[Brugada syndrome]

Abstract

Brugada syndrome is believed to be responsible for 4 to 12% of all sudden deaths and for 20% of deaths in patients with structurally normal hearts. As a distinct clinical entity with a high risk of sudden cardiac death it was first described in 1992. The syndrome characterized by ST segment elevation in right precoardial leads V1 to V3 unrelated to ischemia and by electrolyte disturbance without obvious structural heart disease. The clinical findings are based on ECG and syncope or sudden death. The arrhythmia leading to sudden death is a rapid polymorphic ventricular tachycardia. The electrocardiographic signature of the syndrome is dynamic and often concealed, but can be unmasked by potent sodium channel blockers such as flecainde, ajmaline. The Brugada syndrome is a familial disease displaying an autosomal dominant mode of transmission with incomplete penetration and with incidence ranging between 5 and 66 per 10,000. The syndrome has been linked to mutations in SCNA5, the gene encoding for the a subunit of the sodium channel. Implantation of an automatic cardiverter-defibrillator is the only currently proven effective therapy.