Combined shaped balloon and stent protector

• US 6,764,504 B2
• Filed: 01/04/2001
• Issued: 07/20/2004
• Est. Priority Date: 01/04/2001
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Wang, Lixiao, Chen, John Jianhua
• Primary Examiner(s): NERBUN, PETER P
• Application Number:
  US09/754,661
• Publication Number:
  US 20020120320A1
• Time in Patent Office: 1,293 Days
• Field of Search: 623/1.11, 623/1.12, 623/1.15, 606/194, 606/195, 606/191, 606/192, 606/198, 606/108, 604/96.01, 604/104
• US Class Current: 623/1.11
• 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: A61M 2025/1059 having different inflatable sections mainly depending on the response to the inflation pressure, e.g. due to different material properties with different compartments A61M2025/1072
• CPC Class Codes: A61M 25/1002 characterised by balloon shape A61M25/1006, A61M25/1009 take precedence

Abstract

A stent delivery catheter comprising a catheter shaft and balloon engaged thereto. The balloon being inflatable from a first inflation state to a first expanded state as well as to a second expanded state. The balloon having a stent mounting region for retaining and delivery of a stent therefrom, and at least one adjacent region. The stent mounting region having a first diameter and the at least one adjacent region having a second diameter. In the first inflation state the first diameter being less than the second diameter. In the first expanded state the first diameter being no greater than the second diameter. In the second expanded state the first diameter being greater than the second diameter. The stent being retained on the stent mounting region by engagement of the at least one adjacent portion and at least one retractable stent retaining sleeve.

Claims

1. A stent delivery catheter, the catheter comprising:

a catheter shaft, and

a balloon, the balloon being mounted to the catheter shaft, the balloon when unconstrained being inflatable to a first inflation state at a first pressure where the balloon is nominally inflated by unfolding without substantial expansion and to a second inflation state at a second pressure higher than the first pressure, the balloon having a stent mounting region, at least one adjacent region, and at least one cone region, the at least one adjacent region being positioned between the stent mounting region and the at least one cone region, the stent mounting region having a stent mounting region inner diameter and the at least one adjacent region having an adjacent region inner diameter;

wherein when the balloon is in the first inflation state the stent mounting region inner diameter is less than the adjacent region inner diameter, and when the balloon is in the second inflation state the stent mounting region inner diameter is substantially the same as the adjacent region inner diameter.

2. The stent delivery catheter of claim 1 further comprising a stent, the stent being disposed about at least a portion of the stent mounting region, the stent being expandable from an unexpanded state to a first stent expanded state, the stent further comprising a stent center, a first stent end and a second stent end.

3. The stent delivery catheter of claim 2 further comprising a stent retaining sleeve, the stent retaining sleeve having a stent retaining portion removingly disposed about at least one end of the stent and a catheter engagement portion engaged to a portion of the catheter shaft adjacent to the balloon.

4. The stent delivery catheter of claim 2 further comprising a first stent retaining sleeve and a second stent retaining sleeve, the first stent retaining sleeve having a stent retaking portion removingly disposed about the first stent end and a catheter engagement portion engaged to a first portion of the catheter shaft, the second stent retaining sleeve having a stent retaining portion removingly disposed about the second stent end and a catheter engagement portion engaged to a second portion of the catheter shaft.

5. The stent delivery catheter of claim 4 wherein when the balloon is expanded from the first inflation state to the second inflation state the stent is expanded from the unexpanded state to the first stent expanded state.

9. The stent delivery catheter of claim 4 wherein when the stent is expanded from the unexpanded state to the first stent expanded state the first stent retaining sleeve is configured to retract off of the first stent end, the second stent retaining sleeve is configured to retract off of the second stent end thereby releasing the stent from the first and second stent retaining sleeves.

10. The stent delivery catheter of claim 1 wherein the balloon further comprises a third inflation state, in the third inflation state the stent mounting region diameter being greater than the adjacent region diameter.

11. The stent delivery catheter of claim 10 further comprising a stent, the stent being disposed about at least a portion of the stent mounting region, the stent being expandable from an unexpanded state to a first stent expanded state and to a second stent expanded state, wherein when the balloon is expanded to the third inflation state the stent is expanded to the second stent expanded state.

15. The stent delivery catheter of claim 1 wherein when the balloon is in the first inflation state the stent mounting region diameter is about 1.5 mm to about 2.5 mm.

16. The stent delivery catheter of claim 1 wherein when the balloon is in the first inflation state the adjacent region diameter is about 1.65 mm to about 2.65 mm.

17. The stent delivery catheter of claim 1 wherein when the balloon is in the second inflation state the adjacent region diameter has a range of about 2.0 mm to about 3.75 mm.

18. The stent delivery catheter of claim 1 wherein when the balloon is in the third inflation state the stat mounting region diameter has a range of about 2.75 mm to about 4.25 mm and the adjacent region diameter has a range of about 2.0 mm to 3.75 mm.

19. The stent delivery catheter of claim 1 wherein the balloon is constructed from at least one member of the group consisting of:

thermoplastic polyurethane, polyethylene, polyesters, poly(butylene terephthalate)-block-poly(tetramethylene oxide) polymers, polyetherether ketone, block copolymers of polyether polymers and polyamides, block copolymers of polyether and polyester polymers, polyamides, block polyimides, polytetrafluoroethylene, polyolefins, silicone elastomers, and any combinations thereof.

20. The stent delivery catheter of claim 19 wherein the balloon is at least partially constructed from PEBAN.

21. The stent delivery catheter of claim 10 wherein when the balloon is inflated to a first pressure oft atm to about 3 atm the balloon is in the first inflation state, when the balloon is inflated to a second pressure of more than about 3 atm to about 6 atm the balloon is in the first inflation state, when the balloon is inflated to a third pressure of about 12 atm to about 16 atm the balloon is in the third inflation stare.

23. The stent delivery catheter of claim 1 wherein the adjacent region further comprises a proximal adjacent region anti distal adjacent region.

6. A stent delivery catheter, the catheter comprising:

a catheter shaft;

a balloon, the balloon being mounted to the catheter shaft, the balloon being inflatable to a first inflation state and to a second inflation state, the balloon having a stent mounting region, at least one adjacent region, and at least one cone region, the at least one adjacent region being positioned between the stent mounting region and the at least one cone region, the stent mounting region having a stent mounting region diameter, the at least one adjacent region having an adjacent region diameter and the at least one cone region having a cone region diameter, the balloon having an inflation curve wherein when the balloon is in the first inflation state the stent mounting region diameter is less than the adjacent region diameter, in the second inflation state the stent mounting region diameter is substantially the same as the adjacent region diameter, in both the first inflation state and the second inflation state the cone region diameter is less than the adjacent region diameter;

a stent, the stent being disposed about at least a portion of the stent mounting region, the stent being expandable from an unexpanded state to a first stent expanded state, the stent further comprising a stent center, a first stent end and a second stent end; and

a first stent retaining sleeve and a second stent retaining sleeve, the first stent retaining sleeve having a stent retaining portion removingly disposed about the first stent end and a catheter engagement portion engaged to a first portion of the catheter shaft, the second stent retaining sleeve having a stent retaining portion removingly disposed about the second stent end and a catheter engagement portion engaged to a second portion of the catheter shaft;

wherein when the balloon is expanded from the first inflation state to the second inflation state the stent is expanded from the unexpanded state to the first stent expanded state; and

wherein the stent mounting region is characterized as having a stepped compliance curve and the adjacent region is characterized as having a substantially linear compliance curve, the stepped compliance curve being characterized by a low pressure segment defined by a low inflation pressure range, said low pressure segment being generally collinear with a corresponding segment of the generally linear compliance curve of the at least one adjacent region which is defined by said low inflation pressure range, a transition segment during which the balloon expands rapidly relative to the at least one adjacent region and a high pressure segment during which the compliance curve of the stent mounting region expands slowly relative to the transition segment.

7. The stent delivery catheter of claim 6 wherein when the balloon is inflated to the second inflation state the stent mounting region is expanded according to the transition segment of the stepped compliance curve.

8. The stent delivery catheter of claim 6 wherein when the balloon is inflated to the second inflation state the stent mounting region is expanded according to the low pressure segment of the stepped compliance curve.

12. The stent delivery catheter of claim 6 wherein the balloon further comprises a third inflation state, in the third inflation state the stent mounting region diameter being greater than the adjacent region diameter.

13. The stent delivery catheter of claim 12 wherein when the balloon is inflated to the third inflation state the stent mounting region is expanded according to the transition segment of the stepped compliance curve.

14. The staff delivery catheter of claim 12 wherein when the balloon is inflated to the third inflation state the stent mounting region is expanded according to the high pressure segment of the stepped compliance curve.

22. The stent delivery catheter of claim 12 wherein when the balloon is inflated to a first pressure of greater than about 3 atm to about 6 atm the stent mounting region is in the low pressure segment of the stepped compliance curve and when the balloon is inflated to a third pressure of about 12 atm to about 16 atm the stent mounting region is in the high pressure segment of the stepped compliance curve.

24. A stent delivery catheter comprising:

a catheter shaft;

a balloon, the balloon being mounted to a distal portion of the catheter shaft, the balloon being inflatable to a first inflation state at a first pressure where the balloon is nominally inflated by unfolding without substantial expansion and to a second inflation state at a second pressure higher than the first pressure, the balloon having a stent mounting region, and a pair of balloon regions adjacent to the stoat mounting region, each of the balloon regions being positioned between the stent mounting region and a cone region of the balloon, the pair of balloon regions comprising;

a proximal adjacent region and a distal adjacent region, the stent mounting region having a stent mounting region diameter and each of the adjacent regions having an adjacent region diameter, in the first inflation state the stent mounting region diameter being less than the adjacent region diameter, in the second inflation state the stent mounting region diameter being no greater than the adjacent region diameter;

a stent, the stent being disposed about at least a portion of the stent mounting region, the stent being expandable from an unexpanded state to a first stall expanded state, the stent in the unexpanded state having an outer diameter less than or equal to the outer diameter of at least one of said adjacent regions in the first inflation state, the stent further comprising a stent center, a first stent end and a second stent end; and

a proximal stent retaining sleeve and a distal stent retaining sleeve, each of the stent retaining sleeves having a stent retaining portion and a catheter engagement portion, the stent retaining portion of the distal stent retaining sleeve being removingly disposed about the first stent end, the stent retaining portion of the proximal stent retaining sleeve being removably disposed about the second stent end, the catheter engagement portion of the distal stent retaining sleeve being engaged to a portion of the catheter shaft proximate to the distal adjacent region of the balloon, the catheter engagement portion of the proximal stent retaining sleeve being engaged to a portion of the catheter shaft proximate to the proximal adjacent region of the balloon, whereby when the balloon is inflated from the first inflation state to the second inflation state the at least one stent retaining sleeve is retracted off of the at least one end of the stent.

25. The stent delivery catheter of claim 24 wherein the stent mounting region of the balloon is characterized as having a stepped compliance curve.

26. The stent delivery catheter of claim 25 therein each of the adjacent regions of rite balloon are characterized as having a substantially linear compliance curve.

27. The stent delivery catheter of claim 24 wherein when the balloon is in the second inflation state the stent mounting region diameter is about 0.05 mm to about 0.25 mm less than the adjacent region diameter.

28. The stent delivery catheter of claim 24 wherein the balloon is further characterized as having a third inflation state, when the balloon is inflated to the third inflation state the stent mounting region diameter is greater than the adjacent region diameter.

29. The stent delivery catheter of claim 24 wherein when the balloon is in the third inflation state the stent mounting region diameter is about 0.05 mm to about 0.25 mm greater than the adjacent region diameter.

30. A stent delivery catheter comprising:

a catheter shaft;

a balloon, the balloon being mounted to a distal portion of the catheter shaft, the balloon being inflatable to a first inflation state, to a second inflation slate, and to a third inflation state, the balloon having a stent mounting region and a pair of adjacent end regions, the stent mounting region having a stent mounting region diameter and the pair of end regions each having an end region diameter, in the first inflation state the stent mounting region diameter being less that the end region diameter in the second inflation state the stent mounting region diameter being no greater than the end region diameter, in the third inflation state the stent mounting region diameter being greater than the end region diameter; and

a stent, the stent being disposed about at least portion of the stent mounting region, the stent being expandable from an unexpanded state to an expanded state, the stent further comprising a stent center, a first stent end and a second stent end, the stent in the unexpanded state having an outer diameter less than or equal to the outer diameter of a balloon end region in the first inflation state.

31. The stent delivery catheter of claim 30 further comprising a pair of stent retaining sleeves, each of the stent retaining sleeves having:

a stent retaining portion removingly disposed about one of the ends of the stent, an end region overlaying portion and a catheter engagement portion engaged to a portion of the catheter shaft adjacent to the balloon, whereby when the balloon is inflated from the first inflation state to the second inflation state retaining sleeves are retracted off of the ends of the stent and the end regions of the balloon.

32. A stent delivery catheter comprising:

a catheter shaft;

a balloon, the balloon being mounted to a distal portion of the catheter shaft, the balloon being inflatable to a first inflation state, to a second inflation state, and to a third inflation state, the balloon having a stent mounting region and a pair of adjacent end regions, the stent mounting region having a stent mounting region diameter and the pair of end regions each having an end region diameter, in the first inflation state the stent mounting region diameter being less than the end region diameter, in the second inflation state the stent mounting region diameter being no greater than the end region diameter, in the third inflation state the stent mounting region diameter being greater than the end region diameter;

a stent, the stent being disposed about at least a portion of the stent mounting region, the stent being expandable from an unexpanded state to an expanded state, the stent further comprising a stent center, a first stent end and a second stent end; and

a pair of stent retaining sleeves, each of the stent retaining sleeves having a stent retaining portion removingly disposed about one of the ends of the stent, an end region overlaying portion and a catheter engagement portion engaged to a portion of the catheter shaft adjacent to the balloon, whereby when the balloon is inflated from the first inflation state to the second inflation state the stent retaining sleeves are retracted off of the ends of the stent and the end regions of the balloon;

wherein when the balloon is in the first inflation state and the second inflation state the pair of end regions are engaged to the first stent end and the second stent end respectively, thereby preventing longitudinal movement of the stent relative to the balloon.