Stent delivery apparatus and method

• US 20040215312A1
• Filed: 03/03/2004
• Published: 10/28/2004
• Est. Priority Date: 12/03/2001
• Status: Active Grant

• Current Assignee: JW Medical Systems Ltd
• Original Assignee: XTENT, Inc.
• Inventors: Andreas, Bernard
• Granted Patent: US 7,351,255 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• 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 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2002/826 more than one stent being applied sequentially
• CPC Class Codes: A61F 2002/828 Means for connecting a plurality of stents allowing flexibility of the whole structure
• CPC Class Codes: A61F 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/9155 Adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91558 connected peak to peak

Abstract

Apparatus and methods for stent delivery provide for dilatation at a treatment site as well as stent delivery, using the same stent delivery apparatus. Apparatus generally include a catheter having at least one expandable member, at least one stent positionable thereon, and a sheath disposed over the expandable member and the stent. Some embodiments include separate expandable members for dilatation of a lesion and for stent expansion, while other embodiments use the same expandable member for both. In some embodiments a stent includes multiple separable stent segments. In various embodiments, self-expanding stents may be used. Methods involve positioning a stent delivery device at a treatment site, expanding an expandable member to dilate at least a portion of a lesion at the treatment site, and expanding (or allowing to expand) a stent at the treatment site.

Claims

1. A stent delivery device for delivering at least one stent to a treatment site, the device comprising:

a catheter shaft having a proximal end and a distal end;

at least one stent positionable on the catheter shaft;

a stent deployment mechanism for deploying at least a portion of the stent at the treatment site, the deployment mechanism allowing a length of the deployed portion of the stent to be selected; and

a dilatation member for dilating at least a portion of a lesion at the treatment site independently of deploying the at least one stent.

2. A device as in claim 1, wherein the length of the deployed portion of the stent is selected in situ.

3. A device as in claim 1, wherein a length of the dilatation member to be expanded to dilate the lesion is selected in situ.

4. A device as in claim 1, wherein the stent deployment mechanism comprises:

a stent expansion member coupled with the catheter shaft near the distal end; and

at least one axially movable sheath disposed over at least part of the stent expansion member and stent thereon.

5. A device as in claim 4, wherein the stent expansion member also acts as the dilatation member.

6. A device as in claim 4, wherein the dilatation member is coupled with the sheath.

7. A device as in claim 4, wherein the dilatation member is coupled with an inner shaft slidably disposed within the catheter shaft.

8. A device as in claim 4, wherein the stent comprises a plurality of separable stent segments.

9. A device as in claim 8, wherein the separable stent segments are axially movable along the stent expansion member.

10. A device as in claim 9, further comprising a pusher member for advancing the stent segments axially along the stent expansion member.

11. A device as in claim 8, wherein the sheath is configured to constrain expansion of a first portion of the stent expansion member and a first plurality of the stent segments while allowing expansion of a second portion of the stent expansion member and a second plurality of the stent segments.

12. A device as in claim 11, wherein the sheath further comprises at least one separation device for separating the first plurality of stent segments from the second plurality, thus allowing for expansion of a stent segment without interfering with adjacent stent segments.

13. A device as in claim 4, wherein the stent expansion member and the dilatation member are independently expandable.

14. A device as in claim 13, further including at least one inflation lumen for expanding the dilatation member.

15. A device as in claim 14, wherein the inflation lumen comprises a tubular member disposed concentrically over the sheath.

16. A device as in claim 14, wherein the inflation lumen comprises a tubular member coupled with and extending along the outer surface of the sheath.

17. A device as in claim 14, wherein the inflation lumen is disposed within a wall of the sheath.

18. A stent delivery device for delivering at least one stent to a treatment site, the device comprising:

a catheter shaft having a proximal end and a distal end;

an expandable member coupled with the catheter shaft near the distal end;

at least one stent slidably positionable on the expandable member; and

at least one axially movable sheath disposed over at least part of the expandable member and stent thereon, wherein the sheath is axially movable relative to the catheter body to expose at least a portion of the expandable member without exposing the stent, and wherein the sheath is also movable to expose at least a portion of the stent to allow it to expand.

19. A device as in claim 18, wherein the exposed portion of the expandable member is expanded to dilate a lesion at the treatment site, and wherein a length of the exposed portion of is selected in situ.

20. A device as in claim 18, wherein a length of the exposed portion of the stent is selected in situ.

21. A device as in claim 18, wherein the stent is self-expanding.

22. A device as in claim 18, further including a pusher member for advancing the stent along the expandable member.

23. A device as in claim 18, wherein the stent comprises a plurality of separable, self-expanding stent segments.

24. A device as in claim 23, wherein the sheath is configured to constrain expansion of a first plurality of the stent segments while allowing expansion of a second plurality of the stent segments.

25. A device as in claim 24, wherein the sheath further comprises at least one separation device for separating the first plurality of stent segments from the second plurality, thus allowing for expansion of a stent segment without interfering with adjacent stent segments.

26. A device as in claim 23, wherein the stent segments comprise a thermal shape memory material, and wherein the expandable member is configured to accept one or more heated or cooled fluids to change a temperature of the stent segments.

27. A stent delivery device for treating a target site in a vessel, the device comprising:

a catheter shaft having a proximal end and a distal end;

a first stent carried on the catheter shaft and being deployable therefrom;

a second stent carried on the catheter shaft and being deployable therefrom independently of the first stent; and

a dilatation member for dilating the target site independently of deploying the first and second stents.

28. A stent delivery device for delivering at least one stent to a treatment site, the device comprising:

a catheter shaft having a proximal end and a distal end;

a stent expansion member coupled with the catheter shaft near the distal end;

at least one stent positionable on the stent expansion member;

at least one axially movable sheath disposed over at least part of the stent expansion member and stent thereon; and

a dilatation member coupled with the sheath for dilating one or more lesions at the treatment site.

29. A device as in claim 28, wherein the stent comprises a plurality of separable stent segments.

30. A device as in claim 29, wherein the separable stent segments are axially movable along the stent expansion member.

31. A device as in claim 30, further comprising a pusher member for advancing the stent segments axially along the stent expansion member.

32. A device as in claim 29, wherein the sheath is configured to constrain expansion of a first portion of the stent expansion member and a first plurality of the stent segments while allowing expansion of a second portion of the stent expansion member and a second plurality of the stent segments.

33. A device as in claim 32, wherein the sheath further comprises at least one separation device for separating the first plurality of stent segments from the second plurality, thus allowing for expansion of a stent segment by the stent expansion member without interfering with adjacent stent segments.

34. A device as in claim 28, wherein the stent expansion member and the dilatation member are independently expandable.

35. A device as in claim 34, further including at least one inflation lumen for expanding the dilatation member.

36. A device as in claim 35, wherein the inflation lumen comprises a tubular member disposed concentrically over the sheath.

37. A device as in claim 35, wherein the inflation lumen comprises a tubular member coupled with and extending along the outer surface of the sheath.

38. A device as in claim 35, wherein the inflation lumen is disposed within a wall of the sheath.

39. A stent delivery device for delivering at least one stent to a treatment site, the device comprising:

a catheter shaft having a proximal end and a distal end;

at least one stent positionable on the catheter shaft;

at least one axially movable sheath disposed over the catheter shaft and stent;

an inner shaft slidably disposed within the catheter shaft; and

a dilatation member coupled with a distal end of the inner shaft for dilating one or more lesions at the treatment site.

40. A device as in claim 39, further comprising a stent expansion member coupled with the catheter shaft near the distal end, the stent being positionable on the expansion member.

41. A device as in claim 40, wherein the dilatation member and the stent expansion member are separately expandable.

42. A device as in claim 39, wherein the stent comprises a plurality of separable stent segments.

43. A device as in claim 42, wherein the separable stent segments are axially movable relative to the catheter shaft.

44. A device as in claim 43, further including a pusher member for advancing the stent segments along the catheter shaft.

45. A device as in claim 42, wherein the sheath is configured to constrain expansion of a first plurality of the stent segments while allowing expansion of a second plurality of the stent segments.

46. A device as in claim 45, wherein the sheath further comprises at least one separation device for separating the first plurality of stent segments from the second plurality, thus allowing for expansion of a stent segment without interfering with adjacent stent segments.

47. A device as in claim 39, wherein the inner shaft comprises a tubular catheter shaft.

48. A device as in claim 39, wherein the inner shaft comprises a guidewire.

49. A device as in claim 39, wherein the inner shaft is slidable to expose at least part of the dilatation member out of the distal end of the catheter shaft, and wherein the inner shaft is slidable to retract the dilatation member to a position at least partially within the catheter shaft.

50. A device as in claim 49, wherein the dilatation member is expandable while only a portion is exposed out of the distal end of the catheter shaft.

51. A device as in claim 50, wherein the dilatation member is positionable relative to the catheter shaft to adjust a length of the exposed portion of the dilatation member to dilate a desired length of the lesion at the treatment site.

52. A device as in claim 39, further including at least one inflation lumen for expanding the dilatation member.

53. A device as in claim 52, wherein the inflation lumen comprises a tubular member disposed concentrically over the inner shaft.

54. A device as in claim 52, wherein the inflation lumen comprises an internal lumen disposed within the inner shaft.

55. A method for delivering at least one stent to a treatment site, the method comprising:

positioning a distal portion of a stent delivery catheter device at the treatment site, the stent delivery catheter carrying at least one stent;

expanding at least a portion of an expandable member on the catheter device to dilate at least a portion of a lesion at the treatment site;

selecting a deployable portion of the stent having a selected length; and

expanding the deployable portion of the stent at the treatment site, an undeployed portion of the stent remaining in the delivery catheter.

56. A method as in claim 55, further comprising positioning the deployable portion of the stent over the expandable member.

57. A method as in claim 55, wherein expanding the deployable portion of the stent comprises expanding the expandable member.

58. A method as in claim 55, further comprising retracting a sheath disposed over the expandable member to expose at least the portion of the expandable member before dilating the lesion.

59. A method as in claim 58, wherein retracting the sheath also retracts the at least one stent relative to the expandable member.

60. A method as in claim 55, wherein the at least one stent comprises a plurality of stent segments, and wherein positioning at least the portion of the at least one stent over the expandable member comprises positioning at least one stent segment over the expandable member.

61. A method as in claim 60, wherein positioning the at least one stent segment over the expandable member comprises:

allowing the expandable member to return to an unexpanded form; and

retracting the unexpanded expandable member to a position within the at least one stent segment.

62. A method as in claim 61, further comprising retracting a sheath disposed over the expandable member and the plurality of stent segments to expose at least the portion of the expandable member and stent segments thereon.

63. A method for delivering at least one stent segment to a treatment site, the method comprising:

positioning a distal portion of a stent delivery catheter device at the treatment site, the stent delivery catheter carrying at least one stent;

expanding at least a portion of an expandable member on the catheter device to dilate at least a portion of a lesion at the treatment site; and

retracting a sheath on the catheter device to expose at least a portion of the at least one stent from within the sheath, the portion self-expanding at the treatment site.

64. A method as in claim 63, wherein the at least one stent comprises a plurality of stent segments, and wherein retracting the sheath exposes at least one of the stent segments to self-expand at the treatment site.

65. A method as in claim 64, further comprising, after retracting the sheath:

positioning the expandable member within the at least one self-expanded stent segment; and

expanding at least a portion of the expandable member to further expand the stent segment.

66. A method as in claim 63, further comprising exposing the portion of the expandable member outside the sheath before the expanding step.

67. A method as in claim 66, further comprising retracting the portion of the expandable member to a position within the sheath after the expanding step.

68. A method as in claim 63, further comprising passing a fluid through the expandable member while the stent segments are disposed thereon, wherein the stent segments comprise a thermal shape memory material, and wherein passing the fluid changes the temperature of the stent segments.

69. A method as in claim 68, wherein the passed fluid is heated to a temperature higher than body temperature.

70. A method as in claim 68, wherein the passed fluid is cooled to a temperature lower than body temperature.

71. A method as in claim 68, wherein the portion of the expandable member is expanded using the fluid.

72. A method for delivering at least one stent to a treatment site, the method comprising:

positioning a distal portion of a stent delivery catheter device at the treatment site, the stent delivery catheter carrying at least one stent;

expanding at least a portion of a dilatation member of the catheter device to dilate at least a portion of a lesion at the treatment site; and

expanding at least a portion of a stent expansion member of the catheter device to deploy at least a portion of the at least one stent at the treatment site.

73. A method as in claim 72, further comprising selecting a deployable portion of the stent, wherein the deployable portion is expanded by the stent expansion member while an undeployed portion of the stent remains unexpanded in the stent delivery catheter.

74. A method as in claim 72, wherein the at least one stent comprises a plurality of stent segments, and wherein deploying at least the portion comprises deploying at least one of the stent segments.

75. A method as in claim 72, wherein the dilatation member is disposed on an outer surface of a sheath slidably disposed over the stent and the stent expansion member.

76. A method as in claim 75, further comprising retracting the sheath to expose at least the portion of the stent expansion member and at least one stent.

77. A method as in claim 72, further comprising sliding an inner shaft of the catheter device distally relative to the stent expansion member to expose at least the portion of the dilatation member is disposed on the inner shaft.

78. A method as in claim 77, further comprising sliding the catheter body distally over the inner shaft to position the stent expansion member at the treatment site.

79. A method as in claim 77, further comprising re-expanding the dilatation member at the treatment site after the stent is deployed.