Intravascular filter membrane with shape memory

• US 20040111111A1
• Filed: 12/10/2002
• Published: 06/10/2004
• Est. Priority Date: 12/10/2002
• Status: Abandoned Application

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Lin, Horng-Ban
• Application Number:
  US10/315,830
• Publication Number:
  US 20040111111A1
• Time in Patent Office: Days
• US Class Current: 606/200
• CPC Class Codes: A61F 2/013 Distal protection devices, i.e. devices placed distally in combination with another endovascular procedure, e.g. angioplasty or stenting
• CPC Class Codes: A61F 2002/018 made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2230/008 paraboloidal
• CPC Class Codes: A61F 2250/0003 having an inflatable pocket filled with fluid, e.g. liquid or gas
• CPC Class Codes: A61M 2025/09183 having tools at the distal tip
• CPC Class Codes: A61M 2205/0266 Shape memory materials
• CPC Class Codes: A61M 25/09 Guide wires

Abstract

An intravascular device can capture embolic debris. An intravascular filter can employ a shape memory filter membrane. In particular, an intravascular filter membrane can be designed for deployment in a vascular system. The filter membrane can be made of a shape memory polymer, and the membrane filter can be moveable between a collapsed insertion configuration and an expanded deployment configuration. The shape memory polymer remembers the expanded deployment configuration.

Claims

1. An intravascular filter membrane for deployment in a vascular system, the filter membrane comprising a shape memory polymer, the membrane moveable between a collapsed insertion configuration and an expanded deployment configuration, wherein the polymer remembers the expanded deployment configuration.

2. The intravascular filter membrane of claim 1, wherein the membrane has a collapsed profile while in its collapsed insertion configuration and a deployed profile in its expanded deployment configuration, and the collapsed profile is smaller than the deployed profile.

3. The intravascular filter membrane of claim 1, wherein the membrane in its collapsed insertion configuration is adapted for insertion via a catheter delivery system.

4. The intravascular filter membrane of claim 1, wherein the membrane in its expanded deployment configuration is adapted to at least substantially occlude a portion of the vascular system in which the intravascular filter membrane is deployed.

5. The intravascular filter membrane of claim 1, wherein the filter membrane has an open proximal end and a closed distal end.

6. The intravascular filter membrane of claim 5, wherein the open proximal end comprises a thickened annular ring adapted to provide an adequate level of hoop strength when the filter membrane is in the deployed configuration.

7. The intravascular filter membrane of claim 1, wherein the shape memory polymer comprises a polymer that remembers a memorized shape when it reaches a temperature that is greater than ambient temperature but is less than or about equal to human body temperature.

8. The intravascular filter membrane of claim 1, wherein the shape memory polymer comprises a polymer that exhibits a large reversible change in its modulus of elasticity at its glass transition temperature.

9. The intravascular filter membrane of claim 1, wherein the shape memory polymer comprise a polymer having a glass transition temperature of less than about 37 degrees C.

10. The intravascular filter membrane of claim 1, wherein the shape memory polymer comprises one of polyurethane, polynorborene, trans-polyisoprene, styrene-butadiene copolymer, or dimethylacrylate-butyl acrylate copolymer.

11. The intravascular filter membrane of claim 10, wherein the shape memory polymer comprises polyurethane.

12. An intravascular filter membrane having an insertion configuration and a deployment configuration, formed by the process of:

providing a polymer membrane comprising a shape memory polymer having a glass transition temperature of less than about 37 degrees C.;

shaping the polymer membrane into the deployment configuration at a temperature at or above about 37 degrees C., thereby locking the deployment configuration into memory;

cooling the polymer membrane to ambient temperature; and

deforming the polymer membrane into the insertion configuration.

13. The intravascular filter membrane of claim 12, wherein the shape memory polymer has a glass transition temperature that is in the range of about 30 to about 35 degrees C.

14. The intravascular filter membrane of claim 12, wherein the polymer membrane is shaped into the deployed configuration at a temperature that is in the range of about 45 to about 60 degrees C.

15. The intravascular filter membrane of claim 12, wherein the insertion configuration of the polymer membrane is adapted for placement within a catheter deployment system.

16. The intravascular filter membrane of claim 12, wherein the insertion configuration is obtained via mechanical deformation of the polymer membrane.

17. The intravascular filter membrane of claim 12, wherein the insertion configuration represents a first memorized shape and the deployment configuration represents a second memorized shape;

where the insertion configuration and the deployment configuration are independently manifested as a result of thermal changes.

18. The intravascular filter membrane of claim 12, wherein the polymer membrane regains a remembered deployment configuration upon subsequent heating to a temperature of about 37 degrees C.

19. The intravascular filter membrane of claim 18, wherein the remembered deployment configuration is substantially identical to the locked in deployment configuration.

20. An intravascular filter assembly comprising:

a frame; and

a filter membrane disposed on the frame, the filter membrane having an insertion configuration and a deployment configuration;

wherein the filter membrane is formed of a shape memory polymer that remembers the deployment configuration and changes from the insertion configuration to the deployment configuration upon heating to about 37 degrees C.

21. The intravascular filter assembly of claim 20, wherein the open end has a first diameter in the insertion configuration and a second diameter in the deployment configuration, the second diameter being greater than the first diameter.

22. The intravascular filter assembly of claim 20, wherein the frame comprises a shape memory material.

23. The intravascular filter assembly of claim 22, wherein the shape memory material comprises a shape memory alloy or a shape memory polymer.

24. The intravascular filter assembly of claim 23, wherein the frame comprises nitinol.

25. The intravascular filter assembly of claim 23, wherein the frame comprises a shape memory polymer and is integrally formed with the filter membrane.

26. A method of forming an intravascular filter membrane that has an insertion configuration and a deployment configuration, the method comprising:

providing a polymer membrane comprising a shape memory polymer having a glass transition temperature of less than about 37 degrees C.;

shaping the polymer membrane into the deployment configuration at a temperature at or above about 37 degrees C., thereby locking the deployment configuration into memory;

cooling the polymer membrane to ambient temperature; and

deforming the polymer membrane into the insertion configuration.

27. The method of claim 26, wherein the shape memory polymer has a glass transition temperature that is in the range of about 30 to about 35 degrees C.

28. The method of claim 26, wherein the polymer membrane is shaped into the deployed configuration at a temperature that is in the range of about 45 to about 60 degrees C.

29. The method of claim 26, wherein the insertion configuration of the polymer membrane is adapted for placement within a catheter deployment system.

30. The method of claim 26, wherein the insertion configuration is obtained via mechanical deformation of the polymer membrane.

31. The method of claim 26, wherein the insertion configuration represents a first memorized shape and the deployment configuration represents a second memorized shape;

where the insertion configuration and the deployment configuration are independently manifested as a result of thermal changes.

32. The method of claim 26, wherein the polymer membrane regains a remembered deployment configuration upon subsequent heating to a temperature of about 37 degrees C.

33. The method of claim 26, wherein the remembered deployment configuration is substantially identical to the locked in deployment configuration.