Stent with tapered flexibility

• US 20040243216A1
• Filed: 05/28/2003
• Published: 12/02/2004
• Est. Priority Date: 05/28/2003
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated Maple Grove MN
• Inventors: Gregorich, Daniel
• Granted Patent: US 7,112,216 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• 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 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 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility

Abstract

A stent comprises a plurality of serpentine circumferential bands, and a plurality of connector columns. Each connector column is located between two adjacent circumferential bands and comprises one or more connector struts. Each connector strut is connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band. The number of connectors per connector column decreases from the first free end of the stent to the second free end of the stent.

Claims

1. A stent having a first free end and second free end, the stent comprising

a plurality of serpentine circumferential bands, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising one or more connector struts, each connector strut connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

the number of connectors per connector column decreasing from the first free end of the stent to the second free end of the stent.

2. The stent of claim 1 wherein the number of connectors per connector column decreases uniformly from the first free end of the stent to the second free end of the stent.

3. The stent of claim 1 wherein the number of connectors per connector column decreases continuously from the first free end of the stent to the second free end of the stent.

4. The stent of claim 1 wherein one of the connector columns has only a single connector strut.

5. The stent of claim 1 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location.

6. The stent of claim 2 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location.

7. The stent of claim 4 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location.

8. A stent having a first free end and second free end, the stent comprising

a plurality of serpentine circumferential bands, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising one or more connector struts, each connector strut connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

the length of the connectors in a connector column decreasing from the first free end of the stent to the second free end of the stent.

9. The stent of claim 8 wherein the number of connectors per connector column is constant along the length of the stent.

10. The stent of claim 8 wherein the serpentine circumferential bands are uniformly spaced from one another along the length of the stent.

11. The stent of claim 8 wherein each connector strut is substantially straight.

12. The stent of claim 11 wherein each connector strut is inclined at an angle of inclination relative to the longitudinal axis of the stent, the angle of inclination increasing along the length of the stent.

13. The stent of claim 8 wherein each serpentine circumferential band has a first end and a second end and includes a plurality of turns at the first and second ends, the connector struts extending from a turn on one band to a turn on an adjacent band.

14. The stent of claim 8 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location, the circumferential offset between turns which are connected to one another via a connector strut increasing along the length of the stent.

15. The stent of claim 9 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location, turns which are the circumferential offset between turns which are connected to one another via a connector strut increasing along the length of the stent.

16. The stent of claim 10 wherein each connector strut is connected at one end to a first location on a serpentine circumferential band and at another end to a second location on an adjacent serpentine circumferential band, the second location longitudinally and circumferentially offset from the first location, turns which are the circumferential offset between turns which are connected to one another via a connector strut increasing along the length of the stent.

21. The stent of claim 11 wherein each connector strut is inclined at an angle of inclination relative to the longitudinal axis of the stent.

17. A stent having a first free end and second free end, the stent comprising

a plurality of serpentine circumferential bands, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising one or more connector struts, each connector strut characterized by a width and connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

the width of the connectors in a connector column decreasing from the first free end of the stent to the second free end of the stent.

18. The stent of claim 17 wherein the number of connectors per connector column is constant along the length of the stent.

19. The stent of claim 18 wherein the length of the connectors is constant along the length of the stent.

20. The stent of claim 18 wherein each connector strut is substantially straight.

22. A stent having a first free end and second free end, the stent comprising

a plurality of serpentine circumferential bands, each serpentine band having a first end and a second end and characterized by a plurality of turns at the first and second ends, the turns interconnected by band struts, the band struts having a width, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising one or more connector struts, each connector strut characterized by a width and connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

the width of the band struts decreasing from the first free end of the stent to the second free end of the stent.

23. The stent of claim 22 wherein the number of connectors per connector column is constant along the length of the stent.

24. The stent of claim 23 wherein the length of the connectors is constant along the length of the stent.

25. The stent of claim 26 wherein each connector strut is substantially straight.

26. The stent of claim 23 wherein each connector strut is inclined at an angle of inclination relative to the longitudinal axis of the stent.

27. A stent having a first free end and second free end, the stent comprising

a plurality of serpentine circumferential bands, each serpentine circumferential band characterized by a thickness, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising one or more connector struts, each connector strut characterized by a width and connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

the thickness of serpentine circumferential bands decreasing from the first free end of the stent to the second free end of the stent.

28. The stent of claim 27 wherein the number of connectors per connector column is constant along the length of the stent.

29. The stent of claim 28 wherein the length of the connectors is constant along the length of the stent.

30. The stent of claim 27 wherein each connector strut is substantially straight.

31. The stent of claim 30 wherein each connector strut is inclined at an angle of inclination relative to the longitudinal axis of the stent.

32. A stent having a longitudinal axis, a first free end, a midpoint and a second free end, the stent comprising

a plurality of serpentine circumferential bands, and

a plurality of connector columns, each connector column located between two adjacent circumferential bands, each connector column comprising at least one connector strut, each connector strut connected at one end to one serpentine circumferential band and at another end to another serpentine circumferential band,

wherein flexibility of the stent about the longitudinal axis near either endpoint is greater than flexibility of the stent about the longitudinal axis near the midpoint.

33. The stent of claim 32, wherein the number of connector struts in connector columns near the first free end and the second free end of the stent is less than the number of connector struts in connector columns near the midpoint of the stent.

34. The stent of claim 33, wherein the number of connector struts per connector column decreases from the midpoint to the first free end of the stent, and the number of connector struts per connector column decreasing from the midpoint to the second free end of the stent.

35. The stent of claim 32, wherein connector struts in connector columns near the first free end and the second free end of the stent are longer than connector struts in connector columns near the midpoint of the stent.

36. The stent of claim 35, wherein the length of the connector struts increases from the midpoint to the first free end of the stent, and length of the connector struts increases from the midpoint to the second free end of the stent.

37. The stent of claim 32, wherein the thickness of connector struts near the midpoint of the stent is greater than the thickness of connector struts near either end of the stent.

38. The stent of claim 37, wherein the thickness of the stent decreases continuously from the midpoint of the stent to either end of the stent.