RATE SMOOTHING CONTROL

• US 20070233201A1
• Filed: 06/07/2007
• Published: 10/04/2007
• Est. Priority Date: 05/26/2000
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Schwartz, Mark, Lovett, Eric
• Granted Patent: US 8,512,220 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36564 controlled by blood pressure

Abstract

A rate smoothing function used in implantable pulse generators uses detected triggering events, which cause the rate smoothing function to be activated or deactivated, and detected parameter adjusting events, which cause parameter(s) of the rate smoothing function to be changed. In one example, the activation/deactivation and/or change to the parameters of the rate smoothing function are temporary, and the pre-event state of the rate smoothing function is set to a post-adjusting state, such as after a first time interval. Rate smoothing may be selected, activated or deactivated, or adjusted based on a cardiac signal state, or based on an activity or other physiological sensor signal. The adjusted rate smoothing parameters may include an up-smoothing percentage to limit a speed of pacing rate increase and a down-smoothing percentage to limit a speed of pacing rate drop.

Claims

1. A cardiac pacing system, comprising:

a sensor configured to monitor a physiologic parameter other than intrinsic electrical cardiac depolarizations; and

a pacing rate controller circuit including a rate smoothing module coupled to the sensor to receive the physiologic parameter, the rate smoothing module configured to perform, using the physiologic parameter, at least one of activating rate smoothing, deactivating rate smoothing, and adjusting one or more rate smoothing parameters.

2. The system of claim 1, wherein the sensor is configured to provide an indication of a metabolic need for a heart rate.

3. The system of claim 2, wherein the sensor comprises an accelerometer.

4. The system of claim 2, wherein the sensor comprises a respiration sensor.

5. The system of claim 1, wherein the sensor is configured to monitor a cardiac function.

6. The system of claim 5, wherein the sensor comprises a pressure sensor.

7. The system of claim 5, wherein the sensor comprises a cardiac contractility sensor.

8. The system of claim 1, wherein the rate smoothing module is configured to limit a speed of pacing rate increase using a first rate smoothing percentage.

9. The system of claim 8, wherein the rate smoothing module is configured to limit a speed of pacing rate drop using a second rate smoothing percentage.

10. The system of claim 9, wherein the rate smoothing module is configured to adjust the first rate smoothing percentage and the second rate smoothing percentage in response to a parameter adjusting event detected from the physiologic parameter.

11. The system of claim 10, wherein the rate smoothing module is configured to calculate the first rate smoothing percentage and the second rate smoothing percentage using the physiologic parameter.

12. The system of claim 11, wherein the rate smoothing module is configured to activate or deactivate rate smoothing in response to a triggering event detected from the physiologic parameter.

13. A method for cardiac pacing using an implantable system, the method comprising:

monitoring a physiologic parameter other than intrinsic electrical cardiac depolarizations using a sensor of the implantable system; and

adjusting a first rate smoothing percentage and a second rate smoothing percentage in response to a parameter adjusting event detected from the physiologic parameter using a control circuit of the implantable system, the first rate smoothing percentage limiting a speed of pacing rate increase, the second rate smoothing percentage limiting a speed of pacing rate drop.

14. The method of claim 13, comprising calculating the first rate smoothing percentage and second rate smoothing percentage using the physiologic parameter.

15. The method of claim 13, further comprising calculating a pacing rate using the physiologic parameter.

16. The method of claim 13, further comprising providing cardiac resynchronization therapy.

17. The method of claim 13, wherein monitoring the physiologic parameter comprises monitoring metabolic need.

18. The method of claim 17, wherein monitoring the physiologic parameter comprises monitoring the physiologic parameter using an accelerometer.

19. The method of claim 17, wherein monitoring the physiologic parameter comprises monitoring the physiologic parameter using a respiratory sensor.

20. The method of claim 13, wherein monitoring the physiologic parameter comprises monitoring heart function.

21. The method of claim 20, wherein monitoring the physiologic parameter comprises monitoring the physiologic parameter using a blood pressure sensor.

22. The method of claim 20, wherein monitoring the physiologic parameter comprises monitoring the physiologic parameter using a cardiac contractility sensor.

23. The method of claim 13, comprising activating or deactivating rate smoothing in response to a triggering event detected from the physiologic parameter using the control circuit of the implantable system.