Abstract 10920: Programmed Ventricular Stimulation for Risk Stratification in the Brugada Syndrome: A Pooled Analysis

Abstract

Introduction: The role of programmed ventricular stimulation (PVS) in identifying Brugada syndrome patients at highest risk for sudden death is uncertain. Objective: To investigate the utility of PVS to predict future cardiac arrests or ICD therapy for ventricular arrhythmias in Brugada syndrome patients. Methods: We performed a systematic review and pooled analysis of prospective observational studies of Brugada syndrome patients with no history of sudden cardiac arrest who underwent PVS. We estimated incidence rates and relative hazards of cardiac arrest or ICD shock. Results: We analyzed individual-level data from 8 studies, comprising 1312 patients who experienced 65 cardiac events (median follow-up of 38.3 months). A total of 527 patients were induced into arrhythmias with up to triple extrastimuli. Induction was associated with cardiac events during follow-up (HR 2.66, 95%CI 1.44-4.92, P<0.001). Event risks were inversely proportional to the number of extrastimuli causing induction (HR for each fewer extrastimulus protocol relative to individuals not induced 1.69, 95%CI 1.25-2.29, P<0.001). Annual event rates varied substantially by syncope history, presence of spontaneous type 1 ECG pattern, and arrhythmia induction (0.23%, 95%CI 0.05-0.68 [no induced arrhythmia with up to double extrastimuli]; 0.45%, 95%CI 0.01-2.49 [induced arrhythmia]) and highest risk occurring among individuals with syncope and spontaneous type 1 patterns (2.55%, 95%CI 1.58-3.89 [no induced arrhythmia]; 5.60%, 95%CI 2.98-9.58 [induced arrhythmia]; ( Figure ). Conclusion: In Brugada syndrome patients, arrhythmias induced with PVS associate with future ventricular arrhythmia risk. Induction with fewer extrastimuli is associated with higher risk. However, clinical risk factors are important determinants of arrhythmia risk, and lack of induction does not necessarily portend low ventricular arrhythmia risk particularly in patients with high-risk clinical features.