Stretchable anti-buckling coiled-sheet stent

• US 20040049258A1
• Filed: 08/08/2003
• Published: 03/11/2004
• Est. Priority Date: 11/16/1998
• Status: Active Grant

• Current Assignee: Farhad Khosravi, Himanshu N. Patel, John Spiridigliozzi
• Original Assignee: Farhad Khosravi, Himanshu N. Patel, John Spiridigliozzi
• Inventors: Spiridigliozzi, John, Khosravi, Farhad, Patel, Himanshu N.
• Granted Patent: US 7,179,284 B2
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/848 having means for fixation to the vessel wall, e.g. barbs
• 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 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• 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 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/065 Y-shaped blood vessels
• 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 2002/8486 provided on at least one of the ends
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0066 stapled
• 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 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0039 differing in diameter

Abstract

A stent-graft having an exo-skeleton attached to a tubular graft, the tubular graft having a peripheral wall defining a lumen therein extending between first and second ends. The exo-skeleton may assume contracted and enlarged conditions, and includes one or more serpentine elements, each extending both peripherally and axially along at least a portion of the peripheral wall. Coiled-sheet stents are provided on the ends of the tubular graft for anchoring the ends within a body passage. Each serpentine element is a zigzag structure extending peripherally about the peripheral wall, with a plurality of serpentine elements distributed axially along the peripheral wall. The serpentine elements are individually attached to the peripheral wall and/or connector elements may extend between adjacent serpentine elements. Alternatively, each serpentine element may define a generally sinusoidal shape extending axially along the peripheral wall. The tubular graft may have a bifurcated end from which a tubular graft extension segment may extend and to which a docking limb may be attached. A plurality of serpentine elements may also be attached to the extension segment and the docking limb.

Claims

1. A stent-graft, comprising:

a tubular graft having a peripheral wall defining a periphery and a lumen therein, the lumen extending axially between first and second ends of the tubular graft;

an exo-skeleton attached to the peripheral wall, the exo-skeleton comprising one or more serpentine elements, each serpentine element extending both peripherally and axially along at least a portion of the peripheral wall; and

a stent on the first end for substantially anchoring the first end within a body passage.

2. The stent-graft of claim 1, wherein each serpentine element comprises a zigzag structure extending substantially peripherally about the peripheral wall of the tubular graft.

3. The stent-graft of claim 2, further comprising a plurality of serpentine elements distributed axially along the peripheral wall for providing articulation of the tubular graft between adjacent serpentine elements.

4. The stent-graft of claim 3, wherein the plurality of serpentine elements are individually attached to the peripheral wall.

5. The stent-graft of claim 3, wherein the plurality of serpentine elements are connected to one another by one or more connector elements extending between adjacent serpentine elements.

6. The stent-graft of claim 1, wherein each serpentine element defines a generally sinusoidal shape extending substantially axially along the peripheral wall.

7. The stent-graft of claim 6, further comprising a plurality of serpentine elements distributed substantially evenly about the periphery of the peripheral wall.

8. The stent-graft of claim 6, wherein each serpentine element includes substantially transverse peripheral elements, adjacent transverse peripheral elements being connected by alternating curved elements, thereby defining the generally sinusoidal shape.

9. The stent-graft of claim 1, wherein the exo-skeleton is directable between a contracted condition for facilitating introduction within a body passage and an enlarged condition for deployment within the body passage, the exo-skeleton substantially supporting the tubular graft to hold the lumen of the tubular graft substantially open in the enlarged condition.

10. The stent-graft of claim 9, wherein the exo-skeleton is radially compressible to the contracted condition and biased to assume the enlarged condition.

11. The stent-graft of claim 9, wherein the contracted condition of the exo-skeleton is achieved by substantially flattening and circumferentially rolling the exo-skeleton.

12. The stent-graft of claim 1, wherein the tubular graft comprises a polymeric material.

13. The stent-graft of claim 1, wherein the polymeric material is selected from the group consisting of polyester, polytetrafluorethaline, dacron, teflon, and polyurethane.

14. The stent-graft of claim 1, wherein the exo-skeleton is attached to the tubular graft by sutures, staples, wires, or an adhesive.

15. The stent-graft of claim 1, wherein the exo-skeleton is attached to the tubular graft by a process selected from thermal bonding, chemical bonding, and ultrasonic bonding.

16. The stent-graft of claim 1, wherein the exo-skeleton comprises a flat-coiled sheet with the one or more serpentine elements formed therein.

17. The stent-graft of claim 1, wherein each serpentine element comprises a wire formed into a serpentine shape.

18. The stent-graft of claim 1, wherein the stent on the first end comprises a coiled-sheet stent.

19. The stent-graft of claim 1, wherein the stent includes external outwardly oriented hooks for engaging a wall of a body passage.

20. The stent-graft of claim 1, further comprising pro-thrombotic material on an exterior surface of at least the stent, or one of the first and second ends of the tubular graft.

21. The stent-graft of claim 1, wherein the first end of the tubular graft has a cross-section that is substantially smaller than a cross-section of the second end of the tubular graft.

22. The stent-graft of claim 1, wherein the exo-skeleton is attached to an exterior surface of the tubular graft.

23. A stent-graft, comprising:

a tubular graft having a peripheral wall defining a periphery and a lumen therein, the lumen extending axially between first and second ends of the tubular graft; and

a plurality of serpentine elements attached to and distributed axially along the peripheral wall in a predetermined configuration for providing articulation of the tubular graft between adjacent serpentine elements, each serpentine element defining a zigzag shape extending substantially peripherally about the peripheral wall of the tubular graft.

24. The stent-graft of claim 23, further comprising a stent on at least one of the first and second ends.

25. The stent-graft of claim 24, wherein the stent comprises a plurality of resilient mesh elements, the mesh elements being adapted to partially recoil when the stent is subjected to radially compressive forces.

26. The stent-graft of claim 25, wherein the entire stent is made of resilient mesh elements.

27. The stent-graft of claim 24, wherein the stent comprises a coiled-sheet stent.

28. The stent-graft of claim 27, wherein the coiled-sheet stent comprises a stretchable portion defined by a plurality of resilient mesh elements adapted to partially recoil when the stent is subjected to radially compressive forces.

29. The stent-graft of claim 28, wherein the stretchable portion extends longitudinally between first and second ends of the stent.

30. The stent-graft of claim 28, wherein the stretchable portion comprises a sleeve on an end of the coiled-sheet stent exposed beyond the respective end of the tubular graft.

31. The stent-graft of claim 23, wherein the plurality of serpentine elements are individually attached to the peripheral wall.

32. The stent-graft of claim 23, wherein the plurality of serpentine elements are connected to one another by one or more connector elements extending between adjacent serpentine elements.

33. The stent-graft of claim 23, wherein each serpentine element is directable between a contracted condition for facilitating introduction within a body passage and an enlarged condition for deployment within the body passage.

34. The stent-graft of claim 33, wherein each serpentine element is radially compressible to the contracted condition and biased to assume the enlarged condition.

35. The stent-graft of claim 23, wherein the second end of the tubular graft is bifurcated, and wherein the stent-graft further comprises:

a tubular graft extension segment extending from the second end, the tubular graft extension segment having a peripheral wall; and

a plurality of serpentine elements attached to and distributed along the peripheral wall of the tubular graft extension segment in a predetermined configuration for providing articulation of the tubular graft extension segment between adjacent serpentine elements.

36. The stent-graft of claim 35, further comprising:

a tubular graft docking limb having a peripheral wall, the docking limb being attachable to the second end of the tubular graft adjacent the tubular graft extension segment; and

a plurality of serpentine elements attached to and distributed along the peripheral wall of the tubular graft docking limb in a predetermined configuration for providing articulation of the tubular graft docking limb between adjacent serpentine elements.

37. A stent-graft for placement within a bifurcation, comprising:

a first tubular graft segment having a first end and a second bifurcated end, the first tubular graft segment having a first peripheral wall;

a second tubular graft segment extending from the second bifurcated end, the second tubular graft segment having a second peripheral wall; and

an exo-skeleton attached to at least one of the first and second peripheral walls, the exo-skeleton comprising one or more serpentine elements, each serpentine element extending both peripherally and axially along at least a portion of the respective peripheral wall to which it is attached.

38. The stent-graft of claim 37, further comprising a stent on the first end for substantially anchoring the first end within a body passage.

39. The stent-graft of claim 37, further comprising a stent on the second tubular graft segment opposite the second end of the first tubular graft segment.

40. The stent-graft of claim 37, further comprising a third tubular graft segment attachable to the second bifurcated end adjacent the second tubular graft segment, the third tubular graft segment having a third peripheral wall.

41. The stent-graft of claim 40, wherein the exo-skeleton comprises one or more serpentine elements attached to the third peripheral wall.

42. The stent-graft of claim 37, wherein the plurality of serpentine elements are individually attached to the respective peripheral wall.

43. The stent-graft of claim 37, wherein the plurality of serpentine elements are connected to one another by one or more connector elements extending between adjacent serpentine elements.

44. The stent-graft of claim 37, wherein each serpentine element is directable between a contracted condition for facilitating introduction within a body passage and an enlarged condition for deployment within the body passage.

45. The stent-graft of claim 44, wherein each serpentine element is radially compressible to the contracted condition and biased to assume the enlarged condition.

46. A method for repairing an aneurysm at a bifurcation between a first main vessel and second and third branch vessels, comprising the steps of:

percutaneously introducing a stent-graft into a vessel in a contracted condition, the stent-graft comprising a flexible exo-skeleton attached to a tubular graft;

advancing the stent-graft across the bifurcation between undiseased portions of the first and second vessels;

expanding the stent-graft to an enlarged condition, the exo-skeleton comprising serpentine elements retaining a lumen of the tubular graft substantially open;

occluding the third vessel proximate the bifurcation; and

implanting a bypass graft between the second and third vessel downstream from the bifurcation.

47. A stretchable stent, comprising:

a coiled-up sheet having overlapping inner and outer longitudinal sections, and being radially expandable between a first size and one or more larger sizes, the coiled-up sheet defining a periphery in a plane substantially perpendicular to a longitudinal axis thereof;

a plurality of teeth extending from the inner longitudinal section for engaging openings in the outer longitudinal section to selectively secure the coiled-up sheet in the one or more larger sizes; and

a stretchable portion comprising a plurality of resilient mesh elements extending along a portion of the coiled-up sheet, the mesh elements being adapted to partially recoil about the periphery of the coiled-up sheet when the stent is subjected to radially compressive forces.

48. The stent-graft of claim 47, wherein the stretchable portion extends longitudinally between first and second ends of the coiled-up sheet.

49. The stent-graft of claim 47, wherein the stretchable portion comprises a sleeve on an end of the coiled-up sheet.

50. The stent-graft of claim 47, wherein the coiled-up sheet comprises Nitinol.

51. The stent-graft of claim 50, wherein the coiled-up sheet is biased to adopt a second size larger than the first size when the Nitinol is in its austenitic phase, whereby the mesh elements define a stretched configuration about the periphery of the coiled-up sheet.

52. The stent-graft of claim 50, wherein the coiled-up sheet is biased to adopt a third size smaller than the second size when the Nitinol is in a martensitic phase, whereby the mesh elements define an unstretched configuration substantially smaller than the stretched configuration.

53. The stent-graft of claim 47, wherein the coiled-up sheet comprises an unstretchable portion that is generally incompressible about the periphery.