| Abstract: | Background: Recent studies suggest that the Brugada‐type electrocardiogram (ECG) is much more prevalent than the manifest Brugada syndrome. Although invasive electrophysiologic investigations have been proposed as a risk stratifier, their value is controversial, and alternative noninvasive techniques may be preferred. We sought a noninvasive strategy to detect a high‐risk group in a long‐term follow‐up study of subjects with a Brugada‐type ECG, and no history of cardiac arrest. Methods: This study enrolled 124 consecutive subjects with a Brugada‐type ECG. Prognostic indices included: age, sex, a family history of sudden death, syncopal episodes, a spontaneous coved‐type ST‐segment elevation, maximal magnitude of ST‐segment elevation, a spontaneous change in ST segment, a mean QRS duration, maximal QT interval, QT dispersion, late potentials (LP) by signal‐averaged ECG, and microvolt T‐wave alternans. Results: Of the 124 subjects, 20 consenting subjects had an implantable defibrillator before follow‐up. During a 40 ± 19‐month follow‐up, 12 subjects (9.7%) reached one of the endpoints (sudden death or ventricular tachyarrhythmia). Of the 12 risk indices, a family history of sudden death, syncopal episodes, a spontaneous coved‐type ST‐segment elevation, a spontaneous change in ST segment, and LP had significant values. In multivariate analysis, a spontaneous change in ST segment had the most significance (a relative hazard, 9.2; P = 0.036). Combined assessment of this index and other significant indices obtained higher positive predictive values (43–71%). Conclusions: A spontaneous change in ST segment is associated with the highest risk for subsequent events in subjects with a Brugada‐type ECG. The presence of syncopal episodes, a history of familial sudden death, and/or LP may increase its value. |
