High strength member for intracorporeal use

• US 6,827,734 B2
• Filed: 05/23/2002
• Issued: 12/07/2004
• Est. Priority Date: 07/25/1994
• Status: Expired due to Fees

• Current Assignee: Advanced Cardiovascular Systems Incorporated
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Fariabi, Sepehr
• Primary Examiner(s): McDermott, Corrine
• Assistant Examiner(s): Phan, Hieu
• Application Number:
  US10/154,474
• Publication Number:
  US 20020147494A1
• Time in Patent Office: 929 Days
• Field of Search: 623/1.15, 623/1.16, 623/1-7-
• US Class Current: 623/1.18
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61M 2025/09083 having a coil around a core
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 25/0012 with embedded structures, e.g. coils, braids, meshes, strands or radiopaque coils
• CPC Class Codes: A61M 25/09 Guide wires

Abstract

This invention is directed to an intracorporeal device formed of a high strength Co—Ni—Cr alloy and is particularly suitable for forming a composite product with a pseudoelastic member formed of NiTi alloy. Suitable intracorporeal products include guidewires and stents. The high strength alloy consists essentially of about 28 to about 65% cobalt, about 2 to about 40% nickel, about 5 to about 35% chromium, up to about 12% molybdenum, up to about 20% tungsten, up to about 20% iron and the balance inconsequential amounts of impurities and other alloying constituents, with a preferred alloy composition including about 30 to about 45% cobalt, about 25 to about 37% nickel, about 15 to about 25% chromium and about 5 to about 15% molybdenum. Intravascular devices such as guidewires, stents and the like can be formed of this high strength Co—Ni—Cr alloy.

Claims

1. A stent comprising a cylindrically shaped tubular member having a plurality of non-helical cylindrical elements joined integrally by interconnecting members and further having metallic undulating structural elements wherein the entire cross-section of each metallic undulating structural element is composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, chromium in a concentration of between about 5 to about 35 percent by weight, and nickel in a concentration of about 2 to about 40 percent by weight;

and the cylindrically shaped tubular member is configured to be plastically expanded by an expandable member to a desired self supporting diameter suitable to hold open a body lumen.

2. The stent of claim 1, wherein the alloy further comprises molybdenum in a concentration up to about 12 percent by weight.

3. The stent of claim 1, wherein the alloy further comprises tungsten in a concentration up to about 20 percent by weight, iron in a concentration up to about 20 percent by weight, and manganese in a concentration up to about 3 percent by weight.

4. The stent of claim 1, wherein the alloy further comprises molybdenum in a concentration up to about 12 percent by weight, tungsten in a concentration up to about 20 percent by weight, iron in a concentration up to about 20 percent by weight, and manganese in a concentration up to about 3 percent by weight.

5. The stent of claim 1, wherein the cylindrically shaped tubular member includes a cylindrical element shaped in a serpentine pattern.

6. The stent of claim 1, wherein the cylindrically shaped tubular member includes a plurality of cylindrical elements joined together by interconnecting elements.

7. The stent of claim 6, wherein there are at least three interconnecting elements between adjacent cylindrical elements.

8. The stent of claim 1, further comprising metallic undulating structural elements being plastically expandable in a blood vessel for deployment therein.

9. The stent of claim 8, wherein the tubular member has a reticulated tubular structure having bounded openings for blood perfusion.

10. The stent of claim 9, wherein the reticulated tubular structure has a continuum body made from tubing.

11. The stent of claim 10, wherein the tubular structure has electrochemically polished tubular internal and external surfaces.

12. A stent comprising a tubular member having a plurality of non-helical cylindrical elements joined integrally by interconnecting members and further having metallic undulating structural elements wherein the entire cross-section of the metallic undulating structural elements is composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, chromium in a concentration of between about 5 to about 35 percent by weight, and nickel in a concentration of between about 2 to about 40 percent by weight.

13. The stent of claim 12, wherein the alloy further comprises iron in a concentration of less than about 20 percent by weight, and manganese in a concentration of less than about 3 percent by weight.

14. The stent of claim 13, wherein the alloy further comprises molybdenum in a concentration of less than about 12 percent by weight.

15. The stent of claim 14, wherein the alloy further comprises tungsten in a concentration of less than about 20 percent by weight.

16. The stent of claim 12, wherein the tubular member is balloon expandable.

17. The stent of claim 12, wherein the tubular member includes a plurality of cylindrical elements each having a serpentine pattern.

18. The stent of claim 17, wherein the serpentine pattern is in-phase with adjacent cylindrical elements.

19. The stent of claim 17, wherein the serpentine pattern is out of phase with adjacent cylindrical elements.

20. A stent comprising a plurality of radially expandable cylindrical elements composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, chromium in a concentration of between about 5 to about 35 percent by weight, nickel in a concentration of about 2 to about 40 percent by weight, tungsten in a concentration of up to about 20 percent by weight, iron in a concentration of up to about 20 percent by weight, and manganese in a concentration of up to about 3 percent by weight.

21. The stent of claim 20, wherein the alloy further includes molybdenum in a concentration of up to about 12 percent by weight.

22. The stent of claim 20, wherein the cylindrical elements are dimensioned to be longitudinally shorter than their own diameters.

23. The stent of claim 22, further including interconnecting elements disposed between adjacent cylindrical elements, wherein there are three interconnecting elements between adjacent cylindrical elements.

24. A stent comprising:

a plurality of radially expandable cylindrical elements;

the cylindrical elements composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, chromium in a concentration of between about 5 to about 35 percent by weight, and nickel in a concentration of about 2 to about 40 percent by weight;

the cylindrical elements having an undulating component with a relatively flat cross-section; and

the cylindrical elements configured to be plastically expanded by an expandable member to a desired self supporting diameter suitable to hold open a body lumen.

25. A stent comprising:

a plurality of radially expandable, non-helical cylindrical elements;

the cylindrical elements having metallic undulating structural elements wherein the entire cross-section of the metallic undulating structural elements is composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, chromium in a concentration of between about 5 to about 35 percent by weight, and nickel in a concentration of about 2 to about 40 percent by weight;

the cylindrical elements configured to be plastically expanded by an expandable member to a desired self supporting diameter suitable to hold open a body lumen;

the cylindrical elements having an electrochemically polished metallic surface; and

the cylindrical elements having been cold worked and age hardened.

26. The stent of claim 25, wherein the cylindrical elements have an undulating component with a relatively flat cross-section.

27. The stent of claim 26, wherein at least one of the cylindrical elements is out of phase with at least another one of the cylindrical elements.

28. A stent comprising:

a plurality of radially expandable cylindrical elements;

the cylindrical elements composed of an alloy including cobalt in a concentration of between about 28 to about 65 percent by weight, the alloy further including chromium, nickel, and tungsten;

the cylindrical elements configured to be plastically expanded by an expandable member to a desired self supporting diameter suitable to hold open a body lumen.

29. The stent of claim 28, wherein the alloy includes tungsten in a concentration up to about 20 percent by weight.

30. The stent of claim 28, wherein the percent by weight of chromium is between about 5 to about 35 percent and the percent by weight of nickel is about 2 to about 40 percent.

31. The stent of claim 28, wherein the cylindrical elements have a electrochemically polished surface and a biocompatible coating on the electrochemically polished surface.

32. The stent of claim 28, wherein the cylindrical elements have an undulating component with a relatively flat cross-section.

33. The stent of claim 32, wherein at least one of the cylindrical elements is out of phase with at least another one of the cylindrical elements.

34. The stent of claim 32, wherein the cross-section of the undulating component of the cylindrical elements has an aspect ratio of about one to one.

35. The stent of claim 32, wherein the cross-section of the undulating component of the cylindrical elements has a height-to-width aspect ratio of about two-to-one.

36. The stent of claim 30, further comprising undulations being plastically expandable in a blood vessel for deployment therein.

37. The stent of claim 36, wherein the plurality of radially expandable cylindrical elements have a reticulated tubular structure having bounded openings for blood perfusion.

38. The stent of claim 37, wherein the reticulated tubular structure has a continuum body made from tubing.

39. The stent of claim 38, wherein the plurality of radially expandable cylindrical elements have electrochemically polished tubular internal and external surfaces.