Overview of sudden cardiac deaths

Sudden cardiac death (SCD) is an unexpected cardiac death that is instantaneous or occurs within a short period of time after onset of symptoms, in a person in a stable state of health. SCD has either a certain etiology (for example, cardiac tamponade or fresh occlusive coronary thrombus), or has one or more morphologic substrates that increase the risk of electrical instability that in turn can lead to a fatal arrhythmia. The latter group of SCD has been assigned as either highly probable or uncertain etiologies, according to guidelines of the Association of European Cardiovascular Pathology. This review describes definitive causes and potential underlying substrates for SCD.