Atraumatic Stent and Method and Apparatus for making the same

• US 20140088688A1
• Filed: 12/04/2013
• Published: 03/27/2014
• Est. Priority Date: 01/26/2009
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Lilburn, Steve, Norton, Paul K., Zupkofska, Michael E., Bedard, Louis, Harding, Glenn
• Granted Patent: US 9,388,517 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• 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 2230/0069 cylindrical
• CPC Class Codes: A61F 2240/00 Manufacturing or designing of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: D04C 1/02 made from particular materials
• CPC Class Codes: D04C 1/06 Braid or lace serving particular purposes
• CPC Class Codes: D04C 3/14 Spool carriers
• CPC Class Codes: D04C 3/48 Auxiliary devices
• CPC Class Codes: D10B 2509/06 Vascular grafts; stents

Abstract

A method of braiding a stent includes braiding a number of elongate filaments around a mandrel using tensioned braiding carriers without spooling the filaments to the tensioned braiding carriers to form a braided stent having atraumatic ends.

Claims

1. A stent comprising:

a mesh wall having a variable diameter and comprising filament crossings, each filament crossing having an angle, the angle being substantially constant for all the filament crossings.

2. The stent of claim 1, the mesh wall further comprising atraumatic ends.

3. The stent of claim 1, the mesh wall having end regions with a greater diameter than a middle region extending between the end regions.

4. The stent of claim 1, the filament crossings formed by filaments each comprising a first metal and a second metal, wherein the first metal is nitinol and the second metal is platinum.

5. The stent of claim 1, the filament crossing being non-interlocking.

6. The stent of claim 1, further comprising a polymeric coating comprising silicone.

7. A stent having a variable diameter and comprising composite filaments in a mesh pattern extending from a first stent end to a second stent end, the mesh pattern comprising a plurality of intersections, each intersection having an intersection angle, the intersection angle being uniform throughout the mesh pattern.

8. The stent of claim 7, the mesh pattern being a one-under and one-over pattern.

9. The stent of claim 7, the mesh pattern being a two-under and two-over pattern.

10. The stent of claim 7, each intersection formed by only two filaments.

11. The stent of claim 7, the mesh pattern being non-interlocking.

12. The stent of claim 7, the composite filaments comprising a platinum core with an outer layer of nitinol.

13. The stent of claim 7, wherein the first and second stent ends are atraumatic ends.

14. A braided stent comprising:

a number of elongate filaments inter-braided to form a tubular wall, the filaments being inter-braided at a braiding angle formed at crossing filament locations;

the tubular wall comprising a first portion having a first diameter, a second portion having a second diameter which is different from the second diameter and a transition portion positioned between the first portion and the second portion;

wherein the braiding angles in the first portion, the braiding angles in the second portion, and the braiding angles in the transition portion are substantially equal.

15. The braided stent of claim 14, wherein the braiding angles in the first portion, the second portion, and the transition portion are all within 5 degrees of one and the other.

16. The braided stent of claim 14, wherein the braiding angles in the first portion, the second portion, and the transition portion are all within 1 degree of one and the other.

17. The braided stent of claim 14, wherein the braiding angle is an obtuse angle between longitudinally extending inter-braided filaments.

18. The braided stent of claim 14, wherein at least one of the braiding angles in the first portion, in the second portion or in the transition portion is different from the braiding angles in the other portions.

19. The braided stent of claim 14, wherein the filaments are selected from the group consisting of metallic filaments, polymeric filaments and combinations thereof.

20. The braided stent of claim 14, wherein the filaments are composite filaments comprising a first metal and a second metal, wherein the first metal is nitinol and the second metal is platinum.