Home > Heart Disease > Sudden Cardiac Arrest Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Jul 20, 2008 by CMachell, Views: 5175 Sudden cardiac arrest occurs when the lower chambers of the heart suddenly stop beating normally and develop what is called ventricular fibrillation. Ventricular fibrillation is a very fast, chaotic heart rate in the lower chambers of the heart. Ventricular fibrillation quickly becomes more erratic, resulting in sudden cardiac arrest. If this is not corrected immediately via a shock from an external defibrillator or an implantable cardioverter defibrillator, death will follow.