Many medical dramas on TV or in the movies feature defibrillation or “shock” paddles when someone is in the midst of a cardiac arrest. Similarly, an implantable cardioverter defibrillator, or ICD, is an electronic device that constantly monitors your heart rhythm. It delivers energy to the heart muscle once it detects a very fast, abnormal rhythm.

In this white board session, Walid Saliba, MD, Director of Cleveland Clinic’s Electrophysiology Lab and Co-Director of the Ventricular Arrhythmia Center, explains how this lifesaving electrical shock puts the heart back into a normal rhythm.