What is the primary characteristic of ventricular tachycardia?

The primary characteristic of ventricular tachycardia is a sustained heart rate of 100 beats per minute or more that occurs with three or more consecutive premature ventricular contractions (PVCs). This arrhythmia originates in the ventricles and reflects a rapid reentrant circuit or a single focus of ectopic ventricular activity. The heart's ventricles contract so quickly that they do not have adequate time to fill, which can severely reduce cardiac output and lead to serious complications.

In this condition, the rapid beating of the ventricles can result in symptoms such as palpitations, dizziness, or even loss of consciousness due to insufficient blood flow to vital organs. The identification of three or more consecutive PVCs as a defining feature emphasizes the reentrant nature of the rhythm, distinguishing it from other less sustained forms of arrhythmia.

The other characteristics mentioned in the other choices do not accurately represent ventricular tachycardia. A heart rate of less than 60 beats per minute indicates bradycardia, intermittent heart rates with occasional PVCs suggest a more benign or different arrhythmic condition, and a rapid heart rate with identifiable P waves indicates atrial activity which is not present in ventricular tachycardia. Thus, the criteria for diagnosing ventricular tachy