Method of forming a nitinol stent

Patent metadata

Field	Value
Publication number	US-9345596-B2
Application number	US-201213403784-A
Country	US
Kind code	B2
Filing date	Feb 23, 2012
Priority date	Feb 23, 2012
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A method of a forming a hollow, drug-eluting nitinol stent includes shaping a composite wire into a stent pattern, wherein the composite wire comprises an inner member, a nitinol intermediate member, and an outer member. After the composite wire is shaped into the stent pattern, the composite wire is heat treated to set the nitinol intermediate member in the stent pattern. After heat treatment, the composite wire is processed to remove the outer member and the inner member without adversely affecting the intermediate member. Openings may be provided through the intermediate member and the lumen of the intermediate member may be filled with a substance to be eluted through the openings.

First claim

What is claimed is:

1. A method of forming a stent comprising the steps of:
shaping a composite wire into a stent pattern, wherein the composite wire comprises an inner member, an intermediate member, and an outer member, wherein the intermediate member is a nitinol material;
heat treating the composite wire in the stent pattern;
after the heat treating step, processing the composite wire such that the outer member is removed from around the intermediate member without adversely affecting the intermediate member.

2. The method of claim 1 , further comprising the step of, after the heat treating step, processing the composite wire such that the inner member is removed from the intermediate member without adversely affecting the intermediate member.

3. The method of claim 2 , further comprising the step of filling a lumen of the intermediate member with a biologically or pharmacologically active substance after the inner member is removed.

4. The method of claim 3 , wherein the substance is selected from the group consisting of antineoplastic, antimitotic, antiinflammatory, antiplatelet, anticoagulant, anti fibrin, antithrombin, antiproliferative, antibiotic, antioxidant, and antiallergic substances as well as combinations thereof.

5. The method of claim 3 , further comprising the step of providing openings through the intermediate member to the lumen of the intermediate member.

6. The method of claim 5 , wherein the step of providing openings through the intermediate member comprises laser drilling openings through the intermediate member.

7. The method of claim 2 , wherein the outer member and the inner member comprise tantalum or molybdenum, and wherein the step of processing the composite wire to remove the outer member and the step of processing the composite wire to remove the inner member comprises exposing the composite wire to xenon difluoride gas.

8. The method of claim 1 , wherein the outer member comprises a material selected from the group consisting of tantalum and molybdenum, and wherein the step of processing the composite wire to remove the outer member comprises exposing the composite wire to xenon difluoride gas or hydrofluoric acid.

9. A method of forming a stent comprising the steps of:
shaping a composite wire into a stent pattern, wherein the composite wire comprises an inner member, an intermediate member, and an outer member, wherein the intermediate member is a nitinol material;
heat treating the composite wire in the stent pattern;
after the heat treating step, processing the composite wire such that the outer member is removed from around the intermediate member without adversely affecting the intermediate member;
providing openings through the intermediate member to a lumen of the intermediate member; and
after the heat treating step, processing the composite wire such that the inner member is removed from the intermediate member without adversely affecting the intermediate member.

10. The method of claim 9 , wherein the step of providing openings through the intermediate member comprises providing openings through the outer member and the intermediate member, and wherein the steps processing the composite wire such that the outer member is removed and such that the inner member is removed are performed in a single step.

11. The method of claim 9 , further comprising the step of filling the lumen of the intermediate member with a biologically or pharmacologically active substance after the inner member has been removed.

12. The method of claim 9 , wherein the substance is selected from the group consisting of antineoplastic, antimitotic, antiinflammatory, antiplatelet, anticoagulant, anti fibrin, antithrombin, antiproliferative, antibiotic, antioxidant, and antiallergic substances as well as combinations thereof.

Assignees

• Thompson Dustin M
• Medtronic Vascular Inc

Inventors

• Thompson Dustin M

Classifications

• B21F45/00

  Wire-working in the manufacture of other particular articles (of pins, needles, nails, hairpins B21G; of chains B21L) · CPC title

• A61F2/915

  with bands having a meander structure, adjacent bands being connected to each other · CPC title

• A61L2300/416

  Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus · CPC title

• A61F2210/0014

  using shape memory or superelastic materials, e.g. nitinol · CPC title

• A61L31/088

  Other specific inorganic materials not covered by A61L31/084 or A61L31/086 · CPC title