Smart delay for intermittent stress therapy

1. A method for delivering pacing pulses, comprising:

sensing intrinsic atrioventricular (AV) intervals;

using the intrinsic AV interval and a predetermined equation relating the AV interval to a calculated optimal AV delay to provide a maximum positive rate of left ventricular pressure change during systole; and

calculating an AV delay using a predetermined percentage of the calculated optimal AV delay to deliver ventricular pacing pulses, wherein the predetermined percentage is less than 100%, to provide a desired level of stress by introducing or augmenting dyssynchrony for cardiac protective pacing therapy (CPPT) to provide a cardiac conditioning therapy to improve autonomic balance.

2. The method of claim 1 , further comprising:

receiving LV electrode location; and

calculating the AV delay using the LV electrode location.

3. The method of claim 1 , further comprising:

sensing intrinsic interventricular (VV) interval; and

calculating the AV delay using the sensed intrinsic VV interval.

4. The method of claim 1 , further comprising:

sensing QRS width; and

calculating the AV delay using the sensed QRS width.

5. The method of claim 4 , wherein calculating the AV delay includes calculating a first AV delay for a wide QRS width and a second AV delay for a narrow QRS width.

6. The method of claim 5 , wherein a wide QRS width includes QRS width greater than approximately 150 msec.

7. The method of claim 5 , wherein a narrow QRS width includes QRS width greater than approximately 120 msec and less then approximately 150 msec.

8. The method of claim 1 , further comprising:

sensing heart rate (HR) in response to the pacing sequences;

dynamically adjusting parameters of the AV delay for the CPPT based on the sensed HR.

9. A method for operating a cardiac pacing device, comprising:

delivering cardiac protective pacing therapy (CPPT) to provide a cardiac conditioning therapy to improve autonomic balance to one or more ventricular sites in an atrial tracking pacing mode with an atrioventricular (AV) delay;

sensing intrinsic AV intervals;

modulating the AV delay based on the sensed intrinsic AV intervals, including calculating AV delay using the intrinsic AV interval and a predetermined equation relating the AV interval to a calculated optimal AV delay, and using a predetermined percentage of the calculated optimal AV delay to deliver ventricular pacing pulses to provide a desired level of stress by introducing or augmenting dyssynchrony for the CPPT, wherein the predetermined percentage is less than 100%;

sensing heart rate (HR) in response to the pacing pulses; and

dynamically adjusting parameters of the AV delay for the pacing pulses based on the sensed HR in a closed loop system.

10. The method of claim 9 , further comprising:

receiving LV electrode location; and

modulating the AV delay using the LV electrode location.

11. The method of claim 9 , further comprising:

sensing intrinsic interventricular (VV) interval; and

modulating the AV delay using the sensed intrinsic VV interval.

12. The method of claim 9 , further comprising:

sensing QRS width; and

modulating the AV delay using the sensed QRS width.

13. The method of claim 9 , wherein modulating AV delay includes using a short AV delay to provide a first selected amount of stress during cardioprotective pacing.

14. The method of claim 13 , wherein using a short AV delay includes using an AV delay that is 10 to 20 percent of the intrinsic AV interval.

15. The method of claim 13 , wherein modulating AV delay includes using a long AV delay to provide a second selected amount of stress during cardioprotective pacing, wherein the second amount is greater than the first amount.

16. The method of claim 15 , wherein using a long AV delay includes using an AV delay that is 80 to 95 percent of the intrinsic AV interval.

17. The method of claim 15 , wherein modulating AV delay includes using an AV delay and a VV delay to provide a third selected amount of stress during cardioprotective pacing, wherein the third amount is greater than the second amount.

18. A system, comprising:

a signal input to receive at least one cardiac signal indicative of cardiac events including at least one atrial event and one ventricular event;

an event detector, coupled to the signal input, to detect the at least one atrial event and one ventricular event;

a measurement module, coupled to the event detector, to measure an atrioventricular (AV) time interval between an atrial event and a ventricular event; and

an AV delay calculator coupled to the measurement module, the AV delay calculator adapted to calculate an AV delay using the AV interval and a predetermined equation relating the AV interval to a calculated optimal AV delay to provide a maximum positive rate of left ventricular pressure change during systole, and further adapted to calculate a percentage of the calculated optimal AV delay to deliver ventricular pacing pulses to provide a desired level of stress by introducing or augmenting dyssynchrony for cardiac protective pacing therapy (CPPT) to provide a cardiac conditioning therapy to improve autonomic balance, wherein the percentage is less than 100%.

19. The system of claim 18 , further comprising an input for sensing intrinsic interventricular timing.

20. The system of claim 18 , further comprising an input for receiving left ventricular (LV) lead location.

21. The system of claim 18 , further comprising an input for sensing QRS width.

22. The system of claim 18 , further comprising an input for sensing heart rate (HR).