Which arrhythmia is characterized by a rapid succession of premature ventricular contractions?

Ventricular tachycardia is characterized by a rapid succession of premature ventricular contractions. This condition typically involves three or more consecutive PVCs occurring at a rate exceeding 100 beats per minute. The underlying mechanism involves reentrant circuits within the ventricles or enhanced automaticity of ventricular myocardial cells.

In this situation, the heart usually does not have adequate time to fill between beats, which can lead to compromised hemodynamics and reduced cardiac output. While ventricular flutter might also involve fast electrical activity originating in the ventricles, it exhibits a different rhythm and is typically more organized than the chaotic nature of premature ventricular contractions that define ventricular tachycardia.

Atrial fibrillation and supraventricular tachycardia originate from the atria or above the ventricles and do not involve a series of consecutive premature ventricular contractions. These arrhythmias have different characteristics and mechanisms that do not align with the definition of rapid, successive PVCs.