Cardiac Electrophysiology Practice Test

When the ventricles are driven by an escape rhythm due to a block in the atrioventricular conduction, the pace comes from a distal pacemaker in the His-Purkinje system. That ventricular escape rhythm is intrinsically slow, typically around the low 30s to 40 beats per minute. So the ventricular rate in this scenario is usually about 30–40 bpm. This is slower than normal sinus rhythm (60–100 bpm) and slower than a junctional escape rhythm (40–60 bpm), which would occur if the block were at the AV node rather than below it.