Catheter with cryogenic and electrical heating ablation

• US 7,951,140 B2
• Filed: 01/09/2008
• Issued: 05/31/2011
• Est. Priority Date: 12/09/1999
• Status: Expired due to Fees

• Current Assignee: Medtronic CryoCath LP (Medtronic Plc)
• Original Assignee: Medtronic CryoCath LP (Medtronic Plc)
• Inventors: Carroll, Sean, Wittenberger, Dan, Abboud, Marwan, Arless, Steven G., Milder, Fredric L.
• Primary Examiner(s): Dvorak; Linda C
• Assistant Examiner(s): SCOTT, AMANDA L
• Application Number:
  US11/971,582
• Publication Number:
  US 20080114345A1
• Time in Patent Office: 1,238 Days
• Field of Search: 606 20- 26
• US Class Current: 606/21
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2018/0212 using an instrument inserted into a body lumen, e.g. catheter
• CPC Class Codes: A61B 2018/0268 with restriction of flow

Abstract

A catheter includes a cryoablation tip with an electrically-driven ablation assembly for heating tissue. The cryoablation tip may be implemented with a cooling chamber through which a controllably injected coolant circulates to lower the tip temperature, and having an RF electrode at its distal end. The RF electrode may be operated to warm cryogenically-cooled tissue, or the coolant may be controlled to conductively cool the tissue in coordination with an RF treatment regimen, allowing greater versatility of operation and enhancing the lesion size, speed or placement of multi-lesion treatment or single lesion re-treatment cycles.

Claims

1. A catheter for the treatment of tissue having a controller, comprising:

a catheter body,

a treatment tip positioned on the catheter body, the tip having a cryogenic cooling segment for contacting and thermally treating tissue, and an electrically-driven ablation assembly, the electrically-driven ablation assembly operable by the controller to apply heating ablation energy to the tissue and ablate the tissue simultaneously with the cooling segment.

2. The catheter of claim 1, wherein the cooling segment operates to ablate the contacted tissue to a predetermined cooled tissue boundary and the electrically-driven ablation assembly operates to extend ablation beyond the predetermined cooled tissue boundary.

3. The catheter of claim 1, wherein the tip further comprises one or more sensing electrodes, the sensing electrodes usable to cold-map cardiac tissue sites.

4. The catheter of claim 1, wherein the electrically driven ablation assembly and the cooling segment are arranged to provide a predetermined tip temperature.

5. The catheter of claim 1, wherein the cooling segment is coolable to about −

70°

C.

6. The catheter of claim 1, wherein the electrically-driven ablation assembly includes an electrode assembly for applying radio frequency energy.

7. The catheter of claim 6, further comprising a driver providing the radio frequency energy at a frequency effective to achieve enhanced absorption in the thermally treated tissue at a depth beyond a thermal conduction depth of the cooling segment.

8. The catheter of claim 1, wherein the electrically-driven ablation assembly and the cooling segment operate to prevent near field charring during ablation.

9. The catheter of claim 1, wherein the electrically-driven ablation assembly and the cooling segment operate to prevent near field icing during ablation.

10. The catheter of claim 1, wherein the electrically-driven ablation assembly and the cooling segment operate to maintain a non-ablating near field temperature while attaining an ablation temperature at a depth beyond a thermal conduction depth of the cooling segment.

11. A catheter for the treatment of tissue, comprising:

a catheter body,

a treatment tip positioned on the catheter body, the tip having a cryogenic cooling segment for contacting and thermally treating tissue, and an electrically-driven ablation assembly, the electrically-driven ablation assembly operable to apply heating ablation energy to the tissue, the cooling segment ablates contacted tissue to a predetermined cooled tissue boundary and the electrically-driven ablation assembly extends ablation beyond the predetermined cooled tissue boundary.

12. The catheter of claim 11, wherein the tip further comprises one or more sensing electrodes, the sensing electrodes usable to cold-map cardiac tissue sites.

13. The catheter of claim 11, wherein the electrically driven ablation assembly and the cooling segment operate simultaneously to provide a predetermined tip temperature.

14. The catheter of claim 11, wherein the cooling segment is coolable to about −

70°

C.

15. The catheter of claim 11, wherein the electrically-driven ablation assembly includes an electrode assembly for applying radio frequency energy.

16. The catheter of claim 15, further comprising a driver providing the radio frequency energy at a frequency effective to achieve enhanced absorption in the thermally treated tissue at a depth beyond a thermal conduction depth of the cooling segment.

17. The catheter of claim 11, wherein the electrically-driven ablation assembly and the cooling segment operate to prevent near field charring during ablation.

18. The catheter of claim 11, wherein the electrically-driven ablation assembly and the cooling segment operate to prevent near field icing during ablation.

19. The catheter of claim 11, wherein the electrically-driven ablation assembly and the cooling segment operate to maintain a non-ablating near field temperature while attaining an ablation temperature at a depth beyond a thermal conduction depth of the cooling segment.