defibrillator

An implantable cardioverter-defibrillator (ICD) is a small electrical impulse generator which operates with an in built battery which is carefully implanted in patients who are at risk of sudden cardiac arrest and even death due to ventricular fibrillation. The device is computer programmed and fine controlled to detect cardiac arrhythmia and correct it by delivering a jolt of pulsed electricity. In current variants, the ability and performance to revert ventricular fibrillation has been extended to include both atrial and ventricular arrhythmias as well as the ability to perform biventricular pacing in patients with congestive heart failure or bradycardia.
The process of implantation of an ICD is very much comparable to implantation of a pacemaker. Similar to pacemakers, these devices typically use electrode wires which pass through a vein to the right chambers of the heart, usually being lodged in the apex of the right ventricle. The difference here is that pacemakers are always temporary and generally designed to consistently correct bradycardia, while AICDs are often permanent safeguards against sudden abnormalities.