Prevalence of Brugada sign and syndrome in patients presenting with arrhythmic symptoms at a Heart Rhythm Clinic in Singapore

Abstract

Southeast Asia is endemic for Brugada syndrome; however, its prevalence in Singapore is unknown. We aimed to determine the prevalence of Brugada sign [Types 1, 2, and 3 Brugada electrocardiogram (ECG)] and syndrome at an arrhythmia clinic in Singapore. Patients who presented with pre-syncope, syncope, and/or palpitations without a known cause at an arrhythmia clinic between 2005 and 2007 were included in the study. The study criteria were met by 392 patients (age: 49.6 +/- 19.1 years, 55.9% male); 675 patients were excluded because they were referred for the management of known diagnoses. The 12-lead ECGs of these patients were analysed and clinical information was abstracted. Brugada sign was observed in 28 patients, and 12 patients were determined to have Brugada syndrome (age: 36.3 +/- 15.4 years, 100% male), yielding a prevalence of 7.1% [95% confidence interval (CI): 4.8-10.2] and 3.1% (95% CI: 1.6-5.3), respectively. The prevalence rates of patients with Type 1, Type 2, and Type 3 Brugada signs were 4.8% (95% CI: 2.9-7.5), 1.8% (95% CI: 0.7-3.6), and 0.5% (95% CI: 0.06-1.8), respectively. Over 30.4 person-years of follow-up, there was one inappropriate defibrillation shock but no appropriate shocks or sudden cardiac deaths among patients with Brugada sign or syndrome. The prevalence of both Brugada sign and syndrome in a hospital-based population in Singapore was found to be high. Further population-based investigation is warranted to confirm these findings.