Patent ID: 7181284

Claim:
A method of bi-ventricular, fusion-pacing therapy delivery to a non-synchronous pair of ventricles, including delivery of a single ventricular pre-excitation pacing pulse to a relatively late activated ventricular chamber to promote mechanical synchrony between the late activated ventricular chamber and a relatively more rapid, intrinsically conducting ventricular chamber, comprising: measuring an intrinsic atrio-ventricular delay interval for a first-to-depolarize ventricular (V 1 ) chamber for at least two prior cardiac cycles; and delivering during a subsequent cardiac cycle at least one ventricular pre-excitation pacing pulse to a second-to-depolarize ventricular (V 2 ) chamber, wherein said at least one ventricular pre-excitation pacing pulse is delivered at the expiration of a V 2 pacing interval, wherein the V 2 pacing interval is temporally shorter than an A-V 1 delay interval derived from the measured intrinsic atrio-ventricular delay intervals of the V 1 chamber.