Patent ID: 7555336

Claim:
A method of monitoring ventricular capture in a ventricular cardiac resynchronization therapy (CRT) delivery device to promote mechanical synchrony between ventricular chambers, comprising: suspending a CRT delivery regimen; verifying an absence of possibly deleterious cardiac rhythms, and after successfully verifying the absence of possibly deleterious cardiac rhythms; conducting a ventricular conduction test to a first ventricle, wherein the first ventricle receives pacing stimulation; and monitoring a second ventricle during a period of time following, wherein said second ventricle is free of direct pacing stimulation, for inter-ventricular conduction of said pacing stimulation from said first ventricle; and wherein the ventricular conduction test comprises: extending a cardiac pacing atrio-ventricular (AV) interval measuring a PR time interval, said PR interval defined as the time elapsed between a sensed or paced atrial event (A-event) and an antegrade-conducted right ventricular sense (RVs) event, or, in the event that a ventricular pace occurs upon the expiration of the extended AV interval, assuming the presence of some degree of AV block and between said A-event and the ventricular pace; and programming one of a relatively short AV interval and a minimum AV interval as the test AV interval.