Prognosis after Implantation of Cardioverter-Defibrillators in Korean Patients with Brugada Syndrome

Abstract

Purpose: Our study aims to analyze prognosis after implantable cardioverter-defibrillator (ICD) implantation in Korean patients with Brugada syndrome (BrS). Materials and Methods: This was a retrospective study of BrS patients implanted with an ICD at one of four centers in Korea between January 1998 and April 2012. Sixty-nine patients (68 males, 1 female) were implanted with an ICD based on aborted cardiac arrest (n=38, 55%), history of syncope (n=17, 25%), or induced ventricular tachyarrhythmia on electrophysiologic study in asymptomatic patients (n=14, 20%). A family history of sudden cardiac death and a spontaneous type 1 electrocardiography (ECG) were noted in 13 patients (19%) and 44 patients (64%), respectively. Results: During a mean follow-up of 59 +/- 46 months, 4.6 +/- 5.5 appropriate shocks were delivered in 19 patients (28%). Fourteen patients (20%) experienced 5.2 +/- 8.0 inappropriate shocks caused by supraventricular arrhythmia, lead failure, or abnormal sensing. Six patients were admitted for cardiac causes during follow-up, but no cardiac deaths occurred. An episode of aborted cardiac arrest was a significant predictor of appropriate shock, and the composite of cardiac events in the Cox proportional hazard model [hazard ratio (95% confidence interval) was 11.34 (1.31-97.94) and 4.78 (1.41-16.22), respectively]. However, a spontaneous type 1 ECG was not a predictor of cardiac events. Conclusion: Appropriate shock (28%) and inappropriate shock (20%) were noted during a mean follow-up of 59 +/- 46 months in Korean BrS patients implanted with an ICD. An episode of aborted cardiac arrest was the most powerful predictor of cardiac events.