Monomorphic ventricular tachycardia in patients with Brugada syndrome: A multicenter retrospective study.

Background: Isolated cases of monomorphic ventricular tachycardia (MVT) in patients with Brugada syndrome (BrS) have been reported.
Objective: We aimed to describe the incidence and characteristics of MVT in a cohort of patients with BrS who had received an implantable cardioverter-defibrillator (ICD).
Methods: Data from 834 patients with BrS implanted with an ICD in 15 tertiary hospitals between 1993 and 2014 were included.
Results: The mean age of enrolled patients was 45.3 ± 13.9 years; 200 patients (24%) were women. During a mean follow-up of 69.4 ± 54.3 months, 114 patients (13.7%) experienced at least 1 appropriate ICD intervention, with MVT recorded in 35 patients (4.2%) (sensitive to antitachycardia pacing in 15 [42.8%]). Only QRS width was an independent predictor of MVT in the overall population. Specifically, 6 (17.1%) patients presented with right ventricular outflow tract tachycardia (successfully ablated from the endocardium in 4 and epicardial and endocardial ablation in 1), 2 patients with MVT arising from the left ventricle (1 successfully ablated in the supra lateral mitral annulus), and 2 (5.7%) patients with bundle branch reentry ventricular tachycardia. Significant structural heart disease was ruled out by echocardiography and/or cardiac magnetic resonance imaging.
Conclusion: In this retrospective study, 4.2% of patients with BrS implanted with an ICD presented with MVT confirmed as arising from the right ventricular outflow tract tachycardia in 6, patients with MVT arising from the left ventricle in 2, and patients with bundle branch reentry ventricular tachycardia in 2. Endocardial and/or epicardial ablation was successful in 80% of these cases. These data imply that the occurrence of MVT should not rule out the possibility of BrS. This finding may also be relevant for ICD model selection and programming.
(Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)