Medical prosthesis

• US 6,419,694 B1
• Filed: 08/26/1998
• Issued: 07/16/2002
• Est. Priority Date: 04/29/1994
• Status: Expired due to Term

• Current Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Sandock, David L.
• Primary Examiner(s): Snow, Bruce
• Application Number:
  US09/140,262
• Publication Number:
  US 20020055771A1
• Time in Patent Office: 1,420 Days
• Field of Search: 623/1.15, 623/1.17, 623/1.22, 623/1.12, 606/194, 606/195, 606/108
• US Class Current: 623/1.22
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body

Abstract

An implantable self-expanding medical prosthesis. The prosthesis has a tube-form body with a body wall structure having a geometric pattern of cells defined by a series of elongate strands extending to regions of intersection and interlocking joints at said regions of intersection formed by a portion of at least one of said strands being helically wrapped about a portion of another.

Claims

1. A self-expanding stent comprising:

a body with a body wall structure having a pattern of cells defined by a plurality of elongate strands extending to regions of intersection, the body having a first compressed position and a second expanded position, each cell having a side that extends in both a circumferential direction and an axial direction at an angle relative to a longitudinal axis of the stent in the expanded position; and

interlocking joints at said regions of intersection formed by a portion of at least one of said strands being helically wrapped about a portion of another strand to form helically wrapped portions, each interlocking joint having a joint axis, which is oriented circumferentially with respect to said body.

2. The stent of claim 1 wherein portions of each of said plurality of strands are helically wrapped about each other.

3. The stent of claim 1 wherein the interlocking joints are constructed such that the axes of said helically wrapped portions of said strands can move relative to each other when the stent is subject to varying radial compressive forces while still maintaining said cell pattern.

4. The stent of claim 1 wherein said interlocking joints are constructed with said strands helically wrapped through a single 360 degree rotation.

5. The stent of claim 1 wherein said strands are metal wires comprising a Nickel-Titanium alloy.

6. The stent of claim 1 further including a sleeve-type covering.

7. The stent of claim 1 wherein the stent has a fully expanded diameter of about 10 mm, and compressible to a diameter of about 9 French.

8. The stent of claim 1 constructed to plastically deform during expansion.

9. The stent of claim 1 constructed of a shape memory material to enable expansion in response to a temperature change.

10. The stent of claim 1 including a drug-delivery layer carried by said wall structure.

11. The stent of claim 1 constructed as a temporary stent, with an end of said stent connected to a drawing member that permits withdrawing of said stent after deployment.

12. The stent of claim 1 wherein each cell has a first cell side having a first length and a second cell side having a second length different than the first length.

13. The stent of claim 1 wherein the joint axis is parallel to the longitudinal axis.

14. The stent of claim 1 wherein the stent is adapted to be bent while maintaining an ovular cross-section, the stent having at least a 80°

-90°

bend.

15. The stent of claim 1 wherein the stent has a length in the compressed position that is longer by 20% or less relative to the length of the stent in the expanded position.

16. A system for treating an occluded body lumen, comprising:

a prosthesis having a tube-form body with a body wall structure having a pattern of cells defined by a series of elongate strands extending to regions of intersection, and interlocking joints at said regions of intersection formed by portions of said strands that are helically wrapped about each other to form helically wrapped portions, each interlocking joint having an axis which is oriented circumferentially with respect to said body, each cell having a side that extends at an angle relative to a longitudinal axis of the body in both a circumferential direction and an axial direction about the body of the prosthesis; and

a delivery catheter constructed to receive said prosthesis in a compressed state for delivery through the body to a desired site in said body lumen, the prosthesis having a length and a diameter in the compressed state, and to allow expansion of said prosthesis to a larger diameter and a smaller length for engaging said body lumen at said desired site.

17. The system of claim 16 wherein said delivery catheter includes a sheath constructed to maintain said prosthesis in compact form during said delivery.

18. The system of claim 16 wherein said interlocking joints are constructed such that the helically wrapped portions of said strands can move relative to each other when the prosthesis is subject to varying radial compressive force while still maintaining said cell structure.

19. The system of claim 16 wherein said interlocking joints are constructed with said strands helically wrapped through at least a single 360 degree rotation.

20. The system of claim 16 wherein said strands are metal wires composed of an Nickel-Titanium alloy.

21. The system of claim 19 fully constructed for use in the biliary system having a fully expanded diameter of about 10 mm, and compressible to a diameter of about 9 French.

22. The system of claim 16 wherein the prosthesis has a plurality of cells each having cell sides of different lengths.

23. An implantable medical prosthesis comprising:

a tube-form body with a body wall structure having a pattern of cells defined by a plurality of elongate strands extending to regions of intersection, the tube-form body having a compressed state and an expanded state; and

interlocking joints formed by a portion of at least one of said strands being helically wrapped about a portion of another said strand, each interlocking joint having an axis extending through the helically wrapped portion, said axis oriented circumferentially with respect to said body, each strand in a cell having a strand angle relative to an axis of a joint in the cell in the range of 35°

-55°

when the tube-form body is in the expanded state.

24. The prosthesis of claim 23 wherein the interlocking joints are constructed such that the axes of said helically wrapped portions of said strands can move relative to each other when the prosthesis is subject to varying radial compressive forces while still maintaining said cell structure.

25. The prosthesis of claim 23 wherein said interlocking joints are constructed with said strands helically wrapped through at least a single 360 degree rotation.

26. The prosthesis of claim 23 wherein said prosthesis is self-expanding.

27. The prosthesis of claim 23 wherein said strands are metal wires composed of a Nickel-Titanium alloy.

28. The prosthesis of claim 23 further including a sleeve-type covering.

29. The prosthesis of claim 23 fully constructed for use in the biliary system having a fully expanded diameter of about 10 mm, and compressible to a diameter of about 9 French.

30. The prosthesis of claim 23 constructed to plastically deform during expansion.

31. The prosthesis of claim 23 constructed of a shape memory material to enable expansion in response to a temperature change.

32. The prosthesis of claim 23 including a drug-delivery layer carried by said wall structure.

33. The prosthesis of claim 23 constructed as a temporary stent, with an end of said stent connected to a drawing member that permits withdrawing of said stent after deployment.

34. The prosthesis of claim 23 including a drug delivery layer carried by said wall structure.

35. The prosthesis of claim 23 constructed as a temporary stent, with an end of said stent connected to a drawing member that permits withdrawing of said stent after deployment.

36. A self-expanding stent comprising:

a body with a body wall structure having a pattern of cells defined by a plurality of elongate strands extending to regions of intersection, the body having a first compressed position and a second expanded position, each cell having a first cell side with a first length and a second length different than the first length; and

interlocking joints at said regions of intersection formed by a portion of at least one of said strands being helically wrapped about a portion of another said strand to form helically wrapped portions, each interlocking joint having an axis which is oriented circumferentially with respect to said body.

37. The stent of claim 36 wherein portions of each of said plurality of strands are helically wrapped about each other.

38. The stent of claim 36 wherein the interlocking joints are constructed such that the axis of said helically wrapped portions of said strands can move relative to each other when the prosthesis is subject to varying radial compressive forces while still maintaining said cell pattern.

39. The stent of claim 36 wherein said interlocking joints are constructed with said strands helically wrapped through a single 360 degree rotation.

40. The stent of claim 36 wherein said strands are metal wires comprising a Nickel-Titanium alloy.

41. The stent of claim 36 further including a sleeve-type covering.

42. The stent of claim 36 constructed for use in the biliary system and having a fully expanded diameter of about 10 mm, and compressible to a diameter of about 9 French.

43. The stent of claim 36 constructed to plastically deform during expansion.

44. The stent of claim 36 constructed of a shape memory material to enable expansion in response to a temperature change.

45. The stent of claim 36 including a drug-delivery layer carried by said wall structure.

46. The stent of claim 36 constructed as a temporary stent, with an end of said stent connected to a drawing member that permits withdrawing of said stent after deployment.