Endoluminal prosthesis and system for joining

• US 6,117,167 A
• Filed: 02/09/1998
• Issued: 09/12/2000
• Est. Priority Date: 02/09/1994
• Status: Expired due to Term

• Current Assignee: Lifeport Sciences LLC (Acacia Research Corporation)
• Original Assignee: Boston Scientific Technology Incorporated (Boston Scientific Corporation)
• Inventors: Goicoechea, George, Hudson, John, Mialhe, Claude, Cragg, Andrew H., Dake, Michael D.
• Primary Examiner(s): Milano, Michael J.
• Application Number:
  US09/020,749
• Time in Patent Office: 946 Days
• Field of Search: 623/1, 623/11, 623/12, 623/1.16
• US Class Current: 623/1.16
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/852 Two or more distinct overlapping stents
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/954 for placing stents or stent-grafts in a bifurcation
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/061 provided with means for allowing access to secondary lumens
• CPC Class Codes: A61F 2002/065 Y-shaped blood vessels
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/828 Means for connecting a plurality of stents allowing flexibility of the whole structure
• CPC Class Codes: A61F 2002/8486 provided on at least one of the ends
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• 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 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• 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 2230/0067 conical
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61M 25/0662 : Guide tubes
• CPC Class Codes: Y10S 623/903 : Blood vessel
• CPC Class Codes: Y10T 29/49826 : Assembling or joining

Abstract

A stent joining means is provided for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents. The stent joining means includes two transversely spaced female portions on the first endoluminal stent. The stent joining means also includes a male engaging portion of the second endoluminal stent. The male engaging portion is configured to be entered into one of the female portions in a radially compressed state and thereafter expanded in the female portion such that an outer surface of the male engaging portion and an inner surface of the female portion are interengaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

Claims

1. A stent joining means for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

a male engaging portion on said first endoluminal stent which has an outer surface and can be compressed radially inwardly, wherein said male engaging portion is flared radially outwardly towards a proximal end; and

a female portion on said second endoluminal stent cooperating with said male engaging portion, said female portion having an inner surface;

wherein said first endoluminal stent and said second endoluminal stent consist of a shape memory alloy and the male engaging portion can be entered into the female portion in a radially compressed state and thereafter expanded in the female portion and wherein said outer surface of the male engaging portion and said inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

2. A stent joining means for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

a male engaging portion on said first endoluminal stent which has an outer surface and can be compressed radially inwardly; and

a female portion on said second endoluminal stent cooperating with said male engaging portion, said female portion having an inner surface, wherein the female portion is tapered radially inwardly towards a distal end;

wherein said first endoluminal stent and said second endoluminal stent consist of a shape memory alloy and the male engaging portion can be entered into the female portion in a radially compressed state and thereafter expanded in the female portion and wherein said outer surface of the male engaging portion and said inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

3. A stent joining means for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

a male engaging portion on said first endoluminal stent which has an outer surface and can be compressed radially inwardly, wherein the male engaging portion comprises a frustoconical wall flaring outwardly towards a longitudinal extremity; and

a female portion on said second endoluminal stent cooperating with said male engaging portion, said female portion having an inner surface;

wherein said first endoluminal stent and said second endoluminal stent consist of a shape memory alloy and the male engaging portion can be entered into the female portion in a radially compressed state and thereafter expanded in the female portion and wherein said outer surface of the male engaging portion and said inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

4. A stent joining means for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

male engaging portion on said first endoluminal stent which has an outer surface and can be compressed radially inwardly; and

a female portion on said second endoluminal stent cooperating with said male engaging portion, said female portion having an inner surface, wherein the female portion comprises a frustoconical wall tapering radially inwardly towards a longitudinal extremity;

wherein said first endoluminal stent and said second endoluminal stent consist of a shape memory alloy and the male engaging portion can be entered into the female portion in a radially compressed state and thereafter expanded in the female portion and wherein said outer surface of the male engaging portion and said inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

5. A stent joining means for adjoining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

a male engaging portion on said first endoluminal stent which has an outer surface and can be compressed radially inwardly; and

two transversely spaced female portions on said second endoluminal stent, at least one female portion on said second endoluminal stent cooperating with said male engaging portion, said female portion having an inner surface;

wherein said first endoluminal stent and said second endoluminal stent consist of a shape memoru alloy and the male engaging portion can be entered into the female portion in a radially compressed state and thereafter expanded in the female portion and wherein said outer surface of the male engaging portion and said inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service.

6. A stent joining means as claimed in claim 5, at least one of said stents having a taper to resist longitudinal separation of said stents in service.

7. A stent joining means as claimed in claim 5, at least one of said stents having a flare to engage the body lumen.

8. A stent joining means as claimed in claim 5, further comprising a graft layer associated with said female portion, said male engaging portion providing a substantially blood tight seal with said graft layer.

9. A stent joining means as claimed in claim 5, said male engaging portion being flared when uncompressed.

10. A stent joining means as claimed in claim 5, wherein said second endoluminal stent is adapted to extend across a bifurcation in a blood vessel such that in use a proximal end of said second endoluminal stent is disposed proximally of the bifurcation, one of said female portions of said second endoluminal stent is disposed in a branched blood vessel, and said first endoluminal stent is adapted to extend from the other one of said female portions into another branched blood vessel.

11. A stent joining means as claimed in claim 5, at least one of said stents comprising a plurality of co-axial hoops, each of said hoops comprising a zig zag pattern around the circumference thereof.

12. A stent joining means as claimed in claim 5 wherein one of said two transversely spaced distal female portions is adapted for connection to said male engaging portion of said first endoluminal stent and said one spaced distal female portion and said first and second endoluminal stents, in combination, extend across a bifurcation in a blood vessel into two respective branched blood vessels.

13. An endoluminal prosthesis system adapted to be assembled within a body lumen, said endoluminal prosthesis system comprising proximal and distal prosthesis segments, a male engaging portion on a selected one of said proximal and distal prosthesis segments, and a female portion on another one of said proximal and distal prosthesis segments, said male engaging portion being configured to be positioned at least partially within said female portion for inter-engagement between the outer surface of said male engaging portion and the inner surface of said female portion to resist longitudinal movement to prevent separation of said proximal and distal prosthesis segments in service, each of said male engaging portion and said female portion comprising a stent and at least one of said proximal and distal prosthesis segments comprising a graft layer attached to said stent, said graft layer being configured to be interposed between said male engaging portion and said female portion to form a substantially fluid-tight seal upon assembly.

14. A system as claimed in claim 13, said graft layer being attached to said scent of at least one of said prosthesis segments by a filament.

15. A system as claimed in claim 13, said stent of at least one of said prosthesis segments having hoops with a common axis positioned along that axis.

16. A system as claimed in claim 15, each of said hoops comprising a plurality of apices alternately pointing in opposite axial directions, oppositely pointed apices in adjoining hoops abutting one another, at least one pair of said abutting apices being joined by a connecting member.

17. A system as claimed in claim 15, each of said hoops comprising wire disposed in a sinuous or zig zag configuration around the circumference of said hoop, the wire of at least one of said hoops being continuous with the wire of an adjacent hoop.

18. A system as claimed in claim 13, wherein an end portion of said stent of at least one of said prosthesis segments extends beyond said graft layer.

19. A system as claimed in claim 13, at least one of said prosthesis segments comprising barbs or hooks adapted to engage a surrounding body lumen and to resist longitudinal movement or slippage of the segment in service.

20. A system as claimed in claim 13, at least one of said prosthesis segments comprising barbs or hooks to resist longitudinal separation of said prosthesis segments in service.

21. A system as claimed in claim 14, at least one of said prosthesis segments comprising a marker, capable of being imaged from outside of a body in which said prosthesis segment is located, said marker being adapted to facilitate proper alignment or positioning of said prosthesis segment.

22. A system as claimed in claim 21, said marker being adapted to facilitate alignment of said prosthesis segment with the other one of the prosthesis segments.

23. A system as claimed in claim 21, wherein the image of said marker differs depending on the rotational orientation of said prosthesis segment so that said rotational orientation can be determined.

24. A system as claimed in claim 13, at least one of said prosthesis segments having a taper to resist longitudinal separation of said prosthesis segments in service.

25. A system as claimed in claim 13, at least one of said prosthesis segments having a flare to engage the body lumen.

26. A system as claimed in claim 13, wherein said graft layer is associated with said female portion, said male engaging portion providing a substantially blood tight seal with said graft layer.

27. A system as claimed in claim 13, said male engaging portion being flared when uncompressed.

28. A system as claimed in claim 13, said male engaging portion being compressible and capable of self re-expansion to engage said female portion.

29. A system as claimed in claim 13, wherein said proximal prosthesis segment defines two distal lumens, one of which is adapted to extend across a bifurcation in a blood vessel such that in use a proximal end of said proximal prosthesis segment is disposed proximally of the bifurcation, and a distal end of said proximal prosthesis segment is disposed in one of the branched blood vessels, the other of said distal lumens comprising said female portion and being disposed intermediate said proximal and distal ends of said proximal prosthesis segment, and said male engaging portion is disposed on said distal prosthesis segment and is adapted to mate with said female portion and to extend into the other of said branched blood vessels.

30. A system as claimed in claim 13, said stents comprising coaxial hoops, each of said hoops defining a zig zag pattern around the circumference thereof.

31. An endoluminal prosthesis system adapted to be assembled within a body lumen, said endoluminal prosthesis system comprising proximal and distal prosthesis segments, a male engaging portion on a selected one of said proximal and distal prosthesis segments, and a female portionon another one of said proximal and distal prosthesis segments, said male engaging portion being configured to be positioned at least partially within said female portion for inter-engagement between the outer surface of said male engaging portion and the inner surface of said female portion to resist longitudinal movement to prevent separation of said proximal and distal prosthesis segments in service, each of said male engaging portion and said female portion comprising a stent, a graft layer being provided adjacent said outer surface of said male engaging portion and adjacent said inner surface of said female portion, said graft layer of said male engaging portion being configured to be in face-to-face contact with said graft layer of said female portion to form a substantially fluid-tight seal upon assembly.

32. An endoluminal prosthesis system adapted to be assembled within a body lumen, said endoluminal prosthesis system comprising proximal and distal prosthesis segments, a male engaging portion on a selected one of said proximal and distal prosthesis segments, and a female portion on another one of said proximal and distal prosthesis segments, said male engaging portion being configured to be positioned at least partially within said female portion for inter-engagement between the outer surface of said male engaging portion and the inner surface of said female portion to resist longitudinal movement to prevent separation of said proximal and distal prosthesis segments in service, each of said male engaging portion and said female portion comprising a stent;

at least one of said proximal and distal segments comprising a portion having a different radiopacity from said at least one of said proximal and distal segments, said portion having a radiographic image that is detectable using a detector outside the body, said radiographic image of said portion differing depending on the rotational orientation of said at least one of said proximal and distal segments so that said rotational orientation in the body lumen can be determined, and said portion having said different radiopacity being configured in a "V" shape.

33. A system for joining endoluminal prosthesis segments in a vessel, said system comprising a male engaging portion on a selected one of said endoluminal prosthesis segments and a female portion on another one of said endoluminal prosthesis segments cooperating with said male engaging portion, each of said male engaging portion and said female portion comprising a stent, said male engaging portion being flared radially outwardly towards an end thereof, said male engaging portion can be entered at least partially into said female portion, and inter-engagement between the outer surface of said male engaging portion and the inner surface of said female portion resists longitudinal movement to prevent separation of said endoluminal prosthesis segments in service.

34. A system as claimed in claim 33, at least one of said prosthesis segments comprising a graft layer attached to said stent by a filament.

35. A system as claimed in claim 33, said stent of at least one of said male engaging portion and said female portion defining hoops having a common axis and positioned along that axis.

36. A system as claimed in claim 35, said hoops having a plurality of apices alternatingly pointing in opposite axial directions, oppositely pointed apices of adjoining hoops abutting one another, said abutting apices being joined by a connecting member.

37. A system as claimed in claim 35, the configuration of each of said hoops including:

a plurality of apices disposed about the circumference of said hoop and alternatingly pointing in opposite axial directions; and

a member which extends, as a single continuous member, from an apex pointed in a first axial direction to the apex of an adjacent hoop pointed in the opposite axial direction.

38. A system as claimed in claim 33, at least one of said prosthesis segments comprising a graft layer, wherein an end portion of said stent of said prosthesis segment extends beyond said graft layer.

39. A system as claimed in claim 33, at least one of said prosthesis segments comprising barbs or hooks adapted to engage a surrounding body lumen and to resist longitudinal movement or slippage of the prosthesis segment in service.

40. A system as claimed in claim 33, at least one of said prosthesis segments comprising barbs or hooks to resist longitudinal separation of said prosthesis segments in service.

41. A system as claimed in claim 33, at least one of said prosthesis segments comprising a radiopaque marker, said radiopaque marker being adapted to facilitate proper alignment or positioning of said prosthesis segment.

42. A system as claimed in claim 41, said radiopaque marker being adapted to facilitate alignment of said prosthesis segment with the other one of said prosthesis segments.

43. A system as claimed in claim 41, wherein the radiographic image of said radiopaque marker differs depending on the rotational orientation of said prosthesis segment so that said rotational orientation can be determined.

44. A system as claimed in claim 33, at least one of said prosthesis segments having a taper to resist longitudinal separation of said prosthesis segments in service.

45. A system as claimed in claim 33, at least one of said prosthesis segments having a flare to engage the body lumen.

46. A system as claimed in claim 33, wherein a graft layer is associated with said female portion, said male engaging portion providing a substantially blood tight seal with said graft layer.

47. A system as claimed in claim 33, said male engaging portion being flared when uncompressed.

48. A system as claimed in claim 33, said male engaging portion being compressible and capable of self re-expansion to engage said female portion.

49. A system as claimed in claim 33, wherein a proximal prosthesis segment defines two distal lumens, one of which is adapted to extend across a bifurcation in a blood vessel such that in use a proximal end of said proximal prosthesis segment is disposed proximally of the bifurcation, and a distal end of said proximal prosthesis segment is disposed in one of the branched blood vessels, the other of said distal lumens comprising said female portion and being disposed intermediate said proximal and distal ends of said proximal prosthesis segment, and said male engaging portion is disposed on a distal prosthesis segment and is adapted to mate with said female portion and to extend into the other of said branched blood vessels.

50. A system as claimed in claim 33, said stent of at least one of said male engaging portion and said female portion comprising a plurality of hoops, each defining a zig zag pattern about the circumference thereof.

51. A system for joining endoluminal prosthesis segments in a vessel, said system comprising a male engaging portion on a selected one of said endoluminal prosthesis segments and a female portion on another one of said endoluminal prosthesis segments cooperating with said male engaging portion, each of said male engaging portion and said female portion comprising a stent, said female portion being tapered radially inwardly towards an end thereof, said male engaging portion can be entered at least partially into said female portion, and inter-engagement between the outer surface of said male engaging portion and the inner surface of said female portion resists longitudinal movement to prevent separation of said endoluminal prosthesis segments in service.

52. An endoluminal prosthesis system adapted to be assembled within a body lumen to provide a continuous lumen, said endoluminal prosthesis system comprising:

proximal and distal prosthesis segments, said proximal and distal prosthesis segments each comprising a graft layer;

a male engaging portion on a selected one of said proximal and distal prosthesis segments and a female portion on another one of said proximal and distal prosthesis segments, each of said male engaging portion and said female portion comprising a stent, said male engaging portion being configured to be positioned at least partially within said female portion for contact between the outer surface of said male engaging portion and the inner surface of said female portion, said graft layers of said proximal and distal prosthesis segments together defining a substantially continuous lumen upon assembly of said proximal and distal prosthesis segments, and said graft layer of at least one of said proximal and distal prosthesis segments is configured to be interposed between said male engaging portion and said female portion to form a substantially fluid-tight seal upon assembly.

53. A system as claimed in claim 52, said graft layer of each of said proximal and distal prosthesis segments being attached to a respective one of said stents by a filament.

54. A system as claimed in claim 52, said stent of at least one of said male engaging portion and said female portion comprising a plurality of hoops having a common axis and positioned along that axis.

55. A system as claimed in claim 54, wherein each of said hoops comprises a zig zag or sinuous configuration extending around the circumference of said hoop.

56. A system as claimed in claim 54, each of said hoops comprising a plurality of apices alternately pointing in opposite axial directions, oppositely pointed apices in adjoining hoops abutting one another, at least one pair of said abutting apices being joined by a connecting member.

57. A system as claimed in claim 54, each of said hoops comprising wire disposed in a sinuous or zig zag configuration around the circumference of said hoop, the wire of at least one of said hoops being continuous with the wire of an adjacent hoop.

58. A system as claimed in claim 52, wherein an end portion of at least one of said stents extends beyond a respective one of said graft layers.

59. A system as claimed in claim 52, at least one of said prosthesis segments comprising barbs or hooks adapted to engage a surrounding body lumen and to resist longitudinal movement or slippage of the prosthesis segment in service.

60. A system as claimed in claim 52, at least one of said prosthesis segments comprising barbs or hooks to resist longitudinal separation of said prosthesis segments in service.

61. A system as claimed in claim 52, at least one of said prosthesis segments comprising a radiopaque marker, said radiopaque marker being adapted to facilitate proper alignment or positioning of said prosthesis segment.

62. A system as claimed in claim 61, said radiopaque marker being adapted to facilitate alignment of said prosthesis segment with the other one of said prosthesis segments.

63. A system as claimed in claim 61, wherein the radiographic image of said radiopaque marker differs depending on the rotational orientation of said prosthesis segment so that said rotational orientation can be determined.

64. A system as claimed in claim 52, at least one of said prosthesis segments having a taper to resist longitudinal separation of said prosthesis segments in service.

65. A system as claimed in claim 52, at least one of said prosthesis segments having a flare to engage the body lumen.

66. A system as claimed in claim 52, said male engaging portion providing a substantially blood tight seal with said graft layer associated with said female portion.

67. A system as claimed in claim 52, said male engaging portion being flared when uncompressed.

68. A system as claimed in claim 52, said male engaging portion being compressible and capable of self re-expansion to engage said female portion.

69. A system as claimed in claim 53, wherein said proximal prosthesis segment defines two distal lumens, one of which is adapted to extend across a bifurcation in a blood vessel such that in use a proximal end of said proximal prosthesis segment is disposed proximally of the bifurcation, and a distal end of said proximal prosthesis segment is disposed in one of the branched blood vessels, the other of said distal lumens comprising said female portion and being disposed intermediate said proximal and distal ends of said proximal prosthesis segment, and said male engaging portion is disposed on said distal prosthesis segment and is adapted to mate with said female portion and to extend into the other of said branched blood vessels.

70. A system as claimed in claim 52, said stent of at least one said male engaging portion and said female portion comprising a plurality of co-axial hoops each defining a zig zag pattern.

71. An endoluminal prosthesis system adapted to be assembled within a body lumen to provide a continuous lumen, said endoluminal prosthesis system comprising:

proximal and distal prosthesis segments, said proximal and distal prosthesis segments each comprising a graft layer;

a male engaging portion on a selected one of said proximal and distal prosthesis segments and a female portion on another one of said proximal and distal prosthesis segments, each of said male engaging portion and said female portion comprising a stent, said male engaging portion being configured to be positioned at least partially within said female portion for contact between the outer surface of said male engaging portion and the inner surface of said female portion, a graft layer portion being provided adjacent said outer surface of said male engaging portion and a graft layer portion being provided adjacent said inner surface of said female portion, said graft layer portion of said male engaging portion being configured to be in face-to-face contact with said graft layer portion of said female portion to form a substantially fluid-tight seal upon assembly and to define a substantially continuous lumen upon assembly of said proximal and distal prosthesis segments.

72. A stent joining means for joining a first endoluminal stent to a second endoluminal stent to define a continuous lumen through the first and second endoluminal stents, said stent joining means comprising:

two transversely spaced female portions on said first endoluminal stent, each of said female portions having an inner surface;

a male engaging portion on said second endoluminal stent which has an outer surface and can be compressed radially inwardly, the male engaging portion being configured to be entered into one of the female portions in a radially compressed state and thereafter expanded in the female portion such that the outer surface of the male engaging portion and the inner surface of the female portion are inter-engaged to resist longitudinal movement to prevent separation of the first and second endoluminal stents in service; and

a graft layer attached to at least one of said first and second endoluminal stents, said graft layer being configured to be interposed between said male engaging portion and said female portion to form a substantially fluid-tight seal upon assembly.

73. A stent joining means as claimed in claim 72, said graft layer being attached to at least one of said stents by a filament.

74. A stent joining means as claimed in claim 72, at least one of said stents having hoops with a common axis, said hoops being positioned along said axis.

75. A stent joining means as claimed in claim 74, each of said hoops comprising a plurality of apices pointing alternately in opposite axial directions, oppositely pointed apices of adjoining hoops abutting one another, at least some of said abutting apices being joined by a connecting member.

76. A stent joining means as claimed in claim 74, each of said hoops comprising wire disposed in a sinuous or zig zag configuration around the circumference of said hoop, the wire of at least one of said hoops being continuous with the wire of an adjacent hoop.

77. A stent joining means as claimed in claim 72, wherein an end portion of said at least one stent to which said graft layer is attached extends beyond said graft layer.

78. A stent joining means as claimed in claim 72, at least one of said stents comprising barbs or hooks adapted to engage a surrounding body lumen and to resist longitudinal movement or slippage of said stent in service.

79. A stent joining means as claimed in claim 72, at least one of said stents comprising barbs or hooks to resist longitudinal separation of said stents in service.

80. A stent joining means as claimed in claim 72, at least one of said stents comprising at least one marker, imageable from outside a body in which said stent is located, said marker being adapted to facilitate proper alignment or positioning of said stent.

81. A stent joining means as claimed in claim 80, wherein the image of said marker differs depending on the rotational orientation of said stent so that said rotational orientation can be determined.

82. A stent joining means as claimed in claim 80, wherein said marker is adapted to facilitate alignment of said stent with the other of said stents.