Method and device for filtering body fluid

• US 7,371,250 B2
• Filed: 05/03/2005
• Issued: 05/13/2008
• Est. Priority Date: 07/08/1994
• Status: Expired due to Fees

• Current Assignee: ev3, Inc. (Medtronic Plc)
• Original Assignee: ev3, Inc. (Medtronic Plc)
• Inventors: Mazzocchi, Rudy, Claude, Timothy, Segermark, James
• Primary Examiner(s): Bui; Vy Q.
• Application Number:
  US11/120,594
• Publication Number:
  US 20050203571A1
• Time in Patent Office: 1,106 Days
• Field of Search: 606/200, 606191-198, 606/108, 606/159, 623/1.11, 623/1.12
• US Class Current: 606/200
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12099 characterised by the location of the occluder
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12136 Balloons
• CPC Class Codes: A61B 17/12172 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/12177 comprising additional materials, e.g. thrombogenic, having filaments, having fibers or being coated
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2230/0078 hyperboloidal
• CPC Class Codes: A61F 2230/008 paraboloidal
• CPC Class Codes: B21F 45/008 of medical instruments, e.g. stents, corneal rings medical science A61

Abstract

Medical devices for filtering fluids flowing through a lumen and a method of forming medical devices. The devices can be used in vascular channels, urinary tracts, biliary ducts and the like, and filter emboli and other debris generated at a treatment site.

Claims

1. A method for filtering emboli from blood flowing through a body vessel during therapeutic treatment at a treatment site in the vessel comprising:

providing a guidewire having distal and proximal ends and carrying a filter on a distal portion of the guidewire, the filter being expandable from a collapsed delivery configuration to an expanded deployed configuration;

providing a retrieval catheter having a lumen sized to receive the guidewire;

advancing the guidewire through the vessel while the filter is in its collapsed delivery configuration;

expanding the filter to its expanded deployed configuration at a location within the vessel distal to the treatment site;

introducing the distal end of a treatment catheter into the vessel, the treatment catheter having a lumen sized to receive the guidewire;

advancing the treatment catheter over the guidewire to the treatment site;

performing a therapeutic treatment at the treatment site with die treatment catheter;

filtering emboli released into blood during the therapeutic treatment with the filter;

removing the treatment catheter from the vessel;

after the treatment catheter has been removed introducing the distal end of the retrieval catheter into the vessel;

advancing the retrieval catheter over the guidewire to retrieve the filter; and

removing the retrieval catheter, guidewire and filter from the vessel.

2. The method of claim 1 wherein the distal end of the treatment catheter is introduced into the vessel after the filter is expanded.

3. The method of claim 1 wherein the treatment site is a stenosis and wherein the step of performing a therapeutic treatment comprises urging the stenosis radially outwardly to squeeze the stenosis against a wall of the vessel.

4. The method of claim 1 wherein at least a portion of the filter is self-expanding.

5. The method of claim 1 wherein the filter has proximal and distal ends and wherein the distal end of the filter is connected to a distal band which encircles the guidewire.

6. The method of claim 5 wherein the distal band is connected in a fixed position on the guidewire.

7. The method of claim 1 wherein the filter has proximal and distal ends and wherein the proximal end of the filter is connected to a tube which encircles the guidewire.

8. The method of claim 7 wherein the tube is slidably disposed about the guidewire.

9. The method of claim 1 wherein the filter comprises a metal.

10. The method of claim 9 wherein the metal comprises nitinol.

11. The method of claim 1 wherein the filter is fixed to the guidewire.

12. The method of claim 1 further comprising providing an introduction catheter which covers the filter and wherein expanding the filter comprises advancing the filter distally beyond a distal end of the introduction catheter.

13. The method of claim 1 wherein the distal end of the treatment catheter is introduced into the vessel after the filter is expanded, and wherein the treatment site is a stenosis and wherein the step of performing a therapeutic treatment comprises urging the stenosis radially outwardly to squeeze the stenosis against a wall of the vessel.

14. The method of claim 1 wherein the filter comprises a filter mesh.

15. The method of claim 14 wherein the filter mesh comprises a metal.

16. The method of claim 15 wherein the metal comprises nitinol.

17. A method of protecting a patient from embolization during therapeutic treatment at a treatment site within a vessel, comprising:

introducing the distal end of a guidewire into the vessel;

advancing the guidewire through the vessel to position a distal end of the guidewire downstream of the treatment site;

introducing the distal end of a treatment catheter into the vessel, the treatment catheter having a lumen sized to receive the guidewire;

advancing the treatment catheter over the guidewire to position the treatment catheter at the treatment site within the vessel;

performing a therapeutic treatment at the treatment site with the treatment catheter;

preventing movement of emboli released into the blood during the therapeutic treatment distally beyond the distal end of the guidewire;

removing the treatment catheter from the vessel while the emboli remain in the vessel;

after the treatment catheter has been removed introducing the distal end of a retrieval catheter into the vessel;

advancing the retrieval catheter over the guidewire to retrieve the emboli; and

removing the retrieval catheter, guidewire, and emboli from the vessel.

18. The method of claim 17 wherein preventing movement of emboli comprises capturing the emboli at a location between the treatment site and the distal end of the guidewire.

19. The method of claim 18 wherein an intravascular device is carried adjacent a distal end of the guidewire and wherein the method further comprises advancing the intravascular device through the vessel to a location distal to the treatment site.

20. The method of claim 19 wherein the intravascular device is a filter and wherein capturing the emboli comprises engaging the emboli with the filter.

21. The method of claim 20 wherein the filter comprises a metal.

22. The method of claim 21 wherein the metal comprises nitinol.

23. The method of claim 20 wherein the filter includes a filter mesh.

24. The method of claim 20 further comprising expanding the filter within the vessel and wherein the filter is expanded before the treatment catheter is advanced over the guidewire.

25. The method of claim 20 further comprising expanding the filter within the vessel and wherein the filter is expanded before the treatment catheter is introduced into the vessel.

26. The method of claim 20 wherein at least a portion of the filter is self-expanding.

27. The method of claim 20 wherein the filter has proximal and distal ends and wherein the distal end of the filter is connected to a distal band which encircles the guidewire.

28. The method of claim 27 wherein the distal band is connected in a fixed position on the guidewire.

29. The method of claim 20 wherein the filter has proximal and distal ends and wherein the proximal end of the filter is connected to a tube which encircles the guidewire.

30. The method of claim 29 wherein the tube is slidably disposed about the guidewire.

31. The method of claim 20 wherein the filter is fixed to the guidewire.

32. The method of claim 23 wherein capturing emboli comprises engaging the emboli with the filter mesh.

33. The method of claim 23 wherein the filter mesh comprises a metal.

34. The method of claim 33 wherein the metal comprises nitinol.