Perfusion filter catheter

• US 6,361,545 B1
• Filed: 09/22/1998
• Issued: 03/26/2002
• Est. Priority Date: 09/26/1997
• Status: Expired due to Term

• Current Assignee: Surgerx Medical, LLC
• Original Assignee: Cardeon Corporation
• Inventors: Macoviak, John A., Leary, James J., Samson, Wilfred J.
• Primary Examiner(s): Reip, David O.
• Assistant Examiner(s): Woo, Julian W.
• Application Number:
  US09/158,405
• Time in Patent Office: 1,281 Days
• Field of Search: 606/191, 606/192, 606/194, 606/198, 606/200, 606/113, 606/151, 606/114, 604/265
• 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 17/12109 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 17/221 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 2017/22067 Blocking; Occlusion A61B2017/22054 takes precedence
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• 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 2/014 Retrograde blood flow filters, i.e. device inserted against the blood flow direction
• CPC Class Codes: A61F 2002/018 made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2210/0033 electrically, e.g. heated by resistor
• 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 2230/008 paraboloidal
• CPC Class Codes: A61F 2250/0003 having an inflatable pocket filled with fluid, e.g. liquid or gas
• CPC Class Codes: A61F 2250/0023 differing in porosity
• CPC Class Codes: A61F 2250/0098 : radio-opaque, e.g. radio-opaque markers

Abstract

A perfusion filter catheter is used to capture potential emboli within the aorta during heart surgery and cardiopulmonary bypass. An expandable embolic filter assembly having fine filter mesh for capturing macroemboli and microemboli is mounted on a catheter shaft having a perfusion lumen with perfusion ports located upstream of the filter. The embolic filter assembly can be actively or passively deployed within the ascending aortic. An optional outer tube covers the embolic filter assembly to prevent premature deployment. Radiopaque markers, sonoreflective markers and/or an aortic transillumination system are provided to monitor the position of the catheter and the deployment state of the embolic filter assembly. The embolic filter assembly is configured to maximize the effective filter surface area when deployed. Embolic filter assembly configurations described include an elongated cone, a frustum of a cone, a trumpet-shape, a modified trumpet-shape, and helically, circumferentially and longitudinally convoluted shapes, as well as configurations having standoff members for centering the filter and holding the filter mesh away from the aortic walls when deployed. Oxygenated blood is perfused through the perfusion lumen and any embolic materials that might be dislodged are captured in the deployed embolic filter assembly. Embodiments are also described that combine the perfusion filter catheter with an aortic occlusion device, which may be a toroidal balloon, an expandable balloon or a selectively deployable external catheter flow control valve. The combined device allows percutaneous transluminal administration of cardiopulmonary bypass and cardioplegic arrest with protection from undesirable embolic events.

Claims

1. A perfusion filter catheter comprising:

an elongated catheter shaft,

an embolic filter assembly having a porous filter mesh mounted on said catheter shaft, said embolic filter assembly being expandable to engage an inner surface of a patient'"'"'s aorta, said embolic filter assembly including a plurality of standoff members spaced apart from and surrounding said filter mesh for holding said filter mesh away from an inner wall of the aorta when said embolic filter assembly is in an expanded state.

2. The perfusion filter catheter of claim 1, wherein said embolic filter assembly is configured to expand passively in response to blood flow in the aorta.

3. The perfusion filter catheter of claim 1, wherein said embolic filter assembly is resiliently biased toward the expanded state.

4. The perfusion filter catheter of claim 1, wherein said embolic filter assembly includes a means to actively expand said embolic filter assembly within the aorta.

5. The perfusion filter catheter of claim 4, wherein said means to actively expand said embolic filter assembly comprises a plurality of actuation members connected to an outer periphery of said embolic filter assembly.

6. The perfusion filter catheter of claim 5 wherein said actuation members comprise a plurality of actuation wires slidably received within at least one actuation wire lumen within said elongated catheter shaft, said actuation wires having distal ends connected to the outer periphery of said embolic filter assembly.

7. The perfusion filter catheter of claim 1, wherein said embolic filter assembly has an outer periphery and said elongated catheter shaft is approximately tangential to said outer periphery of said embolic filter assembly when said embolic filter assembly is in the expanded state.

8. The perfusion filter catheter of claim 1 wherein said filter mesh comprises a plurality of regions having different pore sizes.

9. The perfusion filter catheter of claim 1 wherein said standoff members comprise a plurality of longitudinally oriented wire standoff members.

10. The perfusion filter catheter of claim 1 wherein said embolic filter assembly is configured with a conical upstream section and an approximately cylindrical extension extending downstream of said conical upstream section.

11. The perfusion filter catheter of claim 1 further comprising a perfusion lumen within said elongated catheter shaft, said perfusion lumen being fluidly connected to a perfusion port on said elongated catheter shaft upstream of said filter mesh.

12. A perfusion filter catheter comprising:

an elongated catheter shaft,

an embolic filter assembly having a porous filter mesh mounted on said catheter shaft, said embolic filter assembly being expandable to engage an inner surface of a patient'"'"'s aorta, said embolic filter assembly including a cage spaced apart from and surrounding said filter mesh for holding said filter mesh away from an inner wall of the aorta when said embolic filter assembly is in an expanded state.

13. The perfusion filter catheter of claim 12, further comprising a perfusion lumen within said elongated catheter shaft, said perfusion lumen being fluidly connected to a perfusion port on said elongated catheter shaft upstream of said filter mesh.

14. The perfusion filter catheter of claim 12, wherein said embolic filter assembly is configured with a conical upstream section and an approximately cylindrical extension extending downstream of said conical upstream section.

15. The perfusion filter catheter of claim 12, wherein said filter mesh includes a first pore size configured to capture microemboli and a second pore size configured to capture macroemboli.

16. The perfusion filter catheter of claim 15, wherein said first pore size is in the range of 1 to 100 micrometers and said second pore is in the range of 50 to 200 micrometers.

17. A perfusion filter catheter comprising:

an elongated catheter shaft,

an embolic filter assembly having a porous filter mesh mounted on said catheter shaft, said embolic filter assembly being expandable to engage an inner surface of a patient'"'"'s aorta, said embolic filter assembly including a plurality of standoff members for holding said filter mesh away from an inner wall of the aorta when said embolic filter assembly is in an expanded state, said plurality of standoff members forming a generally cylindrical assembly.

18. The perfusion filter catheter of claim 17, wherein said plurality of standoff members comprise a plurality of longitudinally oriented wires.

19. The perfusion filter catheter of claim 17, wherein said plurality of standoff members comprise a plurality of coiled wire standoff members surrounding said filter mesh.

20. The perfusion filter catheter of claim 17, wherein said plurality of standoff members are constructed of a resilient polymer.

21. The perfusion filter catheter of claim 17, wherein said plurality of standoff members arc constructed of an elastic metal alloy.

22. The perfusion filter catheter of claim 17, wherein said plurality of standoff members are constructed of a superelastic metal alloy.

23. The perfusion filter catheter of claim 17, wherein said plurality of standoff members are constructed of a shape-memory material.

24. A perfusion filter catheter comprising:

an elongated catheter shaft,

an embolic filter assembly having a porous filter mesh mounted on said catheter shaft, said embolic filter assembly being expandable to engage an inner surface of a patient'"'"'s aorta, said embolic filter assembly including a generally cylindrical cage surrounding said filter mesh for holding said filter mesh away from an inner wall of the aorta when said embolic filter assembly is in an expanded state.

25. The perfusion filter catheter of claim 24, wherein said cage comprises a course netting surrounding said filter mesh.