Intravascular stent

• US 6,152,957 A
• Filed: 03/26/1997
• Issued: 11/28/2000
• Est. Priority Date: 04/26/1996
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Jang G. David
• Inventors: Jang, G. David
• Primary Examiner(s): Milano, Michael J.
• Assistant Examiner(s): Phan, Hieu
• Application Number:
  US08/824,865
• Time in Patent Office: 1,343 Days
• Field of Search: 623/1, 623/12, 623/1.37, 623/1.1, 606/195, 606/198
• US Class Current: 623/1.37
• 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 2/958 Inflatable balloons for placing stents or stent-grafts
• 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 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility

Abstract

A stent assembly includes a balloon and an expandable stent positioned at an exterior of the balloon. The stent includes a first expansion strut. A plurality of the first expansion struts form a first expansion column. A plurality of second expansion struts form a second expansion column. A plurality of the first connecting struts form a first connecting strut column. Each of a first expansion strut of the first expansion column is coupled to a second expansion strut of the second expansion column. The first connecting strut includes a proximal section coupled to a distal section and at least a portion of the first connecting strut includes a first linear section and a first slant angle.

Claims

1. A stent in a non-expanded state, comprising:

a first expansion strut pair including a first expansion strut positioned adjacent to a second expansion strut and a joining strut of the first expansion strut pair that couples the first and second expansion struts at a distal end of the first expansion strut pair, a plurality of the first expansion strut pair forming a first expansion column;

a second expansion strut pair including a first expansion strut positioned adjacent to a second expansion strut and a joining strut of the second expansion strut pair that couples the first and second expansion struts of the second expansion strut pair at a proximal end of the second expansion strut pair, a plurality of the second expansion strut pair forming a second expansion column;

a first connecting strut including a first connecting strut proximal head section and first connecting strut distal tail section, the head section being coupled to the distal end of the first expansion strut pair in the first expansion column and the tail section being coupled to the proximal end of the second expansion strut pair of the second expansion column, a plurality of the first connecting strut forming a first connecting strut column that couples the first expansion column to the second expansion column, the tail section extending in a first lateral direction relative to a longitudinal axis of the head section to form a first slant angle;

a third expansion strut pair including a first expansion strut positioned adjacent to a second expansion strut and a third joining strut of the third expansion strut pair that couples the first and second expansion struts at a proximal end of the third expansion strut pair, a plurality of the third expansion strut pair forming a third expansion column, the first expansion strut of the first expansion strut pair in the first expansion column having a longitudinal axis that is parallel to and offset from a longitudinal axis of the first expansion strut of the second expansion strut pair in the second expansion column, and the second expansion strut of the third expansion strut pair in the third expansion column having a longitudinal axis that is parallel to and offset from a longitudinal axis of the first expansion strut of the second expansion strut pair of the second expansion column;

a second connecting strut including a proximal head section and a distal tail section, the head section being coupled to the distal end of the second expansion strut pair in the second expansion column and the tail section being coupled to the proximal end of the third expansion strut pair of the third expansion column, a plurality of the second connecting strut forming a second connecting strut column that couples the second expansion column to the third expansion column, wherein the tail section extends in a second lateral direction relative to a longitudinal axis of the head section to form a second slant angle that extends in an opposite direction from the first lateral direction; and

wherein a ratio of a number of expansion struts in an expansion strut column to a number of connecting struts in a connecting strut column is 2 to 1 and the first slant angle reduces a fore shortening of the stent between the first and second expansion columns when the stent is in an expanded state.

2. The stent of claim 1, wherein the stent includes m first and second expansion columns, n expansion struts per column and n (m-1)/2 connecting struts.

3. The stent of claim 1, wherein the first and second expansion columns are each unbroken, continuous structures.

4. The stent of claim 1, wherein each of the first slant angles is directed in a first circumferential direction.

5. The stent of claim 1, wherein the first connecting strut includes a third slant angle.

6. The stent of claim 1, wherein a width of a portion of the first connecting struts is equal to or less than a width of a portion of the first expansion struts.

7. The stent of claim 1, wherein a width of a portion of the first connecting struts is larger than a width of a portion of the first expansion struts.

8. The stent of claim 1, wherein a width of a portion of the second expansion struts is substantially the same as a width of a portion of the first expansion struts.

9. The stent of claim 1, further comprising:

a reenforcement expansion column made of a plurality of reenforcement expansion struts, wherein each reenforcement expansion strut has a width that is greater than a width of an expansion strut in the first or second expansion columns.

10. The stent of claim 1, wherein the stent has a proximal end with a first reenforcement expansion column and a distal end with a second reenforcement expansion column.

11. The stent of claim 1, wherein at least a portion of the first connecting struts have a first radius of curvature.

12. The stent of claim 11, wherein the portion of the first connecting struts with the first radius of curvature have a second radius of curvature.

13. The stent of claim 1, wherein at least a portion of the first connecting struts have first linear sections coupled to joining struts of first expansion strut pairs and second linear sections coupled to joining struts of second expansion strut pairs.

14. The stent of claim 1, wherein at least a portion of the first connecting struts have first linear sections coupled to joining struts of first expansion strut pairs, second linear sections coupled to joining struts of second expansion strut pairs and third linear sections coupling the first and second linear sections.

15. The stent of claim 1, wherein at least a portion of the first connecting struts have first linear sections coupled to joining struts of first expansion strut pairs, second linear sections coupled to joining struts of second expansion strut pairs, third and fourth linear sections coupling the first and second linear sections.

16. The stent of claim 1, wherein the stent further includes a radiopaque marker.

17. The stent of claim 1, wherein the stent includes an electroplated material.

18. The stent of claim 1, wherein in an expanded state the stent has a tapered diameter.

30. The stent of claim 1, wherein the stent has a tapered diameter in an expanded state.

31. The stent of claim 1, wherein the stent has a tapered geometry extending from a proximal end to a distal end in an expanded state.

38. The stent of claim 1, wherein the stent includes an electroplated material at a stent proximal end and at a stent distal end.

19. A stent assembly, comprising:

a balloon; and

an expandable stent positioned at an exterior of the balloon, the stent including,

a first expansion strut, a plurality of the first expansion strut forming a first expansion column;

a second expansion strut, a plurality of the second expansion strut forming a second expansion column; and

a first connecting strut, a plurality of the first connecting strut forming a first connecting strut column, each of a first connecting strut connecting a first expansion strut of the first expansion column to a second expansion strut of the second expansion column, the first connecting strut including a proximal section coupled to a distal section and at least a portion of the first connecting strut including a first linear section and a first slant angle.

20. The assembly of claim 19, wherein the balloon has a tapered geometry.

21. The assembly of claim 19, wherein a proximal end and a distal end of the connecting strut are circumferentially offset from each another when the stent is in a non-expanded state.

22. The assembly of claim 19, wherein a proximal end and a distal end of the connecting strut are circumferentially offset from each another when the stent is in an expanded state.

23. The assembly of claim 19, wherein a ratio of a number of expansion struts in an expansion strut column to a number of connecting struts in an connecting strut column is 2 to 1.

24. The assembly of claim 19, wherein the connecting strut has a geometry which provides for a reduction of a fore shortening of the stent between the first and second expansion columns when the stent is in an expanded state.

25. The assembly of claim 19, wherein the stent includes m first and second expansion columns, n expansion struts per column and n (m-1)/2 connecting struts.

26. The stent of claim 19, wherein the first and second expansion columns are each unbroken, continuous structures.

27. The stent of claim 19, wherein each first connecting strut first slant angle is directed in a first circumferential direction.

28. The stent of claim 19, wherein the first connecting strut includes a second slant angle.

29. The stent of claim 19, wherein the first expansion strut of the first expansion column is longitudinally offset from a corresponding second expansion strut of the second expansion column.

32. The stent assembly of claim 19, wherein the balloon is tapered in an expanded state.

33. The stent assembly of claim 32, wherein the balloon in an expanded state is curved along a longitudinal axis from a proximal end to a distal end.

34. The stent assembly of claim 32, wherein the balloon is tapered in an expanded state and the stent has a non-tapered geometry in an expanded state.

35. The stent assembly of claim 32, wherein the balloon and the stent are both tapered in an expanded state.

36. The stent assembly of claim 33, wherein the stent is non-tapered in an expanded state.

37. The stent assembly of claim 33, wherein the stent is tapered in an expanded state.