Patent ID: 7930029

Claim:
A method of operating an implantable cardiac device to characterize a cardiac response to pacing, comprising: delivering a plurality of captured pacing pulses to a heart chamber that capture the heart chamber; sensing a captured cardiac signal following delivery of each captured pacing pulse, each captured cardiac signal associated with a captured pacing response; measuring a captured peak amplitude value and a captured peak timing value of each captured cardiac signal; determining a median value of the captured peak timing values; determining a captured peak threshold from the measured captured peak amplitude values; delivering a plurality of non-captured pacing pulses to the heart chamber that do not capture the heart chamber; sensing a non-captured cardiac signal following delivery of each non-captured pacing pulse, each non-captured cardiac signal associated with a non-captured pacing response; measuring a non-captured peak amplitude value for each non-captured cardiac signal; determining a non-captured peak threshold from the measured non-captured peak amplitude values; comparing a peak timing of a cardiac signal of a subsequent paced cardiac cycle to the median value of the captured peak timing values; comparing a peak amplitude of the cardiac signal of the subsequent paced cardiac cycle to the captured peak amplitude threshold and the noncaptured peak amplitude threshold; determining the cardiac response to pacing of the heart chamber for the subsequent paced cardiac cycle based on comparing the peak timing of the cardiac signal to the median value of the captured peak timing values and comparing the peak amplitude of the cardiac signal to the captured peak amplitude threshold and the non-captured peak amplitude threshold; and providing pacing therapy according to the cardiac pacing response determination.