Patent ID: 8923963

Claim:
A leadless cardiac device comprising a signal generator module configured to deliver pacing pulses to an atrium; a processing module configured to: detect a ventricular activation event, determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event, schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval, and control the signal generator module to deliver the pacing pulse at the scheduled time; a housing configured for implantation within the atrium, wherein the housing encloses the signal generator and the processing module; and a memory that stores a baseline atrioventricular (AV) value that is an expected value of the interval between the ventricular activation event and the previous atrial event during normal AV conduction of the heart; wherein the processing module is configured to: compare the determined length of the interval to the baseline AV value, and schedule the time at which to deliver the pacing pulse to the atrium in order to maintain a baseline atrial pacing rate based on the comparison, and wherein the processing module is configured to continue to compare the stored baseline atrioventricular (AV) value, unchanged, to subsequent intervals.