Brugada syndrome and Brugada-type electrocardiogram.
The Brugada syndrome is an inherited arrhythmogenic and nonstructural heart disease that may cause syncope and sudden cardiac death (SCD). It is characterized by ST segment elevation in the right precordial leads (V1-V3) and male predominance. Mutation on SCN5A encoding the alpha-subunit of the sodium channel is seen in 20%-30% of patients with the syndrome. Because of low penetrance of gene mutation, clinical manifestations and prognosis can be variable in individuals. Therefore, asymptomatic population with Brugada-type electrocardiogram (ECG) exists in community and SCD risk stratification of the individual can be problematic. Although understanding of the cellular mechanism of the syndrome has advanced, there are conflicting data about its prevalence and prognosis. Population-based genetic epidemiology studies with longer follow-up periods may be able to elucidate clinical outcome of the syndrome, particularly asymptomatic patients.