What is Post Ventricular Atrial Refractory Period (PVARP)

Post-Ventricular Atrial Refractory Period (PVARP):

•PVARP is a programmable period after a ventricular paced or sensed event in which sensed atrial events do not initiate timing cycles or inhibit atrial pacing. PVARP may prevent the tracking of retrograde atrial events initiated in the ventricle that could trigger PMT in a dual chamber device programmed to a tracking mode.

•The initial section of PVARP is the cross-chamber blanking period (composed of absolute refractory and noise window) followed by the fixed refractory period

•Events that fall into the absolute refractory window of cross-chamber blanking are not sensed or marked

•Events that fall into the noise window are marked as [AS]; there is no noise window for SMART blanking

•Events in fixed refractory are marked as (AS), (AF), or (PAC)

•Although sensed events in the PVARP fixed refractory window do not initiate timing cycles, they do count toward ATR Entry Counts, AFR, and are included in counters/histograms

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