Cardioversion

Internal cardioversion

An internal cardioversion is delivered by a device similar to a pacemaker, called an implantable cardioverter defibrillator (ICD). This device is used for treating ventricular (lower heart chamber) arrhythmias, such as ventricular tachyarrhythmias or fibrillation. The severity of these arrhythmias can cause sudden death because of the dangerously fast heart rate.

Less often, internal cardioversion is needed to treat atrial (upper heart chamber)arrhythmias. In this case, the device is called an "atrial defibrillator".

Implantable defibrillators consist of a pulse generator that is implanted under the skin (just like a pacemaker) and electrodes (wires) that are placed into the heart. If the heart goes into an abnormal rhythm, the defibrillator will sense it and send an electrical shock to the heart, to make it start beating normally again.

The generator battery lasts for several years.