Indications for the implantable cardiac defibrillator]

The indications of the implantable cardiac defibrillator (ICD) have enlarged over the time. This has been facilitated by the technological progress which permit the device to be more effective and its implantation to be more simple. So, the implantation rate has increased all over the world but especially in the United States. The ICD was initially proposed in case of recurrent cardiac arrests due to ventricular fibrillation. Later, indications have enlarged. They concern at the present time not only the secondary but also the primary prevention of the sudden cardiac death. Indications in secondary prevention are based on the results of randomized studies which have clearly demonstrated the superiority of the device if compared to the antiarrhythmic drugs. The first indication of the ICD in the primary prevention has been defined by the MADIT study. Since, other studies have tried to define high risk population in whom a prophylactic implantation of an ICD should be justified. However, other clinical trials are still necessary to precise the indications of the ICD in some disease states (hypertrophic cardiomyopathy, long QT syndrome, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, Brugada syndrome) which can be complicated by arrhythmic sudden death. Indeed, indications in these diseases are still based on small studies and in the opinion of experts.