Abstract 14888: Arrhythmogenic Right Ventricular Cardiomyopathy-Brugada Syndrome Overlap: A Rare Clinical Entity

Abstract

Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) and Brugada syndrome (BS) are inherited disorders that predispose individuals to arrhythmic sudden cardiac death. ARVC is a heart muscle disorder of intercellular junctions resulting from mutations of desmosomal (DS) genes, often leading to heart failure, and monomorphic ventricular tachycardia (VT). BS is a channelopathy due to sodium channel mutations, usually presenting as polymorphic VT without cardiomyopathy. Case presentation: A 35-year-old male with history of migraines presented with syncope resulting in a fall. No family history of arrhythmias or sudden cardiac death. Initial EKG showed wide complex monomorphic VT. Repeat EKG (figure 1), revealed coved ST-segment elevations in V1, V2 consistent with Brugada type 1 pattern. Emergent coronary angiography was unremarkable, and echocardiogram showed left ventricular ejection fraction of 55-60%, right ventricle (RV) outflow tract proximal diameter measured 3.5cm and normal RV function. An implantable cardioverter-defibrillator (ICD) was implanted for secondary prevention. Device interrogation on follow-up showed 11 shocks for recurrent episodes of monomorphic VT and patient was started on quinidine maintenance therapy. He remained symptom-free on subsequent visits. Genetic testing was positive for DSC2, DSP, and TMEM43 mutations associated with ARVC, but negative for genes associated with BS. Cardiac MRI results are pending. Discussion: Our patient has overlapping features of ARVC (genotype and monomorphic VT) and BS (EKG with coved ST elevations in V1, V2). Emerging evidence supports the theory that defects in DS proteins may affect the integrity of voltage-gated sodium channels in cardiac intercalated discs, leading to BS like phenotype. Conclusion: ARVC and BS could be related to the same disease spectrum, but further studies are required to understand pathophysiology, to guide treatment decisions.