Patent ID: 8428716

Claim:
A method of left ventricular pacing including automated adjustment of a atrio-ventricular (AV) pacing delay interval and intrinsic AV nodal conduction testing comprising—upon expiration or reset of a programmable AV Evaluation Interval (AVEI) between occurrences of conduction testing—performing the following steps: temporarily increasing a paced AV (PAV) interval and a sensed AV (SAV) interval and testing for AV conduction and measuring a median intrinsic atrio-ventricular (PR) interval for a first-to-depolarize ventricular chamber for at least three consecutive cardiac cycles; storing the median PR interval in a memory structure; subtracting from the median PR interval to define a pre-excitation interval (PEI); delivering a pacing stimulus to the last to depolarize ventricle approximately at the expiration of the PEI; and in the event that the AV conduction test reveals conduction block then: 1. performing a pacing mode-switch to a bi-ventricular (Bi-V) pacing mode and 2. increasing the magnitude of the AVEI.