P4422Myocarditis: a deceitful but not infrequent athletes' enemy

Abstract

Abstract Introduction Myocarditis represents a not negligible cause of sudden death (SD) in athletes, representing the cause of 4%-14% cardiac arrests and deaths in athletes. Preparticipation screening including 12-leads basal electrocardiogram could drastically reduce SD in athletes and screening programs are therefore now recommended by most medical and sport association. At the moment, no data in literature are available about incidence of concealed myocarditis in athletes but there is general consensus about disqualification from competitive sport in the presence of myocardial fibrosis (MF). Purpose Purpose of our study was to quantify incidence of MF consistent with past myocarditis in athletes that referred to our Sport Cardiology Center for ventricular arrhythmias (VA) +/− repolarization abnormalities (RA) detected at preparticipation screening. Methods In our study we retrospectively evaluated all athletes with VA +/− RA and we quantified how many were found to have MF consistent with myocarditis at cardiac MRI. Furthermore, we evaluated characteristics of presentation in terms of clinical symptoms of myocarditis and frequency and morphology of VA. Finally, we analyzed findings of invasive diagnostic workout when performed. Results In the last two years we evaluated 111 athletes for VA +/− RA and we found MF consistent with myocarditis in 18 (16%) of them. Only 2/18 referred past febrile status probably correlated with myocarditis and 1 had symptoms consistent with acute myocarditis. Number of VA was not correlated with MF fibrosis, while polymorphic VA and exercise-correlated VA were the most frequent finding. 5/18 (28%) had also rest and/or exercise induced RA. 10/18 (55%) athletes underwent electrophysiological study without any induction of arrhythmias. 7/18 (39%) underwent also electroanatomical mapping (EAM) with pathological findings in 5/7 (71%). All of these 5 underwent endomyocardial biopsy guided by EAM and in 2 cases bioptic findings were consistent with arrhythmogenic cardyomyopahty (ACM). All 18 athletes were disqualified from competitive sport as for Italian Sport Medicine protocols. Conclusion MF consistent with past myocarditis is a not infrequent finding in athletes with VA with or without RA. Morphology and exercise behavior of VA are the most important “alarm bell”, while VA number is not correlated with MRI pathological findings. Sometimes MF interpreted as consistent with past myocarditis is actually the manifestation of ACM. Identification of these diseases is of extreme importance for athletes' safety.