Overview

Ventricular fibrillation is a type of abnormal heart rhythm (arrhythmia). During ventricular fibrillation, disorganized heart signals cause the lower heart chambers (ventricles) to twitch (quiver) uselessly. As a result, the heart doesn't pump blood to the rest of the body.

Ventricular fibrillation is an emergency that requires immediate medical attention. It's the most frequent cause of sudden cardiac death.

Emergency treatment for ventricular fibrillation includes cardiopulmonary resuscitation (CPR) and shocks to the heart with a device called an automated external defibrillator (AED). Medications, implanted devices or surgery may be recommended to prevent episodes of ventricular fibrillation.