Methods of automatically regulating operation of ablation members based on determined temperatures

• US 8,961,506 B2
• Filed: 05/09/2014
• Issued: 02/24/2015
• Est. Priority Date: 03/12/2012
• Status: Active Grant

• Current Assignee: Coral Sand Beach, LLC, Advanced Cardiac Therapeutics, Inc. (Medtronic Plc)
• Original Assignee: Advanced Cardiac Therapeutics, Inc. (Medtronic Plc), Meridian Medical Systems LLC
• Inventors: McCarthy, John, Lenihan, Timothy J., Kanowsky, Eric R., Allison, Robert C.
• Primary Examiner(s): MALAMUD, DEBORAH LESLIE
• Application Number:
  US14/274,431
• Publication Number:
  US 20140303610A1
• Time in Patent Office: 291 Days
• Field of Search: 606 20- 21, 606 32- 34, 606 41- 42
• US Class Current: 606/34
• 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 18/082 Probes or electrodes therefor
• CPC Class Codes: A61B 18/12 by passing a current through the tissue to be heated, e.g. high-frequency current
• 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 18/1815 using microwaves
• CPC Class Codes: A61B 2017/0007 Pyrometers
• CPC Class Codes: A61B 2017/00486 Adaptors for coupling parts with incompatible geometries
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00678 upper
• CPC Class Codes: A61B 2018/00708 switching the power on or off
• CPC Class Codes: A61B 2018/00714 Temperature
• CPC Class Codes: A61B 2018/00797 measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00821 measured by a thermocouple
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

Methods and systems for treating tissue that employ a radiometer for temperature measurements and use feedback from the radiometer to regulate energy being applied to the tissue are provided. For example, methods and systems are provided for calculating temperature based on signal(s) from a radiometer, which may provide useful information about tissue temperature at depth, and automatically regulating energy applied to the tissue based on the tissue temperature.

Claims

1. A method of determining a temperature and facilitating ablation of tissue of a subject, comprising:

positioning a catheter of an ablation system at a target anatomical location of a subject;

wherein an integrated catheter tip is positioned along a distal end of the catheter, the integrated catheter tip comprising a radiofrequency electrode, a radiometer and a temperature-measurement device,

wherein the ablation system further comprises a generator for providing energy to the radiofrequency electrode; and

wherein the ablation system further comprises a non-transitory computer-readable medium and a processor;

determining a temperature of a tissue of the subject at a depth relative to a surface of the tissue based on, at least in part, a signal generated by the radiometer, a signal generated by the temperature-measurement device and operation parameters for the radiometer and the temperature-measurement device stored on the computer-readable medium;

delivering radiofrequency energy to the tissue of the subject by activating the generator to provide power to the radiofrequency electrode; and

automatically regulating operation of the radiofrequency electrode based, at least in part, on the determined temperature.

2. The method of claim 1, wherein automatically regulating the operation of the radiofrequency electrode comprises regulating the operation of the radiofrequency electrode to maintain the determined temperature of the tissue within a target temperature setpoint or range.

3. The method of claim 1, further comprising delivering irrigation fluid to a fluid passage of the catheter and through at least one irrigation fluid port positioned at a tip of the catheter to cool tissue adjacent the radiofrequency electrode.

4. The method of claim 1, further comprising monitoring electrical activity of the subject using at least one electrocardiogram electrode, wherein the at least one electrocardiogram electrode is positioned along the integrated catheter tip.

5. The method of claim 1, further comprising operatively coupling the ablation system to an electrophysiology monitoring system.

6. The method of claim 1, wherein positioning the catheter at a target anatomical location of the subject comprises manipulating a steerable catheter or a steerable outer sheath.

7. The method of claim 1, further comprising displaying the determined temperature of tissue on a display of the ablation system.

8. The method of claim 1, wherein the operation parameters for the radiometer comprise a slope and an offset describing a temperature response of the radiometer, and wherein the operation parameters for the temperature-measurement device comprise a slope and an offset describing a temperature response of the temperature-measurement device.

9. A method of determining a temperature and facilitating ablation of tissue of a subject, comprising:

determining a temperature of a tissue of a subject at a depth relative to a surface of the tissue based on, at least in part, a signal generated by a radiometer and a signal generated by a temperature-measurement device, the radiometer and the temperature-measurement device being positioned at a tip of a catheter;

causing energy to be delivered to the tissue of the subject by activating an ablation member positioned at the tip of the catheter; and

automatically regulating operation of the ablation member based, at least in part, on the determined temperature.

10. The method of claim 9, wherein automatically regulating the operation of the ablation member comprises regulating the operation of the ablation member to maintain the determined temperature of the tissue within a target temperature setpoint or range.

11. The method of claim 9, further comprising delivering irrigation fluid to a fluid passage of the catheter and through the at least one irrigation fluid port of the catheter tip to cool tissue adjacent the ablation member.

12. The method of claim 9, further comprising monitoring electrical activity of the subject using at least one electrocardiogram electrode.

13. The method of claim 9, further comprising displaying the determined temperature of tissue on a display.

14. The method of claim 9, wherein the ablation member comprises one of a radiofrequency electrode, a microwave energy ablation member, a cryoablation member and an ultrasound energy ablation member.

15. A method of determining a temperature and facilitating ablation of tissue of a subject, comprising:

determining a temperature of a tissue of a subject at a depth relative to a surface of the tissue based on, at least in part, a signal generated by a radiometer and a signal generated by a temperature-measurement device configured to detect a temperature along a portion of a catheter;

causing energy to be delivered to the tissue of the subject by activating an ablation member positioned along the catheter; and

automatically regulating operation of the ablation member based, at least in part, on the determined temperature.

16. The method of claim 15, wherein automatically regulating the operation of the ablation member comprises regulating the operation of the ablation member to maintain the determined temperature of the tissue within a target temperature setpoint or range.

17. The method of claim 15, further comprising delivering irrigation fluid to a fluid passage of the catheter and through the at least one irrigation fluid port of the catheter to cool tissue adjacent the ablation member.

18. The method of claim 15, further comprising monitoring electrical activity of the subject using at least one electrocardiogram electrode.

19. The method of claim 15, further comprising displaying the determined temperature of tissue on a display.

20. The method of claim 15, wherein the ablation member comprises one of a radiofrequency electrode, a microwave energy ablation member, a cryoablation member and an ultrasound energy ablation member.