Tissue Oxygenation Monitoring in Heart Failure

• US 20100318146A1
• Filed: 06/10/2010
• Published: 12/16/2010
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Kuhn, Jonathan L., Cinbis, Can, Anderson, David A., Carney, James K.
• Granted Patent: US 10,179,242 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/36557 controlled by chemical substances in blood

Abstract

A medical device for monitoring delivery of a therapy that includes a therapy delivery module to deliver a therapy, a controller to set a therapy delivery control parameter, an optical sensor to produce a signal corresponding to tissue light attenuation, and a processor configured to compute a tissue oxygenation measurement from the optical sensor signal, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation.

Claims

1. A medical device for monitoring delivery of a therapy, comprising:

a therapy delivery module to deliver a therapy;

a controller to set a therapy delivery control parameter;

an optical sensor to sense a signal corresponding to tissue light attenuation; and

a processor configured to compute a tissue oxygenation measurement from the optical sensor signal, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation.

2. The device of claim 1, wherein the optical sensor comprises a light emitting portion emitting at least four spaced apart wavelengths and a light detecting portion producing a signal corresponding to the tissue light attenuation at the at least four spaced apart wavelengths.

3. The device of claim 2, wherein the processor computes a second derivative of the tissue light attenuation with respect to wavelength and computes an absolute tissue oxygen saturation using the second derivative.

4. The device of claim 3, further comprising computing a total hemoglobin volume fraction using the absolute tissue oxygen saturation.

5. The device of claim 4, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to one of a maximum tissue oxygen saturation and a maximum total hemoglobin volume fraction.

6. The device of claim 4, wherein the processor computes a tissue oxygenation index using the tissue oxygen saturation and the total hemoglobin volume fraction and the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation index.

7. The device of claim 1, wherein the optical sensor is an external sensor emitting light transcutaneously.

8. The device of claim 1, wherein the optical sensor is an implantable sensor.

9. The device of claim 8, further comprising a sealed housing, wherein the optical sensor is configured within the sealed housing.

10. The device of claim 8, further comprising an electrical lead electrically coupled to the medical device, the lead comprising an elongated lead body, wherein the optical sensor is positioned along the elongated lead body.

11. The device of claim 8, further comprising a medical device telemetry module, wherein the optical sensor comprises:

a sealed housing; and

a sensor telemetry module configured for bidirectional communication with the medical device telemetry module.

12. The device of claim 1, wherein the optical sensor comprises a light detecting portion and a light emitting portion, one of the light detecting portion and the light emitting portion being an implantable portion and the other of the light detecting portion and the light emitting portion being an external portion positioned in facing opposition with the implantable portion.

13. The device of claim 1, further comprising:

a plurality of electrodes to stimulate at least one heart chamber;

a pulse generator to deliver pacing pulses to the at least one heart chamber via the plurality of electrodes, wherein the control parameter corresponds to a parameter for controlling cardiac resynchronization therapy.

14. The device of claim 12, wherein the control parameter comprises one of an electrode location, a timing parameter and an electrode selection parameter.

15. The device of claim 1, further comprising:

a catheter; and

a fluid delivery module.

16. The device of claim 1, further comprising:

a plurality of electrodes; and

a pulse generator to deliver stimulation pulses to a nerve via the plurality of pacing pulses.

17. The device of claim 1, wherein the medical device comprises a cardiac assist device for delivering the therapy.

18. A method for monitoring delivery of a therapy in a medical device, comprising;

delivering a therapy using a plurality of settings of a therapy delivery control parameter;

sensing an optical sensor signal corresponding to tissue light attenuation;

computing tissue oxygenation measurement from the optical sensor signal; and

determining a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation.

19. The method of claim 18, wherein delivering the therapy comprises delivering pacing pulses to at least one heart chamber.

20. The method of claim 19, wherein the control parameter comprises one of an electrode location, a timing parameter and an electrode selection parameter.

21. The method of claim 18, wherein delivering the therapy comprises delivering a heart failure medication.

22. The method of claim 18, wherein delivering the therapy comprises delivering stimulation pulses to a nerve.

23. The method of claim 18, wherein delivering the therapy comprises delivering a cardiac assist therapy.

24. A computer readable medium having computer executable instructions for performing a method comprising:

delivering a therapy using a plurality of settings of a therapy delivery control parameter;

sensing an optical sensor signal corresponding to tissue light attenuation;

computing tissue oxygenation measurement from the optical sensor signal; and

determining a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation.