Home > Heart Disease > Ventricular Fibrillation Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Jul 20, 2008 by AArshad, Views: 6940 Ventricular fibrillation (VF) is a very fast, chaotic heart rate in the lower chambers of the heart. Ventricular fibrillation can occur spontaneously (generally caused by heart disease) or when ventricular tachycardia has persisted too long. The instant ventricular fibrillation begins, effective blood pumping stops. Ventricular fibrillation quickly becomes more erratic, resulting in sudden cardiac arrest.