"For most people who have a sudden cardiac arrest, it is too late for them by the time 911 is called," said the study's senior author, Sumeet Chugh, MD, director of the Heart Rhythm Center at the Cedars-Sinai Heart Institute in Los Angeles. "Because so few survive, it's crucial for us to predict which patients are most vulnerable. This new risk score gives us a better idea of who is most likely to have cardiac arrest. Best of all, it is broadly accessible. It uses widely available and very inexpensive technology."