The Brugada syndrome: risk stratification.

Abstract

Thirty years after its first description, the knowledge regarding Brugada syndrome has greatly increased. Spontaneous type 1 ECG pattern (BrECG) is a well-defined prognostic marker in asymptomatic patients and is associated with a double risk of arrhythmic events during follow-up as compared to drug-induced ECG pattern. Due to the extreme variability of the ECG pattern over time, the spontaneous type 1 BrECG must be carefully sought, not only through periodic ECGs but especially with repeated 12-lead 24-h Holter monitoring, with V1 and V2 electrodes placed also on the second and third intercostal space, in order to explore the right ventricular outflow tract. 12-lead 24-h Holter should also be performed in all the patients with a dubious BrECG pattern even before the drug challenge with sodium channel blockers, which carries a low but definite risk of complications. In addition to spontaneous type 1, other electrocardiographic markers of increased arrhythmic risk have been described, such as first-degree AV block, QRS fragmentation, S wave in lead I and II, and increased QRS duration. The electrophysiological study in asymptomatic patients with a spontaneous ECG Brugada pattern is still under jury and further studies need to clarify its precise role.