Over 424,000 sudden cardiac arrests occur each year, according to the Sudden Cardiac Foundation. Sudden cardiac arrest (SCA) occurs when a person becomes unconscious with no pulse and no breathing. This can happen to anyone, anywhere. This person is clinically dead.
But according to the American Heart Association, rescuers who know cardiopulmonary resuscitation and use an automated external defibrillator (AED) can increase the chance of survival to 50 to 74 percent.