12/04/2026
Cardioversion is a medical procedure designed to restore a normal heart rhythm in patients with certain arrhythmias. Unlike defibrillation, which delivers unsynchronized shocks during cardiac arrest, cardioversion uses carefully timed electrical energy to reset the heart’s rhythm.
The electrical shock is synchronized with the R wave of the ECG to avoid the vulnerable phase of the T wave, where an untimely shock could trigger dangerous rhythms such as ventricular fibrillation.
Cardioversion typically uses lower energy levels than defibrillation and is considered for tachyarrhythmias such as supraventricular tachycardia, atrial flutter, atrial fibrillation, or stable ventricular tachycardia with a pulse. It is indicated when arrhythmias cause symptoms like hypotension, chest pain, pulmonary congestion, or reduced consciousness.
