the ring is folded up within the vessel-supporting wall.

11. A stent as claimed claim 7, in which the web is arranged to fold onto itself when collapsing.

12. A stent as claimed in claim 11, in which the web is arranged to fold onto itself within the vessel-supporting wall.

13. A stent as claimed in claim 11, in which the web is arranged to fold onto itself such as to protrude from the vessel-supporting wall out of the end portion.

14. A stent as claimed in claim 7, in which the end portion includes a plurality of expandable rings secured to each other by collapsible webs.

15. A stent as claimed in claim 1, in which the end portion defines a spiral.

16. A stent as claimed in claim 15, in which the spiral has a plurality of turns joined by collapsible webs.

17. A stent as claimed in claim 1, further including a main portion for supporting a vessel, the end portion being secured to the main portion.

18. A stent as claimed in claim 17, in which the main portion and the end portion are manufactured from a single tubular member by machining away material to define the main and end portions.

19. A stent as claimed in claim 17, in which the main portion and the end portion are manufactured separately and joined.

20. A stent as claimed in claim 1, in which the end portion is constrained by a sheath in its unexpanded state and is expandable by withdrawing the sheath.

21. A stent as claimed in claim 20, in which the end portion comprises a shape memory alloy.

22. A method of repairing a bifurcated blood vessel including the steps of:

placing a stent as claimed in claim 1 in a side branch of the bifurcated vessel;

shaping the end portion of the stent to conform substantially to an ostium between the side branch and a main branch of the bifurcated vessel.

23. A method as claimed in claim 22 in which shaping includes positioning a further stent in the main branch of the bifurcated vessel opposite the side branch and expanding the further stent against the stent in the side branch, thereby placing the further stent.

24. A method as claimed in claim 23, further including backing off a balloon catheter used to expand the further stent, introducing the catheter into the side branch and expanding the catheter, thereby aligning the end portion of the stent in the side branch with an opening in the stent in the main branch.

25. A method as claimed in claim 22, in which placing the stent includes expanding the stent by withdrawing a sheath.

26. A method as claimed in claim 22, in which placing the stent includes expanding the stent by inflating a balloon within the stent.

27. A method as claimed in claim 22, which includes placing a further stent in the side branch adjacent to the stent placed in the side branch.