Method and system for dynamic atrioventricular delay with adaptive search and rate-responsive search extension

Abstract

An implantable medical device (IMD) and process are provided comprising one or more electrodes configured to be implanted to define a pacing vector through at least a portion of a ventricle. Sensing circuitry is configured to sense intrinsic atrial activity (As) and intrinsic ventricular activity (Vs). A pulse generator (PG) if provided, and memory configured to store program instructions and an atrioventricular delay search parameter (AVD). The AVDis an interval of time. One or more processors, that when executing the program instructions, is configured to direct the PG to deliver ventricular pacing pulses based on an atrioventricular delay (AVD) and periodically initiate an AVD search operation utilizing the AVD. A heart rate is determined and compared to a threshold. Responsive to determining that the heart rate exceeds the threshold, the AVDis reduced, and cardiac activity is detected during the AVD search operation utilizing the reduced AVD.