Pathophysiology of sudden death: electrophysiologic mechanism in different clinical conditions

The onset of life-threatening ventricular tachyarrhythmia or severe bradycardia, asystole or pulseless electrical activity (electromechanical dissociation (EMD)) is the final result of a cascade of events that involves interaction between anatomic and functional substrates and a triggering event that leads to sudden cardiac death (SCD)1,2 (Figure 3.1).