Ventricular tachycardia with two variable foci.

Torsades de pointes results from a ventricular tachycardia with two variable foci, and when considered in detail, can be differentiated from patterns of bulging of ventricular fibrillation. Episodes of bulging electrical activity seen during complete His bundle block are therefore not due to ventricular fibrillation, although they can degenerate into ventricular fibrillation. The existence of a spontaneously reversible ventricular fibrillation in normothermic conditions in humans can only be established with concurrent synchronized recordings.