Brugada syndrome. Clinical data and suggested pathophysiological mechanism. Circulation

The occurrence of ventricular fibrillation (VF) in theabsence of any structural heart disease is classified as “primary electrical disease ” or (in the absence of any relevant findings) “idiopathic VF. ” This diagnosis implies that the arrhythmogenic substrate is inherent to the excitable and conducting properties of the heart. With the exception of a positive family history, demographic variables are, as a rule, not very helpful in establishing the diagnosis of primary electrical disease.1 The paradigm of primary electrical disease is the long-QT syndrome (LQTS), in which altered ionic channel function secondary to mutations in genes encoding ion channels has been shown to underlie QT-interval prolongation.2,3 In 1992, Brugada and Brugada4 described 8 patients with a history of aborted sudden death and a distinct ECG pattern, consisting of right bundle-branch block (RBBB) with ST