STENT DESIGNS AND METHODS OF MANUFACTURE

• US 20150045874A1
• Filed: 08/08/2014
• Published: 02/12/2015
• Est. Priority Date: 08/09/2013
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: McMahon, Shane, Keating, Thomas Martin, Ryan, Conor, Hingston, John Allen
• Granted Patent: US 9,469,925 B2
• Time in Patent Office: Days
• US Class Current: 623/1.22
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: A61L 31/10 Macromolecular materials
• CPC Class Codes: B29C 53/36 Bending and joining, e.g. for making hollow articles B29C53/56 takes precedence
• CPC Class Codes: B29C 65/08 using ultrasonic vibrations non-plastics element to plastics elements B29C65/645
• CPC Class Codes: B29C 65/16 Laser beams
• CPC Class Codes: B29C 66/5221 for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other
• CPC Class Codes: B29K 2067/003 PET, i.e. poylethylene terephthalate
• CPC Class Codes: B29K 2995/0056 Biocompatible, e.g. biopolymers or bioelastomers
• CPC Class Codes: B29K 2995/006 Bio-degradable, e.g. bioabsorbable, bioresorbable or bioerodible
• CPC Class Codes: D04C 3/12 with means for introducing core threads
• CPC Class Codes: D04C 3/48 Auxiliary devices

Abstract

Embodiments disclosed include a woven stent and a method of manufacturing a woven stent that includes a plurality of first members and a plurality of second members forming a braided configuration; wherein each of the first members includes a first body portion, a first end unjoined portion, and a first end bent portion; wherein each of the second members includes a first end overlap portion extending alongside the first end unjoined portion. The woven stent may further includes a coating that encapsulates the first end unjoined portions and the first end overlap portions and/or the first end unjoined portions may be laser joined or ultrasonic joined to the first end overlap portions.

Claims

1. A woven stent comprising:

a tubular structure having a first end and a second end, wherein the tubular structure defines a lumen extending from the first end to the second end and defines a central axis extending through the lumen in a longitudinal direction of the tubular structure, and wherein the tubular structure comprises;

a plurality of first members;

a plurality of second members;

wherein the first members and the second members form a braided configuration;

wherein each of the first members comprises;

a first body portion extending in a first helical direction around the central axis;

a first end unjoined portion extending in a second helical direction around the central axis, wherein the second helical direction is opposite of the first helical direction; and

a first end bent portion connecting the body portion to the first end unjoined portion at the first end;

wherein each of the second members comprises;

a first end overlap portion extending alongside the first end unjoined portion of a first member; and

a second body portion extending from the first end overlap portion in the second helical direction around the central axis toward the second end; and

a coating that encapsulates the first end unjoined portions of the first members and the first end overlap portions of the second members.

2. The woven stent of claim 1

wherein each of the first members further comprises:

a second end unjoined portion extending in the second helical direction around the central axis; and

a second end bent portion connecting the first body portion to the second end unjoined portion at the second end;

wherein each of the second members further comprises a second end overlap portion extending from the second body portion and extending alongside the second end unjoined portion of a first member; and

wherein the woven stent further comprises a second end coating that encapsulates the second end unjoined portions of the first members and the second end overlap portions of the second members.

3. The woven stent of claim 1

wherein each of the second members further comprises:

a second end unjoined portion extending in the first helical direction around the central axis; and

a second end bent portion connecting the second body portion to the second end unjoined portion at the second end;

wherein each of the first members further comprises a second end overlap portion extending from the first body portion and extending alongside the second end unjoined portion of a second member; and

wherein the woven stent further comprises a second end coating that encapsulates the second end unjoined portions of the second members and the second end overlap portions of the first members.

4. The woven stent of claim 1 wherein each of the first and second members is selected from the group consisting of a wire and a filament.

5. The woven stent of claim 4 wherein the filament comprises a thermoplastic.

6. The woven stent of claim 1 wherein the coating comprises silicone.

7. The woven stent of claim 1 further comprising a suture woven through at least one cell formed in part by a first end bent portion.

8. The woven stent of claim 1 wherein the plurality of first members comprises 18 wires or 18 filaments and the plurality of second members comprises 18 wires or 18 filaments.

9. The woven stent of claim 1 wherein, in the absence of the coating, each of the first end unjoined portions of the first members is not joined with a corresponding first end overlap portion of a second member.

10. A method for manufacturing a stent, the method comprising:

forming a tubular structure having a first end and a second end, wherein the tubular structure defines a lumen extending from the first end to the second end and defines a central axis extending through the lumen in a longitudinal direction of the tubular structure, and wherein forming the tubular structure comprises;

braiding a plurality of first members with a plurality of second members to form a braided configuration;

bending at least one of the plurality of first members to form a first end bent portion connecting a first body portion arranged to extend in a first helical direction to a first end unjoined portion at the first end;

the first end unjoined portion arranged to extend in a second helical direction around the central axis, wherein the second helical direction is opposite of the first helical direction; and

disposing at least one of the plurality of second members such that the second member includes a first end overlap portion extending alongside the first end unjoined portion of a first member and such that a second body portion extends from the first end overlap portion in the second helical direction around the central axis and toward the second end; and

coating at least a portion of the first end such that the coating encapsulates the first end unjoined portion of the at least one first member and the first end overlap portion of the at least one second member.

11. The method of claim 10 further comprising:

directing laser or ultrasonic energy to heat the first end unjoined portion and the first end overlap portion to a joining temperature for a time sufficient to form a bond upon cooling; and

allowing the first end unjoined portion and the first end overlap portion to cool, thereby forming a bond between the first end unjoined portion and the first end overlap portion;

wherein directing laser or ultrasonic energy and allowing the first end unjoined portion and the first end overlap portion to cool occur before coating at least a portion of the first end.

12. A method for manufacturing a stent, the method comprising:

forming a tubular structure having a first end and a second end, wherein the tubular structure defines a lumen extending from the first end to the second end, and wherein the tubular structure comprises a plurality of first members and a plurality of second members;

contacting a first end unjoined portion of a first member with a first end overlap portion of a second member, wherein the first end overlap portion is parallel to the first end unjoined portion and wherein a line of contact is formed between the first end unjoined portion and the first end overlap portion; and

joining the first end unjoined portion and the first end overlap portion, wherein joining comprises;

directing laser or ultrasonic energy at the line of contact to heat the first end unjoined portion and the first end overlap portion at the line of contact to a joining temperature for a time sufficient to form a bond upon cooling; and

allowing the line of contact to cool, thereby forming a bond between the first end unjoined portion and the first end overlap portion.

13. The method of claim 12 wherein directing laser or ultrasonic energy comprises using a laser.

14. The method of claim 12 wherein at least one of the plurality of first members and one of the plurality of second members comprises a thermoplastic polymer.

15. The method of claim 14 wherein the thermoplastic polymer is polyethylene terephthalate.

16. The method of claim 15 wherein the joining temperature is in a range of from about 255 degrees Celsius to about 353 degrees Celsius.

17. The method of claim 12 wherein the joining temperature is equal to or greater than a melting point of the first end unjoined portion or the first end overlap portion and less than the degradation point of the first end unjoined portion or the first end overlap portion.

18. The method of claim 12 wherein forming the tubular structure comprises braiding a plurality of first members with a plurality of second members on a mandrel.

19. The method of claim 12 wherein each of the first end unjoined portion and the first end overlap portion is a terminal end portion of a first member or second member and the joining of the first end overlap portion and the first end overlap portion forms a closed loop at the first end of the tubular structure.

20. The method of claim 12 further comprising coating at least a portion of the first end such that the coating encapsulates the first end unjoined portions of the first members and the first end overlap portions of the second members.