Brugada syndrome (BS) is a genetic disorder characterized by dysfunction of the cardiac sodium channels, particularly involving mutations in the
SCN5A gene, which encodes the predominant cardiac sodium channel alpha subunit NaV1.5
Pathophysiology
- The electrophysiological substrate of BS is primarily located in the right ventricular outflow tract, where slow discontinuous conduction and steep dispersion of repolarization are present
- Genome-wide association studies have identified multiple loci associated with BS, indicating a strong polygenic influence and highlighting the role of transcriptional regulation in BS pathogenesis
Prognosis
- The prognosis of BS is variable and depends on several factors. Patients who have experienced aborted sudden cardiac death (SCD) or syncope have a higher risk of future cardiac events, with annual event rates of 7.7% and 1.9%, respectively
- In asymptomatic patients, the incidence of severe arrhythmic events is very low, with an annual event rate of 0.5%
- Men with BS present with a greater risk clinical profile than women and have a worse prognosis
Risk factors
- Risk factors for BS include a family history of the syndrome and the presence of specific genetic mutations, particularly in the SCN5A gene
- A previous history of aborted SCD or syncope and the presence of a spontaneous type 1 ECG are predictors of adverse outcome
- Gender differences have been observed, with men presenting a greater risk clinical profile than women
In conclusion, BS is a genetic disorder characterized by dysfunction of cardiac sodium channels, primarily involving mutations in the
SCN5A gene. The prognosis is variable, with a higher risk of future cardiac events in patients who have experienced aborted SCD or syncope. Risk factors include a family history of the syndrome, specific genetic mutations, and gender differences.