Sudden arrhythmic death syndrome

Ion channelopathies: Long QT syndrome (LQTS), Brugada syndrome, CPVT (catecholaminergic polymorphic ventricular tachycardia), PCCD (progressive cardiac conduction defect), Early repolarization syndrome, Mixed sodium channel disease, Short QT syndrome, Idiopathic ventricular fibrillation (IVF)
Structural heart disease: Arrhythmogenic right ventricular cardiomyopathy (ARVC), Dilated cardiomyopathy (DCM), Hypertrophic cardiomyopathy (HCM), Wolff-Parkinson-White Syndrome (WPW), Mitral valve prolapse (MVP)

Sudden arrhythmic death syndrome
Sudden arrhythmic death syndrome
Other names	Sudden adult death syndrome (SADS), bed death, sudden unexpected/unexplained death syndrome (SUDS), sudden unexpected/unexplained nocturnal death syndrome (SUNDS), sudden death syndrome, sudden death, delayed death
	A type of a deadly ventricular arrhythmia - Ventricular fibrillation pattern seen on an ECG
Specialty	Cardiology
Causes	Ion channelopathies:; Long QT syndrome (LQTS),; Brugada syndrome,; CPVT (catecholaminergic polymorphic ventricular tachycardia),; PCCD (progressive cardiac conduction defect),; Early repolarization syndrome,; Mixed sodium channel disease,; Short QT syndrome, Idiopathic ventricular fibrillation (IVF); Structural heart disease:; Arrhythmogenic right ventricular cardiomyopathy (ARVC),; Dilated cardiomyopathy (DCM),; Hypertrophic cardiomyopathy (HCM),; Wolff-Parkinson-White Syndrome (WPW),; Mitral valve prolapse (MVP);
Risk factors	Family history of heart disease, Asian ancestry, Primary arrhythmia, atherosclerosis, alcohol abuse, type 1 diabetes
Frequency	14.9 per 100,000 people in Japan; 110.8 per 100,000 people in United States

Sudden arrhythmic death syndrome (SADS) is a sudden unexpected death of adolescents and adults caused by a cardiac arrest. However, the exact cause of the cardiac arrest, and thus the exact cause of death, is unknown. These deaths occur mainly during sleep or at rest. One type of conduction defect known as Brugada syndrome can be responsible.

The syndrome is rare in most areas around the world but occurs in populations that are culturally and genetically distinct. It was first noted in 1977 among southeast Asian Hmong refugees in the United States and Canada. The syndrome was again noted in Singapore when a retrospective review of records showed that 230 otherwise healthy Thai foreign workers living in Singapore died suddenly of unexplained causes between 1982 and 1990.