Patent ID: 7433736

Claim:
A method comprising: delivering an atrial pacing pulse and a next atrial pacing pulse to a patient, the atrial pacing pulse and the next atrial pacing pulse being separated by an atrial escape interval; tracking ventricular senses following the atrial pacing pulse and the next atrial pacing pulse; determining an expected midpoint of a ventricular sensing window corresponding to a time of a tracked ventricular sense; delivering an atrial test pulse during the atrial escape interval following the atrial pacing pulse and at a predetermined time period prior to the next atrial pacing pulse to evaluate atrial capture; observing a ventricular sense in response to the atrial test pulse; determining a shift in the expected midpoint of the ventricular sensing window in response to the observed ventricular sense, the shift corresponding to a time that occurs between the atrial test pulse and the observed ventricular sense; and determining the ventricular sensing window for the ventricular sense associated with the atrial test pulse based on the determined shift of the expected midpoint.