The body generates electrical impulses that cause the heart to beat. In some people, those electrical impulses don't happen in a normal pattern, which can cause the heart to beat too slowly, too fast or irregularly. A very fast heartbeat can lead to ventricular tachycardia, a potentially life-threatening condition. In patients who are at risk for ventricular tachycardia, doctors often recommend an implantable cardioverter defibrillator or ICD.
