Abstract
BACKGROUND: Previous investigations of predictors of sudden cardiac arrest (SCA) in Brugada syndrome (BrS) have been conducted using manual electrocardiogram (ECG) measurement, which lacks objectivity. This study aimed to examine predictive factors for SCA in BrS using automated ECG measurements. METHODS: In 270 patients with BrS, ECGs were recorded using the same electrocardiograph when a Type 1 ECG was initially observed. The data were digitally acquired and analyzed using identical software. Right precordial leads in the upper one and two intercostal spaces were recorded in all patients. RESULTS: During a median follow-up of 88 months, 28 patients (10%) experienced SCA. Multivariate analysis showed that a history of SCA, history of syncope, R' duration ≥ 18 ms in lead III, and maximum corrected Tpeak-end interval ≥ 137 ms in right precordial leads were independent predictors of SCA. To simplify clinical verification, the presence of an R' wave in lead III was used as a cut-off surrogate. Visual evaluation confirmed that this R' wave remained an independent predictor of SCA in multivariate analysis. All seven patients with BrS who underwent epicardial mapping had fragmented potential at the base of the right ventricular inferior/inferolateral wall. This area corresponded to the most inferior and right-sided region of the ventricle, suggesting lead III may best reflect this region. CONCLUSION: Automated ECG measurement revealed that an R' duration ≥ 18 ms in lead III predicted SCA in patients with BrS. Visual assessment also identified the R' wave in lead III as a novel predictor of SCA.