Prevalence of drug-induced electrocardiographic pattern of the Brugada syndrome in a healthy population.

To determine the prevalence of drug-induced Brugada's syndrome (BrS) electrocardiograms (ECGs) in a healthy population, a sodium channel blockade challenge was performed in previously identified subjects with BrS-compatible (BrC) ECGs. These subjects were detected in 1,000 normal patients in whom first ECGs were systematically recorded. Because of the intermittent nature of electrocardiographic modifications in BrS, second ECGs were also recorded in a representative sample of the population presenting with first ECGs with normal results. The prevalence of typical drug-induced BrS ECGs was 5 of the 1,000 patients. This value was fivefold greater than the reported prevalence of spontaneous BrS ECGs in the healthy population.