Patent ID: 8050760

Claim:
A method for use with an implantable medical device for implant within a patient, the method comprising: detecting a plurality of cardiogenic impedance signals along different sensing vectors within the patient; detecting a measure of mechanical dyssynchrony in the heart of the patient based on a comparison of the cardiogenic impedance signals, including detecting abnormally contracting segments, if any, within the heart of the patient; and controlling at least one device function based on the measure of mechanical dyssynchrony; wherein detecting the measure of mechanical dyssynchrony includes delivering a pacing pulse to the heart of the patient; for each of the cardiogenic impedance signals, examining the signal to detect a maximum in a first time derivative of the signal after pulse delivery and then measuring the time delay from the pulse to the maximum in the first time derivative; and comparing the peak velocity delay times derived from the cardiogenic impedance signals to generate the measure of mechanical dyssynchrony.