Loss-of-function mutations in the SCN5A gene, which encodes Nav1.5 channels, underlie several inherited arrhythmogenic syndromes, including Brugada syndrome (BrS).
Loss-of-function mutations in SCN5A, the gene encoding Na(v)1.5 Na+ channel, are associated with inherited cardiac conduction defects and Brugada syndrome, which both exhibit variable phenotypic penetrance of conduction defects.
We characterized a novel double mutation of SCN5A (V232I in DI-S4+L1308F in DIII-S4) identified in a rare case of lidocaine (1 mg/kg)-induced Brugada syndrome.
While a reduction in INa due to SCN5A mutation is implicated as the underlying mechanism in Brugada syndrome, hyponatremia, which can give rise to a reduced INa, has never been reported in literature as a cause or precipitating factor in this syndrome.
Our findings indicate that bupivacaine may induce the electrocardiographic and arrhythmic manifestations of the Brugada syndrome in silent carriers of SCN5A mutations.
The aim of the present study was to screen for mutations in the SCN5A gene in a family with BS, and to characterize the consequences of the mutation on channel function.
A mutation in the cardiac sodium channel gene (SCN5A) has been described in patients with the syndrome of right bundle branch block, ST-segment elevation in leads V1 to V3, and sudden death (Brugada syndrome).