Patent ID: 6871096

Claim:
In a multi-site, cardiac pacing system for delivering ventricular pacing pulses, a method of timing the delivery of left ventricular pacing pulses from a preceding atrial event and following, in time, the depolarization of the right ventricle comprising: establishing a left ventricular atrial-ventricular delay (A-LVp) from an atrial event (A) to time the delivery of a left ventricular pacing pulse (LVp) by: sensing ventricular depolarizations of the left ventricle as a left ventricular sense (LVs) event; measuring the intrinsic atrial-left ventricular delay between an atrial event and the LVs event as an intrinsic A-LVs delay; sensing ventricular depolarizations of the right ventricle as a right ventricular sense (RVs) event; measuring the intrinsic atrial-right ventricular delay between an atrial event and the RVs event as an intrinsic A-RVs delay; and determining an A-LVp delay that is shorter than the intrinsic A-LVs delay and longer than the intrinsic A-RVs delay; starting an A-LVp delay timer from an atrial event (A); and delivering a left ventricular pacing pulse to the left ventricle when the A-LVp delay timer reaches the determined A-LVp delay to effect fusion pacing of the left ventricle with intrinsic depolarization of the right ventricle.