Cardioversion is the delivery of energy that is

Cardioversion is the delivery of energy that is

• A. Synchronized
• B. Unsynchronized
• C. Randomized
• D. Delayed

Answer: (A)

Cardioversion delivers energy in synchrony with the heart’s electrical cycle, timed to the QRS complex so the shock coincides with ventricular depolarization. This keeps the timing safe for organized tachyarrhythmias, landing the shock when the ventricles are ready to respond and avoiding delivery during the vulnerable period around repolarization, which could trigger ventricular fibrillation. The alternative of an unsynchronized (random) shock is used for defibrillation in chaotic rhythms, not for cardioversion; the other terms don’t describe this rhythm-timed delivery.

Cardioversion delivers energy in synchrony with the heart’s electrical cycle, timed to the QRS complex so the shock coincides with ventricular depolarization. This keeps the timing safe for organized tachyarrhythmias, landing the shock when the ventricles are ready to respond and avoiding delivery during the vulnerable period around repolarization, which could trigger ventricular fibrillation. The alternative of an unsynchronized (random) shock is used for defibrillation in chaotic rhythms, not for cardioversion; the other terms don’t describe this rhythm-timed delivery.