Every year EMS treats nearly 300,000 victims of out-of-hospital cardiac arrest (when the heart suddenly stops beating) each year in the US. Less than eight percent of people who suffer cardiac arrest outside the hospital survive. Effective bystander CPR, provided immediately after sudden cardiac arrest, can double or triple a victim’s chance of survival; however, less than one-third of out-of-hospital sudden cardiac arrest victims receive bystander CPR.

Even if CPR is performed, defibrillation with an Automated External Defibrillator (AED) is required to stop the abnormal rhythm and restore a normal heart rhythm. New technology has made AEDs simple and user-friendly. Clear audio and visual cues tell users what to do when using an AED and coach people through CPR. A shock is delivered only if the victim needs it.

Source: AHA, CPR & Sudden Cardiac Arrest (SCA) Fact Sheet, April 26, 2010.