Stent having circumferentially deformable struts

• US 20090005854A1
• Filed: 06/29/2007
• Published: 01/01/2009
• Est. Priority Date: 06/29/2007
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Gale, David C., Huang, Bin
• Granted Patent: US 8,057,531 B2
• Time in Patent Office: Days
• US Class Current: 623/1.150
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• 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 2002/9155 Adjacent bands being connected to each other
• CPC Class Codes: A61F 2210/0057 stretchable
• CPC Class Codes: A61F 2250/001 for adjusting a diameter
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2250/0071 breakable or frangible
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/14 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

Disclosed is a method of treating a bodily lumen with a stent, the method comprising: disposing a stent within a bodily lumen, the stent comprising a plurality of deformable struts that are substantially circumferentially aligned and are configured to selectively deform in a circumferential direction in localized regions in the struts upon application of an outward radial force; and expanding the stent by applying the outward radial force, wherein the outward radial force causes selective deformation of the deformable struts in a localized region in the struts.

Claims

1. A method of treating a bodily lumen with a stent, the method comprising:

disposing a stent within a bodily lumen, the stent comprising a plurality of deformable struts that are substantially circumferentially aligned and are configured to selectively deform in a circumferential direction in localized regions in the struts upon application of an outward radial force; and

expanding the stent by applying the outward radial force, wherein the outward radial force causes selective deformation of the deformable struts in a localized region in the struts.

2. The method according to claim 1, wherein the deformable struts include a recess in the localized region, the deformable struts having a smaller cross-sectional area at the recess than the remaining portion of the deformable strut.

3. The method according to claim 2, wherein the recess serves as an initial deforming point in the deformable struts and guides deformation in the circumferential direction upon application of the outward radial force.

4. The method according to claim 1, wherein selective deformation causes the cross-sectional area of the deformable struts adjacent to the recess to be decreased.

5. The method according to claim 1, wherein selective deformation induces crystallization and/or circumferential molecular orientation in the localized region of the deformable struts.

6. The method according to claim 1, wherein selective deformation increases a circumferential mechanical strength and/or modulus in the localized region of the deformable struts.

7. The method according to claim 1, wherein selective deformation increases the crystallinity in the polymer in the localized region of the deformable struts to 30%.

8. The method according to claim 1, wherein selective deformation increases the glass transition temperature of the polymer in the localized region of the deformable struts.

9. The method according to claim 1, wherein the selective deformation comprises circumferential necking in the localized region.

10. The method according to claim 1, wherein selective deformation increases the radial strength of the stent so that the stent is less likely to recoil.

11. The method according to claim 1, wherein selective deformation of the localized region includes lengthening of the deformable struts.

12. The method according to claim 1, wherein selective deformation includes plastic deformation of the deformable struts in the localized regions.

13. The method according to claim 1, wherein the deformable struts include a polymer that is semicrystalline having a T_g in the range of 32°

C. to 44°

C.

14. The method according to claim 1, wherein the deformable struts include a polymer that is selected from the group consisting of poly(glycolic acid), 90:

10 poly(glycolic acid) and polylactide, or mixtures thereof.

15. The method according to claim 1, wherein the stent is expanded and deployed into the lumen after the temperature of the stent increases to body temperature.

16. A method of treating a bodily lumen with a stent, the method comprising:

disposing a stent within a bodily lumen, the stent comprising a plurality of deformable struts having at least one recess, wherein the deformable struts are substantially circumferentially aligned and are configured to selectively deform in a circumferential direction in a localized region at or near the recesses in the struts upon application of an outward radial force; and

expanding the stent by applying the outward radial force, wherein the outward radial force causes selective deformation of the deformable struts in the localized region in the struts.

17. The method according to claim 16, wherein the recess has a cross-sectional area that is smaller than the cross-sectional area of unrecessed portions of the deformable strut.

18. The method according to claim 16, wherein the deformed struts after deformation have a glass transition temperature that is above 37°

C. and a crystallinity of at least 30%.

19. A stent comprising:

a plurality of deformable struts that are substantially circumferentially aligned and are configured to selectively neck in a circumferential direction in a localized region in the struts upon application of an outward radial force, wherein deformable struts are of a semicrystalline polymer material having a glass transition temperature that is below 37°

C. before necking.

20. The stent according to claim 19, wherein the polymeric material is selected from the group consisting of poly(glycolic acid), 90:

10 poly(glycolic acid) and polylactide, or mixtures thereof.