Sudden cardiac arrest (SCA), the leading cause of death in USA and Europe, is the condition in which the heart is no longer able to pump blood to the brain and other organs, because of an electrical problem resulting in a fatal arrhythmia in heart. Most of the time, heart becomes chaotic (ventricular fibrillation, VF) or rapid (ventricular tachycardia, VT). When this happens, blood stops flowing to the brain and the rest of the body, and the person collapses. In fact, the victim is clinically dead and will remain so unless someone helps immediately. When someone collapses from SCA, immediate defibrillation and cardiopulmonary resuscitation (CPR) are essential for any chance of recovery.