Pacemaker AV Interval vs PV Interval

Pacemaker AV interval vs PV interval

AV interval indicates the paced atrioventricular interval and PV interval indicates sensed atrioventricular interval. This means that the ‘A’ of AV interval stands for the Atrial paced signal and ‘P’ of PV interval stands for the spontaneous P wave which is sensed by the pacemaker. The ventricular stimulus is given by the pacemaker at the end of the programmed AV or PV interval.

Hence AV interval would mean A pace/V pace and PV interval would indicate A sense/V pace. AV interval is usually programmed longer than PV interval by about 20 ms. This is because it takes some time after the onset of spontaneous atrial activity before it is detected by the pacemaker. In case of atrial pacing, the pacemaker knows exactly when the atrial stimulus was given and does not have to sense it!