Patent ID: 8805500

Claim:
A medical device for stimulating a patient's heart, comprising: a plurality of electrodes; pacing circuitry coupled to the plurality of electrodes to deliver, via the plurality of electrodes, an atrial pacing pulse to an atrial chamber to generate an evoked atrial depolarization and to deliver a stimulation pulse to an atrioventricular node of the heart; and a processor coupled to the pacing circuitry, the processor configured to deliver the stimulation pulse to increase a PR interval of the heart by delivering the stimulation pulse during a stimulation window having a start time corresponding to the delivered atrial pacing pulse so that the stimulation pulse is delivered during a refractory period corresponding to the evoked atrial depolarization, and to deliver a ventricular pacing pulse to a first ventricular chamber during the increased PR interval to cause a contraction of the first ventricular chamber to occur prior to a contraction of a second ventricular chamber to increase dyssynchrony between the contraction of the first ventricular chamber and the contraction of the second ventricular chamber.