Stent delivery system having stent securement apparatus

• US 20040133263A1
• Filed: 12/16/2003
• Published: 07/08/2004
• Est. Priority Date: 08/23/1996
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Blaeser, David J., Mattison, Richard C., Dusbabek, Andrew J., Euteneuer, Charles L., Larson, Christopher R., Di Caprio, Fernando, Nordin, Stanley A., Ellis, Louis G., Lorentzen Cornelius, Linda R., Willard, Martin R., Brown, Terry V., Mertens, Steven P.
• Granted Patent: US 7,670,364 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/9583 Means for holding the stent on the balloon, e.g. using protrusions, adhesives or an outer sleeve
• CPC Class Codes: A61F 2002/9586 the means being inside the balloon
• CPC Class Codes: A61M 2025/1013 with concentrically mounted balloons, e.g. being independently inflatable
• CPC Class Codes: A61M 2025/1063 having only one lumen used for guide wire and inflation, e.g. to minimise the diameter
• CPC Class Codes: A61M 2025/1079 having radio-opaque markers in the region of the balloon
• CPC Class Codes: A61M 2025/1081 having sheaths or the like for covering the balloon but not forming a permanent part of the balloon, e.g. retractable, dissolvable or tearable sheaths
• CPC Class Codes: A61M 2025/1093 having particular tip characteristics
• CPC Class Codes: A61M 25/1011 Multiple balloon catheters
• CPC Class Codes: A61M 25/1018 Balloon inflating or inflation-control devices
• CPC Class Codes: A61M 25/10182 Injector syringes
• CPC Class Codes: A61M 25/10184 Means for controlling or monitoring inflation or deflation
• CPC Class Codes: A61M 25/10186 One-way valves
• CPC Class Codes: A61M 25/104 used for angioplasty

Abstract

A system/assembly for delivery and deployment of an inflation expandable stent within a vessel, comprising a catheter having proximal and distal ends; a stent, inflation expandable from a delivery diameter to a deployment diameter, such that the delivery diameter is reduced from the deployment diameter for conforming the stent to the catheter, such that the stent, in its delivery diameter, is coaxially mounted on the catheter near the catheter distal end; an expandable inflation means coaxially mounted on the catheter axially within the stent, for expansion of the stent from the delivery diameter to the deployment diameter upon application of fluid deployment pressure to the inflation means; and a securement component coaxially mounted on the catheter, axially within the expandable inflation means, the securement component designed and adapted to provide a securement pressure to the stent in the delivery diameter to maintain the stent in position on the catheter during delivery to the deployment site.

Claims

1. A system/assembly for delivery and deployment of an inflation expandable stent within a vessel, comprising:

a catheter having proximal and distal ends;

a stent, inflation expandable from a delivery diameter to a deployment diameter, such that the delivery diameter is reduced from the deployment diameter for conforming the stent to the catheter, such that the stent, in its delivery diameter, is coaxially mounted on the catheter near the catheter distal end;

an expandable inflation means coaxially mounted on the catheter axially within the stent, for expansion of the stent from the delivery diameter to the deployment diameter upon application of fluid deployment pressure to the inflation means; and

a securement component coaxially mounted on the catheter, axially within the expandable inflation means, the securement component designed and adapted to provide a securement pressure to the stent in the delivery diameter to maintain the stent in position on the catheter during delivery to the deployment site.

2. The system of claim 1, the catheter having a shaft and the expandable inflatable means associated therewith at a distal part of the shaft and including mounting and retaining means for receiving the stent on the expandable means for radial expansion of the stent, the mounting and retaining means being associated with the inflatable means and being constructed and arranged for selectively providing an enlarged mounting body for receiving the stent.

3. The system of claim 2 wherein the mounting body is inside the inflatable means.

4. The system of claim 2 wherein the mounting body is outside the inflatable means.

5. The system of claim 2, the inflatable means being a balloon, wherein the mounting body is carried by the catheter and is axially movable between the stent mounting position associated with the balloon and a position removed from the stent mounting position.

6. The system of claim 1, the catheter having a shaft, the expandable inflatable means being associated therewith at a distal part of the shaft and including mounting and retaining means for receiving a stent on the expandable inflatable means and for radial expansion of the stent upon inflation of the inflatable means, the mounting and retaining means including at least one mounting body carried on and surrounding the shaft inside the inflatable means whereby the diameter of the shaft and inflatable portion may be increased at the distal part of the shaft for facilitating the mounting and retaining of the stent.

7. The delivery system of claim 6 wherein the mounting body is axially movable with respect to the inside shaft, and including means for moving the mounting body.

8. The stent delivery system of claim 7 wherein the mounting body is of a material which resiliently deforms under radial pressure.

9. The stent delivery system of claim 8 wherein the material comprises HDPE or silicone.

10. The stent delivery system of claim 7 wherein the mounting body configuration includes at least one separation whereby the flexibility of the body and catheter is increased.

11. The stent delivery system of claim 10 wherein the separation is in the form of a spiral.

12. The stent delivery system of claim 7 wherein the mounting body is positionable to receive a stent and a stent is crimped to the mounting and retaining means over the balloon for delivery.

13. The stent delivery system of claim 6 including a stop positioned at the distal end portion of the inflatable means and carried by the shaft inside the inflatable means.

14. The stent delivery system of claim 6 including at least one marker band.

15. The stent delivery system of claim 6 wherein the inflatable means comprises a balloon.

16. The stent delivery system of claim 6 including a stop positioned at the distal end of the catheter and carried by the shaft inside the inflatable means.

17. The stent delivery system of claim 6 wherein the mounting body is in a fixed position and is adapted and arranged to enlarge in diameter to receive a stent.

18. The stent delivery system of claim 17 wherein the mounting body is a second inflatable means inside the first inflatable means, the inner one being shaped to have wide end portions and a narrow center portion.

19. The stent delivery system of claim 17 wherein the mounting body is a coil-like structure adapted and arranged to be compressed and the proximal portion of the inside shaft is connected thereto for compressing the structure to enlarge its diameter.

20. The system of claim 17 wherein the mounting body is a sleeve including radial accordion like pleats extending over at least a portion of its length, the distal end being secured to the inside shaft and a means for compressing the body from its proximal end and attached thereto.

21. The system of claim 20 wherein the pleats of certain portions of the body are spaced differently to provide regions of different enlargement.

22. The stent delivery system of claim 19 wherein the coil is coated with a polymer.

24. The stent delivery system of claim 7 wherein the mounting body is a slidably carried coil.

25. The system of claim 1, the inflation means being a balloon, and further including an elastomeric sheath carried over the balloon, the sheath being constructed and arranged for axial movement and positioning between a stent mounting position over the balloon and a position removed from the stent mounting position.

41. The assembly according to claim 1, the catheter having an inner shaft, the inflatable means being an expandable balloon coaxially mounted on the catheter axially;

and the securement component comprising a tube component coaxially mounted on the catheter axially within the expandable balloon, the tube component having a plurality of ribs.

42. The assembly according to claim 41, further comprising a stent, inflation expandable from a delivery diameter to a deployment diameter, such that the delivery diameter is reduced from the deployment diameter for conforming the stent to the catheter, such that the stent, in its delivery diameter, is coaxially mounted on the catheter near the catheter distal end, the expandable balloon being capable of expansion of the stent from the delivery diameter to the deployment diameter upon application of fluid deployment pressure to the balloon.

43. The assembly according to claim 42, the catheter comprising an inner shaft and an outer shaft, wherein the tube component is a thermoplastic corrugated tube adhered to the inner shaft and is formed from a low modulus polymer.

44. The assembly according to claim 43, the tube component being formed from a material chosen from the group consisting of polypropylene, low density polyethylene (LDPE), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), nylon, polyester, polyethylene terephthalate (“

PET”

), Surlyn™

, Pebax and urethane

45. The assembly according to claim 43, wherein the diameter of the tube component is approximately equal to the delivery diameter of the stent.

46. The assembly according to claim 45, wherein the tube component is essentially equal in length to the stent and wherein the stent is positioned on the assembly essentially coextensive with the tube component.

47. The assembly according to claim 42, wherein the tube component is comprised of more than one corrugated tube.

48. The assembly according to claim 46, further comprising marker bands fixed to the inner shaft beneath the tube component.

49. The assembly according to claim 42, wherein the tube component is inflatable, such that when the tube component is inflated it applies radial pressure on the expandable balloon, when the stent is in its delivery diameter.

50. The assembly according to claim 42, further comprising at least one sleeve having first and second ends, the first end being attached to the catheter and the second end covering a portion of the stent;

when the stent is in its delivery diameter.

51. The assembly according to claim 50, comprising two sleeves, one covering each end of the stent, when the stent is in its delivery diameter.

52. The assembly according to claim 42, wherein the tube component is slidable along the inner shaft and is attached to a retracting means, such that after the stent has been deployed, the user may slide the tube component proximally along the inner shaft.

53. A method for delivering and deploying a stent using an assembly according to claim 41, comprising:

providing a catheter having proximal and distal ends, with an expandable balloon coaxially mounted on the catheter, and a tube component having a plurality of ribs coaxially mounted on the catheter, axially within the expandable balloon, so that the balloon is in an unexpanded condition;

providing a stent which is expandable from a delivery diameter to a deployment diameter;

mounting the stent, in a diameter greater than the delivery diameter, on the balloon;

contracting the stent to the delivery diameter to conform to an overall profile of the catheter, the tube component and the balloon;

delivering the assembly to a deployment site; and

inflating the balloon to expand the stent to its deployment diameter.

54. The method according to claim 53, wherein the tube component is a corrugate tubing adhered to the catheter formed of a low modulus polymer and having a diameter of approximately that of the delivery diameter.

55. The assembly of claim 1, the inflatable means comprising an expandable balloon, further comprising an annular collar coaxially located at the catheter distal end portion, the expandable balloon coaxially mounted over the collar at the catheter distal end portion, the balloon being expandable from a contracted to an expanded state, the stent coaxially mounted on the balloon, the reduced condition conforming the stent to the balloon, collar and catheter, the stent having at least an end portion overlying the balloon, the system further comprising a cup coaxially mounted on the catheter distal end portion, the cup having a first end portion restraining the stent end portion and the cup and collar cooperatively constructed and arranged to retain the stent end portion on the catheter in the stent reduced condition when the balloon-is in the contracted state, the balloon and catheter cooperatively constructed and arranged to cause expansion of the balloon from the contracted to the expanded state and to release the stent end portion from the cup end portion.

56. The assembly according to claim 55, wherein the cup is axially spaced from the collar.

57. The assembly according to claim 55, wherein the cup has a second end portion fixed to the catheter.

58. The assembly according to claim 55, wherein the cup first end portion overlies the stent end portion.

59. The assembly according to claim 55, wherein the cup is elastomeric.

60. The assembly according to claim 55, wherein the cup is rigid.

61. The assembly according to claim 57, wherein the second end portion is fixed with adhesive.

62. The assembly according to claim 55, wherein the collar is formed as a single member with the catheter.

63. The assembly according to claim 55,;

wherein the stent end portion is a distal end portion and wherein the cup and collar cooperate to retain the stent at the stent distal end portion.

64. The assembly according to claim 55, wherein the collar is axially positioned exterior to the stent at a stent end portion opposite the stent end portion retained by the cup.

65. The assembly according to claim 64 wherein the collar is formed as a single member with the catheter.

66. The assembly according to claim 55, wherein the collar is a mounting ring axially positioned between stent end portions.

67. The assembly according to claim 66, wherein the mounting ring is formed as a single member with the catheter.

68. The assembly according to claim 66, wherein at least a portion of the mounting ring is contained by the cup.

69. The assembly according to claim 55, wherein the collar is a cylinder under the stent.

70. The assembly according to claim 69, wherein at least a portion of the cylinder is contained by the cup.

71. The assembly according to claim 69, wherein the cylinder is formed as a single member with the catheter.

72. The assembly according to claim 55, wherein a second collar is a mounting ring axially positioned between stent end portions.

73. The assembly according to claim 55, wherein a second collar is axially positioned immediately exterior to the stent at a stent end portion opposite the stent end portion retained by the cup.

74. The assembly according to claim 55, wherein the cup and the collar are each cylindrical.

75. The assembly according to claim 55, wherein the cup has a second end portion with axially running regions of weakness.

76. The assembly according to claim 55, and further including a second cup coaxially mounted on the catheter at the catheter distal end, the second cup having a first end portion overlying a stent second end portion;

the cups and the collar cooperatively constructed and arranged to retain the respective stent end portions on the catheter in the stent reduced condition when the balloon is in the contracted state, the balloon and catheter cooperatively constructed and arranged to cause expansion of the balloon from the contracted to the expanded state to cause release of the stent end portions from the cup end portions.

77. The assembly according to claim 76, wherein the cups are elastomeric.

78. The assembly according to claim 76, wherein the cups are rigid.

79. The assembly according to claim 76, wherein the collar is formed as a single member with the catheter.

80. The assembly according to claim 76, wherein the collar is axially positioned immediately exterior to the stent at a stent end portion opposite the stent end portion retained by the cup.

81. The assembly according to claim 80, wherein the collar is shaped as a single member with the catheter.

82. The assembly according to claim 76, wherein the collar is a mounting ring axially positioned between stent end portions.

83. The assembly according to claim 82, wherein the mounting ring is shaped as a single member with the catheter.

84. The assembly according to claim 82, wherein at least a portion of the mounting ring is contained by a cup.

85. The assembly according to claim 76, wherein the collar is a cylinder coextensive with the length of the stent.

86. The assembly according to claim 85, wherein the cylinder is formed as a single member with the catheter.

87. The assembly according to claim 85, wherein at least a portion of the cylinder is contained by a cup.

88. The assembly according to claim 87, wherein each cup contains at least a portion of the cylinder.

89. The assembly according to claim 76, wherein a second collar is a mounting ring axially positioned between stent end portions.

90. The assembly according to claim 76, wherein a second collar is axially positioned immediately exterior to the stent at a stent end portion opposite the stent end portion retained by the cup.

91. The assembly according to claim 76, and further comprising fixing means for holding the collar at a specific location on the catheter, wherein the fixing means is adhesive.

92. A method for delivering and deploying a stent using the assembly of claim 55, comprising:

providing a catheter having proximal and distal ends, with a collar coaxially mounted at the catheter distal end, and a fluid expandable balloon coaxially mounted over the collar on the catheter distal end,

providing a stent being expandable from a reduced to an enlarged condition;

mounting the stent in the reduced condition coaxially on the balloon, so that an end portion of the stent overlies the balloon;

providing a cup having first and second end portions, the cup being in an expanded form, and also having a retracted form;

mounting the expanded cup coaxially on the catheter distal end, so that the cup first end portion overlies the stent end portion;

contracting the cup about the catheter and the stent end portion to fix the stent to the catheter, the cup and collar cooperating to retain the stent in the reduced condition,

delivering the assembly to a deployment site; and

inflating the balloon to release the stent from the cup.

93. The assembly according to claim 1, the securement component comprising a mounting body carried by the catheter at the distal end portion, the inflatable means comprising an expandable balloon coaxially mounted over the catheter distal end and the mounting body, the balloon being expandable from a contracted to an expanded state, the stent having an end portion overlying the balloon, the assembly comprising:

first and second cups coaxially mounted on the catheter distal end, each cup having a first end portion overlying a stent end portion, respectively; and

the cups constructed and arranged to retain the stent therebetween on the catheter in the stent reduced condition when the balloon is in the contracted state, the balloon and catheter cooperatively constructed and arranged to cause expansion of the balloon from the contracted to the expanded state to cause expansion of the stent, including the stent end portions, from the reduced to the enlarged condition, and thereby release the stent from abutting the cup end portions.

94. A method for delivering and deploying a stent using the assembly of claim 93, comprising:

providing a catheter having proximal and distal ends and a fluid expandable balloon coaxially mounted over the collar on the catheter distal end;

providing a stent being inflation expandable from a reduced to an enlarged condition;

mounting the stent in the reduced condition coaxially on the balloon so that an end portion of the stent overlies the balloon;

providing first and second cups each having first and second end portions, the cups being in an expanded form and also having a retracted form;

mounting the expanded cups coaxially on the catheter distal end so that the cup first end portions overlie the stent end portions;

contracting the cups about the catheter and the stent end portions to fix the stent to the catheter, the cups cooperating to retain the stent in the reduced condition;

delivering the assembly to a deployment site; and

inflating the balloon to expand the stent to its enlarged condition, whereby the stent is released from the cups.

95. The system according to claim 1, the catheter having a shaft and the inflatable/expandable means being associated therewith at a distal part of the shaft, the securement component comprising mounting and retaining means for receiving the stent on the expandable means for radial expansion of the stent upon expansion of the expandable means, the mounting and retaining means including at least one mounting body carried on the shaft inside the inflatable means whereby the diameter of the shaft and expandable means are increased at the distal part for facilitating the mounting and retaining of the stent, and further including

a sleeve at the distal portion of the catheter, having a first end fixed to the catheter and a second end overlying an end portion of the stent, the sleeve sliding axially to release the stent upon expansion of the expandable means.

96. The stent delivery system of claim 95 wherein the mounting body is of a material which resiliently deforms under radial pressure.

97. The stent delivery system of claim 96 wherein the material is elastomeric.

98. The stent delivery system of claim 96 wherein the material comprises polyurethane.

99. The stent delivery system of claim 95 wherein the stent is crimped to the mounting and retaining means for delivery.

100. The stent delivery system of claim 95 including marker bands positioned on the shaft proximally and distally of the stent.

101. The stent delivery system of claim 95 wherein the expandable means comprises a balloon.

102. The stent delivery system of claim 1, the catheter having a shaft and the inflatable/expandable means associated therewith at a distal part of the shaft, the securement component including mounting and retaining means for receiving the stent to be delivered upon expansion of the inflatable means, the mounting and retaining means including at least one ring-like body inside the expandable means and carried by the shaft, and the stent crimped to the expandable means and the mounting body such that the stent is carried on the shaft and mounting body until expansion of the stent and expandable means, the system further comprising a first and second sleeve in the distal part of the catheter positioned around the catheter, each having a first end fixed to the catheter and a second end overlying first and second end portions of the stent respectively, the first and second sleeves separately fixing the stent before expansion thereof and upon expansion of the expandable means and stent releasing the stent by sliding axially from over the stent.

103. The stent delivery system of claim 102 wherein the stent is generally tubular in shape and the mounting body is generally ring-like in shape.

104. The stent delivery system of claim 102 wherein at least two spaced mounting bodies are included.

105. The stent delivery system of claim 102 wherein at least three spaced mounting bodies are included.

106. The stent delivery system of claim 102 wherein at least four spaced mounting bodies are included.

107. The system according to claim 1, the catheter comprising a shaft, the inflatable means comprising a balloon associated with a distal portion of the shaft for receiving a stent, and means for inflating the balloon, the securement component including at least one ring-like mounting body carried on the shaft inside the balloon whereby the diameter of the shaft is increased inside the balloon to facilitate mounting of a stent to the catheter over the balloon and further including, the system further comprising a first and second sleeve in the distal part of the catheter positioned around the catheter, each having a first end fixed to the catheter and a second end overlying first and second end portions of the stent respectively, the first and second sleeves separately fixing the stent before expansion thereof and upon expansion of the expandable means and stent releasing the stent by sliding axially from over the stent.

26. A method of changing the profile of a balloon catheter for improving the mounting of a stent thereon and providing a catheter for multiple use, comprising the steps of:

providing a balloon catheter of relatively low profile adapted and rearranged for use in an angioplasty procedure;

sliding a stent mounting body to a position associated with the balloon to a position for receiving a stent and enlarging the catheter profile at that position, and mounting a stent on the balloon and mounting body at that position.

27. In a balloon catheter apparatus, the method of enlarging the catheter profile for facilitating the mounting of a stent thereon, comprising:

selectively providing an enlarged mounting body within the balloon in a position to receive a stent.

23. The stent delivery system of claim 29 wherein the coil is enclosed in a polymeric sheath.

28. The method of claim 27 wherein the enlarged body is provided by sliding it into the position.

29. The method of claim 27 wherein the enlarged body is provided by inflating an inner balloon within the catheter balloon.

30. The method of claim 27 wherein the enlarged body is provided by compressing a body already in the position to enlarge its diameter for receiving a stent.

31. The assembly of claim, the inflatable means being an expandable balloon coaxially mounted on the catheter axially within the stent, for expansion of the stent from the delivery diameter to the deployment diameter upon application of fluid deployment pressure to the balloon;

and the securement component being an expandable tube component coaxially mounted on the catheter, axially within the expandable balloon, the tube component designed and adapted for fluid expansion to provide a securement pressure to the stent in the delivery diameter to maintain the stent in position on the catheter during delivery to the deployment site.

32. The assembly according to claim 31, wherein the expandable tube component is sized and constructed to be fluid expandable to no more than the delivery diameter and to no more than the securement pressure.

33. The assembly according to claim 31, wherein the tube component is essentially equal in length to the stent and wherein the stent is positioned on the assembly essentially coextensive with the tube component.

34. The assembly according to claim 32, wherein the tube component is comprised of more than one inflatable pouch.

35. The assembly according to claim 34, wherein the tube component is comprised of three pouches, with a proximal and distal pouch inflatable to a greater pressure than a medial pouch.

36. A method for delivering and deploying a stent using an assembly according to claim 31, comprising:

providing a catheter having proximal and distal ends, with an expandable balloon coaxially mounted on the catheter, and an expandable tube component coaxially mounted on the catheter, axially within the expandable balloon, so that the balloon and the tube component are each in an unexpanded condition;

providing a stent which is expandable from a delivery diameter to a deployment diameter;

mounting the stent, in a diameter greater than the delivery diameter, on the balloon;

contracting the stent to the delivery diameter to conform to an overall profile of the catheter, the tube component and the balloon;

inflating the tube component to provide to the stent a securement pressure to retain the stent in the delivery diameter;

delivering the assembly to a deployment site; and

inflating the balloon to expand the stent to its deployment diameter.

37. The method according to claim 36, wherein the expandable tube component is sized and constructed to be fluid expandable to no more than the delivery diameter.

38. The method according to claim 36, wherein the tube component is essentially equal in length to the stent and wherein the stent is positioned on the assembly essentially coextensive with the tube component.

39. The method according to claim 36, wherein the tube component is comprised of more than one inflatable pouch.

40. The method according to claim 39, wherein the tube component is comprised of three pouches, with a proximal and distal pouch inflatable to a greater pressure than a medial pouch.