P320 LEFT DOMINANT ARRHYTHMOGENIC CARDIOMYOPATHY: HOW TO STRATIFY THE ARRHYTHMIC RISK? EARLY ONSET CLINICAL CASE. (18th May 2022) - Di Domenico, A
Abstract: Introduction: Arrhythmogenic cardiomyopathy (ACM) is a genetic disease characterized by the progressive replacement of myocardiocytes by fibroadipose tissue that becomes a susbstrate for ventricular arrhythmias with risk of sudden cardiac death. Arrhythmogenic cardiomyopathy can manifest itself through three different phenotypes: the classic phenotype, the most frequent, involving only the right ventricle, the biventricular variant with possible right or left dominance and the rare variant involving only the left ventricle. We present a case of left ventricular arrhythmogenic cardiomyopathy. Case Report: 16–year–old male patient in complete physical well–being, with no significant medical history and a negative family history of heart disease and/or sudden cardiac death (Fig. 1 ). He practiced competitive sports for years with periodic medical–sports visits. In 2017, ventricular extrasystole was detected on the electrocardiogram, for which he performed cardiological investigations. On electrocardiogram: sinus rhythm with QRS fragmented into DIII and aVL and negative T waves from V4 to V6 (Fig. 2 ). On transthoracic echocardiography, evidence of normal cavity dimensions, ejection fraction at lower normal limits (42%) and left ventricular trabeculation, in the absence of significant valvulopathy. He then performed a cardiac MRI that showed: left ventricle moderately dilated and hypokinetic with widespread alterations of myocardial signal secondary to fibroadipose replacement phenomena, configuring a picture of left ventricular dilation and dysfunction referable to arrhythmogenic left ventricular cardiomyopathy (Fig. 3 ). The patient was also subjected to genetic analysis aimed at searching for mutations of genes involved in arrhythmic heart disease, which was negative. In light of the absence of conclusive scientific evidence on the implantation of a defribrillator in primary prevention in clinical–instrumental cases such as the present, the risk of infection and the risk of inappropriate discharges, it was proposed the implantation of a loop–recorder in order to monitor and record any arrhythmic events, starting beta–blocker therapy. The possibility of continuing competitive physical activity was therefore denied. Conclusions: Currently, guidelines on ACM and diagnostic criteria focus mainly on the right variant, so there are no clear indications to stratify arrhythmic risk in left ventricular ACM.