Multipolarity epicardial radiofrequency ablation

• US 9,044,245 B2
• Filed: 01/05/2011
• Issued: 06/02/2015
• Est. Priority Date: 01/05/2011
• Status: Active Grant

• Current Assignee: Medtronic Ablation Frontiers LLC (Medtronic Plc)
• Original Assignee: Medtronic Ablation Frontiers LLC (Medtronic Plc)
• Inventors: Condie, Catherine R., Ahlberg, Sarah E.
• Primary Examiner(s): Stoklosa, Joseph
• Assistant Examiner(s): Ram, Jocelyn D
• Application Number:
  US12/984,675
• Publication Number:
  US 20120172859A1
• Time in Patent Office: 1,609 Days
• Field of Search: 606/32, 606/41
• US Class Current: 1/1
• 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 2018/00029 open
• CPC Class Codes: A61B 2018/00267 having a basket shaped structure
• CPC Class Codes: A61B 2018/00363 Epicardium
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00821 measured by a thermocouple
• CPC Class Codes: A61B 2018/1407 Loop
• CPC Class Codes: A61B 2018/1467 using more than two electrodes on a single probe
• CPC Class Codes: A61B 2218/002 Irrigation

Abstract

A method of ablating an epicardial tissue region, including positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located in between the first and second electrodes; delivering an irrigation fluid to the tissue region; and ablating at least a portion of the tissue region by sequentially activating the third electrode in a monopolar radiofrequency delivery mode and activating the first and second electrodes in a bipolar radiofrequency delivery mode.

Claims

1. A method of treating a tissue region, comprising:

positioning a first, second, and third electrode in proximity to the tissue region, the second and third electrodes positioned on opposite sides of and adjacent to the first electrode;

ablating a first portion of the tissue region by conducting an electrical current between the first electrode and a ground electrode spaced from the tissue region; and

then ablating a second portion of the tissue region by conducting an electrical current between the second electrode and the third electrode around the first portion of the tissue region.

2. The method of claim 1, wherein the first, second, and third electrodes are arranged in a substantially arcuate configuration on a medical device.

3. The method of claim 1, further comprising delivering a radiofrequency signal from a radiofrequency signal generator to the first electrode.

4. The method of claim 3, further comprising measuring a temperature of at least one of the first, second, and third electrodes.

5. The method of claim 4, further comprising modifying the delivery of the radiofrequency signal based at least in part on the measured temperature.

6. The method of claim 1, wherein the tissue region includes an epicardial surface of a heart.

7. The method of claim 1, wherein the tissue region includes a septal wall.

8. A method of ablating an epicardial tissue region, comprising:

positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located substantially between the first and second electrodes;

ablating a first portion of the tissue region by conducting a radiofrequency signal between the third electrode and a return electrode located away from the epicardial tissue region; and

then ablating a second portion of the tissue region by conducting a radiofrequency signal between the first and second electrodes and around the first portion of the tissue region.

9. The method of claim 8, wherein positioning the medical device includes routing at least a portion of the medical device through a sub-xiphoid incision.

10. The method of claim 8, wherein positioning the medical device includes routing at least a portion of the medical device through a thoracotomy incision.

11. The method of claim 8, further comprising re-positioning the medical device and operating the first, second, and third electrodes to create a plurality of ablative lesions.

12. The method of claim 8, wherein the first, second, and third electrodes are arranged in a substantially arcuate configuration on a medical device.

13. The method of claim 8, further comprising measuring a temperature of at least one of the first, second, and third electrodes.

14. The method of claim 13, further comprising modifying the radiofrequency signal based at least in part on the measured temperature.

15. The method of claim 8, further comprising irrigating at least a portion of the first, second, and third electrodes.

16. A method of ablating an epicardial tissue region, comprising:

positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located in between the first and second electrodes, each of the first electrode, second electrode, and third electrode being at least partially encapsulated by a sheath;

circulating an irrigation fluid within the sheath of each of the first electrode, second electrode, and third electrode; and

ablating a first portion of the tissue region by activating the third electrode in a monopolar radiofrequency delivery mode and then ablating a second portion of the tissue region by activating the first and second electrodes in a bipolar radiofrequency delivery mode.

17. The method of claim 16, further comprising measuring an electrical activity of the epicardial tissue region.