If you’ve already had a sudden cardiac arrest then you are at increased risk for having another one. Depending on what caused your sudden cardiac arrest, you may have been offered an Implantable Cardioverter Defibrillator (ICD).
An ICD is a battery-powered device placed under the skin that monitors your heart rate. The ICD is connected to your heart by thin wires. If an abnormal heart rhythm (beating too fast or chaotically) is detected the ICD will deliver an electric shock to restore a normal heartbeat.