Ventricular escape beat

Animation illustrating the normal activation of the electrical conduction system of the heart: starting from the sinoatrial node, an electrical impulse spreads across the atria, then passes through the atrioventricular node (AV node) and conducts on via the bundle branches towards the ventricles.

In cardiology, a ventricular escape beat is a self-generated electrical discharge initiated by, and causing contraction of the ventricles of the heart; normally the heart rhythm is begun in the atria of the heart and is subsequently transmitted to the ventricles. The ventricular escape beat follows a long pause in ventricular rhythm and acts to prevent cardiac arrest. It indicates a failure of the electrical conduction system of the heart to stimulate the ventricles (which would lead to the absence of heartbeats, unless ventricular escape beats occur).