Cardioversion is the term used when a procedure is performed to convert a person’s heart rhythm to normal sinus rhythm from an arrhythmia. This can be done either chemically using antiarrhythmic drugs or electrically. Atrial fibrillation is the most common arrhythmia requiring cardioversion, however atrial flutter, atrial tachycardia, ventricular tachycardia and ventricular fibrillation also respond to cardioversion.

Electrical cardioversion requires anesthesia. Defibrillator pads are placed on the chest and a shock is delivered. Using an anterior-posterior approach has been shown to allow energy reduction compared to an anterior-apical approach.

Automated external defibrillators (AEDs) are widely available and are designed to be used by non-medical bystanders during out-of-hospital cardiac arrest.