Automatic baroreflex modulation based on cardiac activity

• US 8,000,793 B2
• Filed: 05/23/2008
• Issued: 08/16/2011
• Est. Priority Date: 12/24/2003
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Libbus, Imad
• Primary Examiner(s): Layno; Carl H
• Assistant Examiner(s): Stice; Paula J
• Application Number:
  US12/126,182
• Publication Number:
  US 20080228238A1
• Time in Patent Office: 1,180 Days
• Field of Search: 607/9, 607 17- 20, 607/44
• US Class Current: 607/44
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/4047 afferent nerves, i.e. nerves that relay impulses to the central nervous system
• CPC Class Codes: A61N 1/3611 Respiration control stimulating respiratory organs A61N1/3601
• CPC Class Codes: A61N 1/36117 for treating hypertension
• CPC Class Codes: A61N 1/36139 with automatic adjustment

Abstract

An aspect relates to a system for providing baroreflex stimulation. An embodiment of the system comprises a cardiac activity monitor to sense cardiac activity and provide a signal indicative of the cardiac activity, and a baroreflex stimulator. The stimulator includes a pulse generator and a modulator. The pulse generator provides a baroreflex stimulation signal adapted to provide a baroreflex therapy. The modulator receives the signal indicative of the cardiac activity and modulates the baroreflex stimulation signal based on the signal indicative of the cardiac activity to change the baroreflex therapy from a first baroreflex therapy to a second baroreflex therapy.

Claims

1. A method for operating an implantable medical device, comprising:

receiving a signal indicative of sensed activity, wherein receiving a signal indicative of sensed activity includes communicating with another implantable medical device, wherein the other implantable medical device is an implantable cardiac stimulator configured to sense activity;

automatically classifying the sensed activity as an activity level selected from at least two defined activity levels preprogrammed in the implantable medical device;

automatically selecting a baroreflex stimulation level based on the activity level of the detected activity, wherein the baroreflex stimulation level is selected from at least two defined baroreflex stimulation levels preprogrammed in the implantable medical device; and

automatically delivering a baroreflex therapy using the baroreflex stimulation level.

2. The method of claim 1, wherein the at least two defined activity levels preprogrammed into the implantable medical device includes rest and exercise, automatically classifying the detected activity includes automatically classifying the detected activity as rest or exercise, and automatically delivering a baroreflex therapy includes automatically applying baroreflex stimulation during rest and automatically withdrawing baroreflex stimulation during exercise.

3. The method of claim 1, wherein the at least two defined activity levels preprogrammed into the implantable medical device includes a first activity level and a second activity level where the first activity level is higher than the second activity level, automatically classifying the detected activity includes automatically classifying the detected activity as the first activity level or the second activity level, and automatically selecting a baroreflex stimulation level includes automatically selecting a first baroreflex stimulation level when the activity level is determined to be the second activity level and automatically selecting a second baroreflex stimulation level when the activity level is determined to be the first activity level, wherein the first baroreflex stimulation level is higher than the second baroreflex stimulation level.

4. The method of claim 1, wherein the defined baroreflex stimulation levels preprogrammed in the implantable medical device have an inverse relationship with the defined activity levels preprogrammed in the implantable medical device such that an incremental increase in the activity level corresponds with an incremental decrease in the baroreflex stimulation level.

5. The method of claim 1, wherein receiving a signal indicative of sensed activity further includes sensing a heart rate using the implantable medical device.

6. The method of claim 1, wherein the implantable cardiac stimulator is configured to sense cardiac activity and acquire heart rate data, and wherein receiving a signal indicative of sensed activity includes receiving the heart rate data from the implantable cardiac stimulator.

7. The method of claim 1, wherein receiving a signal indicative of sensed activity further includes sensing respiration using the implantable medical device.

8. The method of claim 7, wherein sensing respiration includes sensing tidal volume.

9. The method of claim 7, wherein sensing respiration includes sensing minute ventilation.

10. The method of claim 1, wherein the implantable cardiac stimulator is configured to sense respiration and acquire respiration data, and wherein receiving a signal indicative of sensed activity includes receiving the respiration data from the implantable cardiac stimulator.

11. The method of claim 1, wherein receiving a signal indicative of sensed activity further includes sensing acceleration using the implantable medical device.

12. The method of claim 1, wherein the implantable cardiac stimulator is configured to sense acceleration and acquire acceleration data, and wherein receiving a signal indicative of sensed activity includes receiving the acceleration data from the implantable cardiac stimulator.

13. The method of claim 1, wherein the sensed activity includes a combination of at least two of heart rate, minute ventilation or acceleration.

14. The method of claim 1, further comprising delivering baroreflex stimulation through a lead adapted to be fed through a right ventricle and pulmonary valve into a pulmonary artery.

15. The method of claim 14, further comprising targeting sensory nerve endings sensitive to pressure within the pulmonary artery and avoiding stimulation of other neural pathways to stimulate a desired response while reducing undesired effects of stimulation.

16. A method for operating an implantable medical device, comprising:

receiving a signal indicative of sensed activity, wherein receiving a signal indicative of sensed activity includes communicating with another implantable medical device, wherein the other implantable medical device is an implantable cardiac stimulator configured to sense activity, and wherein the sensed activity includes a signal indicative of sensed heart rate, sensed respiration or sensed acceleration;

automatically classifying the sensed activity as an activity level selected from at least two defined activity levels preprogrammed in the implantable medical device, wherein the at least two defined activity levels preprogrammed into the implantable medical device includes rest and exercise, wherein automatically classifying the detected activity includes automatically classifying the detected activity as rest or exercise;

automatically selecting a baroreflex stimulation level based on the activity level of the detected activity, wherein the baroreflex stimulation level is selected from at least two defined baroreflex stimulation levels preprogrammed in the implantable medical device; and

automatically delivering a baroreflex therapy using the baroreflex stimulation level, wherein automatically delivering a baroreflex therapy includes automatically applying baroreflex stimulation during rest and automatically withdrawing baroreflex stimulation during exercise.

17. The method of claim 16, wherein the sensed activity includes sensed respiration, and the sensed respiration includes tidal volume or minute ventilation.

18. A method for operating an implantable medical device, comprising:

receiving a signal indicative of sensed activity, wherein receiving a signal indicative of sensed activity includes communicating with another implantable medical device, wherein the other implantable medical device is an implantable cardiac stimulator configured to sense activity;

automatically classifying the sensed activity as an activity level selected from at least two defined activity levels preprogrammed in the implantable medical device, wherein the at least two defined activity levels preprogrammed into the implantable medical device includes a first activity level and a second activity level where the first activity level is higher than the second activity level, wherein automatically classifying the detected activity includes automatically classifying the detected activity as the first activity level or the second activity level;

automatically selecting a baroreflex stimulation level based on the activity level of the detected activity, wherein the baroreflex stimulation level is selected from at least two defined baroreflex stimulation levels preprogrammed in the implantable medical device, wherein automatically selecting a baroreflex stimulation level includes automatically selecting a first baroreflex stimulation level when the activity level is determined to be the second activity level and automatically selecting a second baroreflex stimulation level when the activity level is determined to be the first activity level, wherein the first baroreflex stimulation level is higher than the second baroreflex stimulation level; and

automatically delivering a baroreflex therapy using the baroreflex stimulation level, wherein the defined baroreflex stimulation levels preprogrammed in the implantable medical device have an inverse relationship with the defined activity levels preprogrammed in the implantable medical device such that an incremental increase in the activity level corresponds with an incremental decrease in the baroreflex stimulation level.

19. The method of claim 18, wherein the signal indicative of sensed activity includes a signal indicative of heart rate, respiration or acceleration.

20. The method of claim 19, wherein the signal indicative of sensed activity includes a signal indicative of at least two of heart rate, respiration or acceleration.