Stent having struts with reverse direction curvature

• US 20050273157A1
• Filed: 06/08/2004
• Published: 12/08/2005
• Est. Priority Date: 06/08/2004
• Status: Active Grant

• Current Assignee: Medinol Limited (Medinol USA Incorporated)
• Original Assignee: Medinol Limited (Medinol USA Incorporated)
• Inventors: Pinchasik, Gregory
• Granted Patent: US 7,763,064 B2
• Time in Patent Office: Days
• US Class Current: 623/1.150
• 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 2250/0036 differing in thickness

Abstract

Disclosed is a stent having struts with reverse direction curvature for providing a reduced compressed profile and an increased expanded profile. The strut configuration comprises a plurality of arcuate sections facing in opposite convex and a concave orientation. The strut width may be gradually decreased from its ends towards the strut'"'"'s mid-section to redistribute maximal strains away from portions of the stent more susceptible to permanent deformation, such as the loop portions. Varying strut lengths to offset the maximum circumferential widths of adjacent portions of the stent may further reduce the compressed stent profile. The varied stent lengths may also contribute to an increased expanded stent profile. Stents with the reverse direction curvature strut design can obtain an expanded to compressed stent diameter ratio of about 7:1 compared to conventional stents that have a ratio of up to about 5:1. The curved strut can be utilized with any stent design.

Claims

1. A stent, comprising:

a plurality of interconnected circumferential bands defining a cylindrical structure having a longitudinal axis;

each of the circumferential bands having a generally serpentine pattern and comprising a plurality of struts and a plurality of loops, wherein each end of a strut is coupled to an end of a loop; and

at least one of the circumferential bands having at least two struts comprising a plurality of arcuate sections, wherein each arcuate section in the strut has an opposite curvature to that of an adjacent arcuate section in the strut.

2. The stent according to claim 1, wherein the plurality of arcuate sections in the strut substantially straighten and extend when the stent is compressed.

3. The stent according to claim 1, wherein each strut with arcuate sections has a cross-sectional area that gradually decreases in opposing directions from the ends of the strut, the ends of the strut having greater cross-sectional area than the mid-section of the strut.

4. The stent according to claim 1, wherein said stent is self-expanding.

5. The stent according to claim 1, wherein said stent is balloon-expandable.

6. The stent according to claim 1, wherein the width of the loop is greater than the width of the strut.

7. The stent according to claim 4, wherein the stent has an expanded to compressed outside diameter ratio of greater than about 5:

1.

8. The stent according to claim 4, wherein the stent has an expanded to compressed outside diameter ratio of about 7:

1.

9. The stent according to claim 1, wherein maximal strain imparted on the stent when the stent is compressed is distributed toward the mid-section of the struts.

10. The stent according to claim 1, wherein said at least one circumferential band includes at least one set of two struts with arcuate sections coupled to the ends of one loop, said set of loop and struts having a maximum circumferential width when the stent is compressed, the maximum circumferential width of each set of loop and struts being offset along the longitudinal axis from maximum circumferential widths of adjacent sets of loop and struts when the stent is compressed.

11. The stent according to claim 10, wherein the maximum circumferential widths of adjacent sets of loop and struts are offset along the longitudinal axis by varying the lengths of the struts.

12. A stent, comprising:

a plurality of interconnected circumferential bands defining a cylindrical structure having a longitudinal axis;

each of the circumferential bands having a generally serpentine pattern and comprising a plurality of struts and a plurality of loops, wherein each end of a loop is coupled to an end of two adjacent struts; and

at least one circumferential band having struts comprising a plurality of arcuate sections, wherein each arcuate section in the strut has an opposite curvature to that of an adjacent arcuate section in the strut and each strut has a varying width wherein the width at ends of the strut are larger than the width of the remainder of the strut.

13. The stent according to claim 12, wherein the plurality of arcuate sections in the struts substantially straighten and extend when the stent is compressed.

14. The stent according to claim 12, wherein each strut with arcuate sections has a cross-sectional area that gradually decreases in opposing directions from the ends of the strut, the ends of the strut having greater cross-sectional area than the mid-section of the strut.

15. The stent according to claim 12, wherein said stent is self-expanding.

16. The stent according to claim 12, wherein said stent is balloon-expandable.

17. The stent according to claim 12, wherein said loop is wider than said strut.

18. The stent according to claim 15, wherein the stent has an expanded to compressed outside diameter ratio of greater than about 5:

1.

19. The stent according to claim 15, wherein the stent has an expanded to compressed outer diameter ratio of about 7:

1.

20. The stent according to claim 12, wherein said at least one circumferential band comprises a multiplicity of sets of two adjacent struts coupled to the ends of a loop, each set of loop and struts having a maximum circumferential width when the stent is compressed, the maximum circumferential widths of adjacent sets of loop and struts being offset along the longitudinal axis when the stent is compressed.

21. The stent according to claim 20, wherein the maximum circumferential widths of adjacent sets of loop and struts are offset along the longitudinal axis by varying the lengths of the struts.

22. A stent defining a cylindrical structure having a longitudinal axis comprising a plurality of cells, each of the plurality of cells comprising:

a first circumferential section having a generally serpentine pattern and comprising a plurality of struts and at least one loop, the struts and loops forming at least one set of two struts coupled to the ends of one loop;

a second circumferential section having a generally serpentine pattern and comprising a plurality of struts and at least one loop; and

at least one of the sets of the first circumferential section having two struts comprising a plurality of arcuate sections, wherein each arcuate section has an opposite curvature to that of an adjacent arcuate section, and each strut has a varying width wherein the width at ends of the strut are larger than the width of the remainder of the strut and the loop has a greater width than the strut.

23. The stent according to claim 22, wherein the plurality of arcuate strut sections substantially straighten when the stent is compressed.

24. The stent according to claim 22, wherein each strut with arcuate sections has a cross-sectional area that gradually decreases in opposing directions from the ends of the strut, the ends of the strut having greater cross-sectional area than the mid-section of the strut.

25. The stent according to claim 22, wherein the stent is self-expanding.

26. The stent according to claim 22, wherein said stent is balloon-expandable.

27. The stent according to claim 22, wherein said loop is wider than said strut.

28. The stent according to claim 25, wherein the stent has an expanded to compressed outside diameter ratio of greater than about 5:

1.

29. The stent according to claim 25, wherein the stent has an expanded to compressed outside diameter ratio of about 7:

1.

30. The stent according to claim 22, wherein each set of loop and struts in the first circumferential section has a maximum circumferential width when the stent is compressed, the maximum circumferential width of each set of loop and struts being offset along the longitudinal axis from maximum circumferential widths of adjacent sets of loop and struts when the stent is compressed.

31. The stent according to claim 30, wherein the maximum circumferential widths of adjacent sets of loop and struts are offset along the longitudinal axis by varying the lengths of the struts.