Which rhythm is described as a lethal arrhythmia indicating extreme myocardial irritability?

• A. Ventricular Tachycardia
• B. Atrial Fibrillation
• C. Ventricular Fibrillation
• D. Asystole

Answer: (A)

Extreme ventricular irritability leads to a rhythm where the ventricles lose any coordinated contraction. Ventricular fibrillation embodies this precisely: the ECG shows rapid, chaotic, irregular activity with no identifiable P waves or QRS complexes, and there is no effective pulse. It is instantly life-threatening and requires immediate defibrillation and CPR. While ventricular tachycardia can also be dangerous, it is a fast but organized rhythm that may still produce some cardiac output if a pulse is present, and it does not reflect the same level of chaotic instability seen in VF. Atrial fibrillation is an atrial rhythm with an irregularly irregular ventricular response and is not the classic sign of extreme ventricular irritability. Asystole is no electrical activity at all and, again, represents a different, non-irritable state.