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 ven tricular 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 appropri ate 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 pro portional 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 ar rest was the most powerful predictor of cardiac events.