EXPANDABLE STENT THAT COLLAPSES INTO A NON-CONVEX SHAPE AND EXPANDS INTO AN EXPANDED, CONVEX SHAPE

• US 20110251670A1
• Filed: 04/07/2011
• Published: 10/13/2011
• Est. Priority Date: 04/07/2010
• Status: Active Grant

• Current Assignee: California Institute of Technology, University of South Carolina
• Original Assignee: California Institute of Technology, University of South Carolina
• Inventors: Gharib, Morteza, Kheradvar, Arash
• Granted Patent: US 8,702,788 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

An expandable stent that can transform between a collapsed state and an expanded state is described. The stent includes a first cross-sectional shape and a second cross-sectional shape. The first cross-sectional shape is a non-convex shape when the stent is in the collapsed state. Alternatively, the second cross-sectional shape is a convex shape when the stent is in an expanded state. The stent can be formed of super elastic Nitinol, which allows it to be shape set in the desired shape. Due to its shape setting properties and the non-convex cross-section, the stent is capable of dramatically reducing its cross-sectional radial profile which is beneficial in a variety of procedures.

Claims

1. An expandable construct that can transform between a collapsed state and an expanded state, comprising:

a first cross-sectional shape, the first cross-sectional shape being a non-convex shape when the expandable construct is in a collapsed state.

2. The expandable construct as set forth in claim 1, wherein the expandable construct also includes a second cross-sectional shape, the second cross-sectional shape being a convex shape when the expandable construct is in an expanded state.

3. The expandable construct as set forth in claim 2, wherein the construct is a stent.

4. The expandable construct as set forth in claim 1, wherein the construct is a stent that is formed of a dissolving material.

5. The expandable construct as set forth in claim 1, wherein the expandable construct also includes a second cross-sectional shape, the second cross-sectional shape being a non-convex shape when the expandable construct is in an expanded state.

6. The expandable construct as set forth in claim 1, wherein the expandable construct includes a length and is formed such that a cross-sectional shape is unequal along its length.

7. The expandable construct as set forth in claim 1, wherein the construct is a stent and the stent is expandable from the collapsed state to the expanded state, such that upon expansion, the stent transforms from having the first cross-sectional non-convex shape into the second cross-sectional convex shape.

8. The expandable construct as set forth in claim 1, wherein the construct is made of elastic material.

9. The expandable construct as set forth in claim 1, wherein the construct is made of a material selected from a group consisting of a super elastic material, a shape-memory material, and a magnetic memory material.

10. The expandable construct as set forth in claim 1, wherein the construct is made of a material selected from a group consisting of a super elastic Nitinol and a shape-memory Nitinol.

11. The expandable construct as set forth in claim 1, wherein the construct is a component of a heart valve.

12. The expandable construct as set forth in claim 1, wherein the construct is a component of a corollary stent system.

13. The expandable construct as set forth in claim 1, wherein the construct is a ureteral stent.

14. The expandable construct as set forth in claim 1, wherein the construct is a prostatic stent.

15. The expandable construct as set forth in claim 1, wherein the construct is drug coated to operate as a drug eluting stent.

16. The expandable construct as set forth in claim 1, wherein the construct is a component of a peripheral artery angioplasty.

17. The expandable construct as set forth in claim 1, wherein construct is a component of a stent graft used for endovascular surgery.

19. The method as set forth in claim 15, wherein in collapsing a construct radially, the construct is a stent.

18. A method for forming a construct, comprising acts of:

collapsing a construct radially to have a cross-sectional convex shape;

applying a load to at least one location on the construct to form a collapsed construct having a cross-sectional non-convex shape; and

shape setting the construct to having a shape set cross-sectional non-convex shape.

20. A method for applying a stent to a desired location, comprising acts of:

inserting a collapsed stent having a cross-sectional non-convex shape into a user until reaching a desired location; and

causing the collapsed stent to transform into an expanded stent having a cross-sectional convex shape.