Temperature controlled short duration ablation

• US 10,405,920 B2
• Filed: 06/10/2016
• Issued: 09/10/2019
• Est. Priority Date: 01/25/2016
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Govari, Assaf, Ephrath, Yaron, Altmann, Andres Claudio, Zilberman, Israel
• Primary Examiner(s): Cohen, Lee S
• Assistant Examiner(s): Demie, Tigist S
• Application Number:
  US15/179,090
• Publication Number:
  US 20170209208A1
• Time in Patent Office: 1,187 Days
• CPC Class Codes: A61B 18/1206 Generators therefor
• 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 2018/00351 Heart
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00648 using more than one sensed parameter
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00678 upper
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00708 switching the power on or off
• CPC Class Codes: A61B 2018/00714 Temperature
• CPC Class Codes: A61B 2018/00738 Depth, e.g. depth of ablation
• CPC Class Codes: A61B 2018/00744 Fluid flow
• CPC Class Codes: A61B 2018/00779 Power or energy
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00797 measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/00886 Duration
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 2217/007 : with irrigation system
• CPC Class Codes: A61B 2218/002 : Irrigation

Abstract

A method, including selecting a first maximum radiofrequency (RF) power to be delivered by an electrode within a range of 70W-100W, and selecting a second maximum RF power to be delivered by the electrode within a range of 20W-60W. The method also includes selecting an allowable force on the electrode within a range of 5 g-50 g, selecting a maximum allowable temperature, of tissue to be ablated, within a range of 55° C.-65° C., and selecting an irrigation rate for providing irrigation fluid to the electrode within a range of 8-45 ml/min. The method further includes performing an ablation of tissue using the selected values by initially using the first power, switching to the second power after a predefined time between 3 s and 6 s, and terminating the ablation after a total time for the ablation between 10 s and 20 s.

Claims

1. A method, comprising:

selecting a maximum radiofrequency (RF) power to be delivered by an electrode within a range of 70 W-100 W;

selecting an allowable force on the electrode within a range of 5 g-50 g;

selecting a maximum allowable temperature, of tissue to be ablated, within a range of 55°

C.-65°

C.;

selecting an irrigation rate for providing irrigation fluid to the electrode within a range of 8-30 ml/min; and

performing an ablation of the tissue using the selected values for a time period between 1 s and 6 s.

2. The method according to claim 1, wherein the selected values are:

maximum RF power 90 W, allowable force between 10 g and 20 g, maximum allowable temperature 60°

C., and irrigation rate 15 ml/min, and wherein the power is delivered for 3 s so as to provide a lesion having a depth between 1 mm and 3 mm.

3. The method according to claim 1, wherein the selected values are:

maximum RF power 90 W, allowable force between 10 g and 20 g, maximum allowable temperature 60°

C., and irrigation rate 15 ml/min, and wherein the power is delivered for 3 s, and is then reduced to 50 W so as to provide a lesion having a depth between 4 mm and 5 mm.

4. The method according to claim 1, and comprising measuring an impedance to an RF power delivered by the electrode during the ablation, and, when a change in the impedance exceeds a preset value, halting the ablation of the tissue.

5. The method according to claim 4, wherein the change is at least 7Ω

.

6. The method according to claim 1, and comprising measuring at respective times a temperature of the tissue, and, when the temperature exceeds the selected maximum allowable temperature, reducing a level of an RF power delivered by the electrode.

7. The method according to claim 6, wherein the temperature of the tissue is measured at a frequency of at least 30 Hz.

8. Apparatus, comprising:

an electrode;

a power control module configured to select a maximum radiofrequency (RF) power to be delivered by the electrode within a range of 70 W-100 W; and

a processor coupled to the power control module and configured to;

select an allowable force on the electrode within a range of 5 g-50 g;

select a maximum allowable temperature, of tissue to be ablated, within a range of 55°

C.-65°

C.;

select an irrigation rate for providing irrigation fluid to the electrode within a range of 8-30 ml/min; and

perform an ablation of the tissue using the selected values for a time period between 1 s and 6 s.

9. The apparatus according to claim 8, wherein the selected values are:

maximum RF power 90 W, allowable force between 10 g and 20 g, maximum allowable temperature 60°

C., and irrigation rate 15 ml/min, and wherein the power is delivered for 3 s so as to provide a lesion having a depth between 1 mm and 3 mm.

10. The apparatus according to claim 8, wherein the selected values are:

maximum RF power 90 W, allowable force between 10 g and 20 g, maximum allowable temperature 60°

C., and irrigation rate 15 ml/min, and wherein the power is delivered for 3 s, and is then reduced to 50 W so as to provide a lesion having a depth between 4 mm and 5 mm.

11. The apparatus according to claim 8, wherein the processor is configured to measure an impedance to an RF power delivered by the electrode during the ablation, and, when a change in the impedance exceeds a preset value, halt the ablation of the tissue.

12. The apparatus according to claim 11, wherein the change is at least 7Ω

.

13. The apparatus according to claim 8, wherein the processor is configured to measure at respective times a temperature of the tissue, and, when the temperature exceeds the selected maximum allowable temperature, to reducing a level of an RF power delivered by the electrode.

14. The apparatus according to claim 13, wherein the temperature of the tissue is measured at a frequency of at least 30 Hz.