PARTIAL ENCAPSULATION OF STENTS USING STRIPS AND BANDS

• US 20010020181A1
• Filed: 09/29/1999
• Published: 09/06/2001
• Est. Priority Date: 02/02/1999
• Status: Active Grant

• Current Assignee: Bard Peripheral Vascular Incorporated (Becton, Dickinson & Co)
• Original Assignee: Bard Peripheral Vascular Incorporated (Becton, Dickinson & Co)
• Inventors: LAYNE, RICHARD
• Granted Patent: US 6,558,414 B2
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/89 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: Y10S 623/901 Method of manufacturing prosthetic device

Abstract

Partially encapsulated stents are made using strips and bands of covering material. In one embodiment ringed stents are placed over an inner ePTFE tube (e.g., supported on a mandrel) and are covered by a series of longitudinal strips. A series of spaced apart ePTFE circumferential bands can then be placed over the top of the longitudinal strips and ringed stents; alternatively bands alone or strips alone may be employed. All of the components of the structure are then laminated to the inner ePTFE tube to capture the stent. By selecting the size and position of the ePTFE bands, it is possible to leave critical parts of the stent unencapsulated to facilitate flexibility and expansion. The longitudinal strips can be woven about the stent and later laminated into position to provide an anti-compression function as well as overall structural stability. Although a single stent can be used, these approaches lend themselves to use of a plurality of individual ring stents spaced apart along the inner ePTFE tube.

Claims

1. A vascular graft, comprising:

a first expanded polytetrafluoroethylene layer;

a support layer comprising at least one stent, wherein said support layer is placed around said first expanded polytetrafluoroethylene layer; and

a second expanded polytetrafluoroethylene layer comprising a plurality of longitudinal strips.

2. The vascular graft of

claim 1

, wherein said second expanded polytetrafluoroethylene layer secures said support layer to said first expanded polytetrafluoroethylene layer and wherein portions of the support layer remain exposed.

3. The vascular graft of

claim 1

, further comprising a third expanded polytetrafluoroethylene layer comprising a plurality of circumferential bands spaced so that portions of the support layer are exposed.

4. The vascular graft of

claim 3

, wherein said second and third expanded polytetrafluoroethylene layers secure said support layer to said first expanded polytetrafluoroethylene layer.

5. The vascular graft of

claim 1

, wherein said support layer comprises a plurality of ringed stents.

6. The vascular graft of

claim 5

, wherein said ringed stents are formed in a zigzag pattern of alternating peaks and valleys.

7. The vascular graft of

claim 6

, wherein said zigzag ringed stents are placed around said first expanded polytetrafluoroethylene layer with the alternating peaks and valleys in phase.

8. The vascular graft of

claim 1

, wherein said stent is made of metal.

9. The vascular graft of

claim 5

, wherein said longitudinal strips of material are alternatingly woven over and under each successive ringed stent.

10. The vascular graft of

claim 9

, wherein said longitudinal strips of material are cut from a distal end of said first expanded polytetrafluoroethylene layer of material with a proximal end of said longitudinal strips attached to said first expanded polytetrafluoroethylene layer of material.

11. The vascular graft of

claim 9

, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

12. The vascular graft of

claim 10

, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

13. The vascular graft of

claim 1

, wherein both a proximal and a distal end of said vascular graft are fully encapsulated.

14. A vascular graft, comprising:

a first expanded polytetrafluoroethylene layer;

a support layer comprising at least one stent, wherein said support layer is placed around said first expanded polytetrafluoroethylene layer; and

a second expanded polytetrafluoroethylene layer comprising a plurality of circumferential bands spaced so that portions of the support layer are exposed.

15. The vascular graft of

claim 14

, wherein said second expanded polytetrafluoroethylene layer secures said support layer to said first expanded polytetrafluoroethylene layer.

16. The vascular graft of

claim 14

, further comprising a third expanded polytetrafluoroethylene layer comprising a plurality of longitudinal strips of material.

17. The vascular graft of

claim 16

, wherein said second and third expanded polytetrafluoroethylene layers secure said support layer to said first expanded polytetrafluoroethylene layer.

18. The vascular graft of

claim 14

, wherein said support layer comprises a plurality of ringed stents.

19. The vascular graft of

claim 18

, wherein said ringed stents are formed in a zigzag pattern of alternating peaks and valleys.

20. The vascular graft of

claim 19

, wherein said zigzag ringed stents are placed around said first expanded polytetrafluoroethylene layer with the alternating peaks and valleys in phase.

21. The vascular graft of

claim 14

, wherein said stent is made of metal.

22. The vascular graft of

claim 16

, wherein said longitudinal strips of material are alternatingly woven over and under each successive ringed stent.

23. The vascular graft of

claim 22

, wherein said longitudinal strips of material are cut from a distal end of said first expanded polytetrafluoroethylene layer of material with a proximal end of said longitudinal strips attached to said first expanded polytetrafluoroethylene layer of material, and wherein a distal end of said longitudinal strips is alternatingly woven over and under each successive ringed stent.

26. The vascular graft of

claim 14

, wherein both a proximal and a distal end of said vascular graft are fully encapsulated.

24. The vascular graft of 22, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

25. The vascular graft of 23, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

27. A vascular graft, comprising:

a first expanded polytetrafluoroethylene layer;

a support layer comprising at least one stent with said support layer placed around said first expanded polytetrafluoroethylene layer;

a second expanded polytetrafluoroethylene layer comprising a plurality of longitudinal strips of material; and

a third expanded polytetrafluoroethylene layer comprising a plurality of circumferential bands spaced apart to cover a portion of an outer surface of the at least one stent, wherein said second and third expanded polytetrafluoroethylene layers secure said support layer to said first expanded polytetrafluoroethylene layer.

28. The vascular graft of

claim 27

, wherein said support layer comprises a plurality of ringed stents.

29. The vascular graft of

claim 28

, wherein said ringed stents are formed in a zigzag pattern of alternating peaks and valleys.

30. The vascular graft of

claim 29

, wherein said zigzag ringed stents are placed around said first expanded polytetrafluoroethylene layer with the alternating peaks and valleys in phase.

31. The vascular graft of

claim 27

, wherein said at least one stent is made of metal.

32. The vascular graft of

claim 27

, wherein said longitudinal strips of material are alternatingly woven over and under each successive ringed stent.

33. The vascular graft of

claim 32

, wherein said longitudinal strips of material are cut from a distal end of said first expanded polytetrafluoroethylene layer of material with a proximal end of said longitudinal strips attached to said first expanded polytetrafluoroethylene layer of material.

36. The vascular graft of

claim 27

, wherein both a proximal and a distal end of said vascular graft are fully encapsulated.

34. The vascular graft of 32, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

35. The vascular graft of 33, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

37. A vascular graft, comprising:

a first expanded polytetrafluoroethylene layer of material;

a support layer having a plurality of ringed stents evenly spaced, wherein said support layer is placed around said first expanded polytetrafluoroethylene layer; and

a second expanded polytetrafluoroethylene layer comprising a plurality of longitudinal strips of material that are alternatingly woven over and under each successive ringed stent; and

a third expanded polytetrafluoroethylene layer comprising a plurality of circumferential bands spaced apart to cover a portion of an outer surface of the at least one stent, wherein said second and third expanded polytetrafluoroethylene layers secure said support layer to said first expanded polytetrafluoroethylene layer.

38. The vascular graft of

claim 37

, wherein said longitudinal strips of material are cut from a distal end of said first expanded polytetrafluoroethylene layer of material, wherein a proximal end of said longitudinal strips is attached to said first expanded polytetrafluoroethylene layer of material.

41. The vascular graft of

claim 37

, wherein said ringed stents are formed in a zigzag pattern of alternating peaks and valleys.

42. The vascular graft of

claim 41

, wherein said zigzag ringed stents are placed over said first expanded polytetrafluoroethylene layer with the alternating peaks and valleys of successive stents in phase.

43. The vascular graft of

claim 37

, wherein said ringed stents are made of metal.

44. The vascular graft of

claim 37

, wherein both a proximal and a distal end of said vascular graft are fully encapsulated.

39. The vascular graft of 37, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

40. The vascular graft of 38, wherein a first longitudinal strip is woven over a first ringed stent, wherein a second longitudinal strip, adjacent to said first longitudinal strip, is woven under a first ringed stent, and wherein each successive adjacent odd numbered longitudinal strip is woven over a first ringed stent and each successive adjacent even numbered longitudinal strip is woven under a first ringed stent.

45. A method for making a partially encapsulated vascular graft, comprising:

providing a generally tubular expanded polytetrafluoroethylene layer of material;

placing a support layer comprised of a plurality of ringed stents over said tubular layer;

cutting a plurality of slits in a terminal portion of said tubular layer not covered by said stents, resulting in a plurality of longitudinal strips;

weaving said longitudinal strips alternatingly over and under each successive ringed stent, wherein a first longitudinal strip is woven over a first ringed stent, and wherein a second longitudinal strip is woven under the first ringed stent; and

laminating said longitudinal strips to said tubular layer.

46. The method of

claim 45

, further comprising the step of placing a plurality of expanded polytetrafluoroethylene circumferential bands over said support layer before said laminating step, wherein said plurality of circumferential bands are spaced apart so that each said circumferential band covers a portion of an outer surface of said ringed stents.

47. The method of

claim 45

, further comprising the step of fully encapsulating both a proximal and a distal end of said vascular graft.

48. The method of

claim 45

, wherein said ringed stents are formed in a zigzag pattern of alternating peaks and valleys and wherein said placing step further comprises placing said peaks and valleys of successive stents in phase.