Multilayer stents having enhanced flexibility and hoop strength

• US 20020013616A1
• Filed: 05/04/2001
• Published: 01/31/2002
• Est. Priority Date: 05/05/2000
• Status: Abandoned Application

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford University)
• Inventors: Carter, Andrew, Deng, Hsin-Yi, Pierce, Ryan Kendall
• Application Number:
  US09/848,962
• Publication Number:
  US 20020013616A1
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• 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 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

Multilayer stents, as well as methods for their use and kits comprising the same, are provided. The subject multilayer stents include at least two distinct layers or structures concentrically arranged in a manner sufficient to provide a multilayer stent that exhibits enhanced flexibility in a compressed state and enhanced hoop strength in an expanded state, as compared to a single layer stent of the same thickness. The subject multilayer stents find use in a variety of different applications, including vascular applications in which the stents are implanted into the vascular system of a patient.

Claims

1. A multilayer stent, said stent comprising:

at least two layers having a combined wall thickness W, wherein said multilayer stent is capable of going from a first compressed state to a second expanded state and exhibits enhanced flexibility in said first compressed state and enhanced hoop strength in said second expanded state as compared to a single layer stent of wall thickness W.

2. The multilayer stent according to claim 1, wherein W ranges from about 0.02 to 3 mm.

3. The multilayer stent according to claim 1, wherein said first and second layers are arranged relative to one another in a manner sufficient to provide for said enhanced flexibility and hoop strength.

4. The multilayer stent according to claim 1, wherein said at least two layers have tubular, coil, mesh or graft configurations.

5. The multilayer stent according to claim 1, wherein said at least two layers have the same configuration.

6. The multilayer stent according to claim 1, wherein said stent comprises two layers.

7. The multilayer stent according to claim 1, wherein said at least two layers are attached to each other at at least one location.

16. In a method in which a stent is deployed in a physiological location, the improvement comprising:

employing a multilayer stent according to claim 1 in said procedure.

17. The method according to claim 16, wherein said physiological location is an intravascular site.

18. A kit comprising:

a stent according to claim 1; and

instructions for using said stent.

19. The kit according to claim 18, wherein said kit comprises a stent deployment means.

20. The kit according to claim 18, wherein said deployment means comprises a balloon catheter.

8. A dual layer stent comprising:

a first tubular structure of wall thickness X; and

a second tubular structure of wall thickness Y;

wherein said first and second tubular structures are concentrically arranged so as to produce a dual layer stent capable of going from a first compressed state to a second expanded state, wherein said dual layer stent exhibits enhanced flexibility in said first compressed state and enhanced hoop strength in said second expanded state as compared to a single layer stent of wall thickness W, wherein X+Y=W.

9. The dual layer stent according to claim 8, wherein W ranges from about 0.02 to 3 mm.

10. The dual layer stent according to claim 8, wherein said first and second tubular structures are welded to each other at least one site.

11. The dual layer stent according to claim 8, wherein said first and second tubular structures have the same configuration.

12. A dual layer stent comprising:

first and second concentric tubular structures having the same the configuration and of identical wall thickness X ranging from about 0.002″

to 0.02″

, wherein said concentric tubular structures are arranged so as to produce a dual layer stent capable of going from a first compressed state to a second expanded state, wherein said dual layer stent exhibits enhanced flexibility in said first compressed state and enhanced hoop strength in said second expanded state as compared to a single layer stent of wall thickness 2X.

13. The dual layer stent according to claim 12, wherein said dual layer stent exhibits a longitudinal flexibility in said first compressed state ranging from about 0.03 to 0.05 kgf/mm.

14. The dual layer stent according to claim 12, wherein said dual layer stent exhibits a hoop strength in said second expanded state ranging from about 0 to 5% recoil.

15. The dual layer stent according to claim 12, wherein said first and second tubular structures have a configuration substantially similar to or identical to the structures shown in FIG. 1.