Patent ID: 8321017

Claim:
For use with an implantable system, a method for monitoring a patient's electromechanical delay (EMD) and arterial blood pressure, the method comprising: (a) causing paced cardiac events by delivering sufficient pacing stimulation to cause capture to the patient's heart; (b) using one or more electrodes implanted within and/or on the patient's heart to obtain a cardiogenic impedance (CI) signal indicative of cardiac contractile activity while the patient's heart is being paced at step (a); (c) using an implanted sensor or implanted electrodes, remote from the patient's heart, to obtain a plethysmography signal indicative of changes in arterial blood volume remote from the patient's heart while the patient's heart is being paced at step (a); (d) detecting one or more predetermined features of the CI signal obtained at step (b); (e) detecting one or more predetermined features of the plethysmography signal obtained at step (c); (f) determining a value indicative of the patient's electromechanical delay (EMD) by determining a time between a pacing stimulation delivered at step (a) and at least one of the one or more predetermined features of the CI signal detected at step (d); (g) determining a metric indicative of pulse arrival time (PAT) by determining a time between a pacing stimulation delivered at step (a) and at least one of the one or more predetermined features of the plethysmography signal detected at step (e), minus the determined value indicative of EMD; and (h) estimating the patient's arterial blood pressure based on the metric indicative of PAT determined at step (g); wherein at least one of steps (f), (g) and (h) is/are performed using at least one processor.