Conflicting results on the cardiovascular involvement after SARS-CoV-2 infection generated concerns on the safety of return-to-play (RTP) in athletes. The aim of this study was to evaluate the prevalence of cardiac involvement after COVID-19 in Olympic athletes, who had previously been screened in our pre-participation program. Since November 2020, all consecutive Olympic athletes presented to our Institute after COVID-19 prior to RTP were enrolled. The protocol was dictated by the Italian governing bodies and comprised: 12-lead ECG, blood test, cardiopulmonary exercise test (CPET), 24-h ECG monitoring, and spirometry. Cardiovascular Magnetic Resonance (CMR) was also performed. All Athletes were previously screened in our Institute as part of their periodical pre-participation evaluation. Forty-seven Italian Olympic athletes were enrolled: 83% asymptomatic, 13% mildly asymptomatic, and 4% had pneumonia. Uncommon premature ventricular contractions (PVCs) were found in 13% athletes; however, only 6% (n = 3) were newly detected. All newly diagnosed uncommon PVCs were detected by CPET. One of these three athletes had evidence for acute myocarditis by CMR, along with Troponin raise; another had pericardial effusion. No one of the remaining athletes had abnormalities detected by CMR. Cardiac abnormalities in Olympic athletes screened after COVID-19 resolution were detected in a minority, and were associated with new ventricular arrhythmias. Only one had evidence for acute myocarditis (in the presence of symptoms and elevated biomarkers). Our data support the efficacy of the clinical assessment including exercise-ECG to raise suspicion for cardiovascular abnormalities after COVID-19. Instead, the routine use of CMR as a screening tool appears unjustified.

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A model to predict the ideal reverse leakage currents in Schottky barrier diodes, namely, thermionic emission and tunneling components, has been developed and tested by means of current–voltage–temperature measurements in GaN-on-SiC devices. The model addresses both current components and both forward and reverse polarities in a unified way and with the same set of parameters. The values of the main parameters (barrier height, series resistance, and ideality factor) are extracted from the fitting of the forward-bias I–V curves and then used to predict the reverse-bias behavior without any further adjustment. An excellent agreement with the I–V curves measured in the forward bias in the GaN diode under analysis has been achieved in a wide range of temperatures (275–475 K). In reverse bias, at temperatures higher than 425 K, a quasi-ideal behavior is found, but additional mechanisms (most likely trap-assisted tunneling) lead to an excess of leakage current at lower temperatures. We demonstrate the importance of the inclusion of image-charge effects in the model in order to correctly predict the values of the reverse leakage current. Relevant physical information, like the energy range at which most of the tunnel injection takes place or the distance from the interface at which tunneled electrons emerge, is also provided by the model.

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Unusual clinical course Background:Differential diagnosis between athlete's heart and hypertrophic cardiomyopathy is sometimes challenging in sport cardiology since endurance training can cause a distinct pattern of functional and structural changes of the cardiovascular system. It is of crucial importance to accurately diagnose it and stratify the arrhythmic risk since hypertrophic cardiomyopathy is one of the leading causes of sudden cardiac death in young athletes. Apical hypertrophic cardiomyopathy is a relatively rare form of hypertrophic cardiomyopathy that predominantly affects the apex of the left ventricle and usually has a nonobstructive physiology. Few data and studies are available on influence of aerobic training (and detraining) on morphological changes in athletes with apical hypertrophic cardiomyopathy. Case Report:We present the case of a 19-year-old male soccer athlete with family history for obstructive hypertrophic cardiomyopathy, with electrocardiographic and morphological left ventricular remodeling in association with sports activity. Intensive aerobic training led to marked T-wave inversion on 12-lead ECG and left ventricular hypertrophy compatible with apical hypertrophic cardiomyopathy. Genetic testing confirmed the presence of familial variant c853C>T, p.(Arg 285Cys) on TNNT2 gene. After 18 months detraining, we observed a complete regression of ECG abnormalities and a reverse remodeling of the left ventricular hypertrophy. No pharmacological therapy was indicated; periodic cardiological evaluations were advised. Monitoring devices or implantable cardioverter defibrillator were not recommended. Conclusions:This case suggests that intensive aerobic training can affect the pathological hypertrophic cardiomyopathy substrate, facilitating the development of left ventricular hypertrophy and, more interesting, regression of structural changes after detraining.