[Covid-19, myocarditis and return to play: it's time to be conservative.]

Observational studies of cardiac magnetic resonance imaging in people with recent covid-19, including young asymptomatic athletes, have documented variable amounts of myocardial findings deemed suggestive of myocarditis. Despite a critical appraisal of the current literature points toward an insufficient evidence base about the existence of a peculiar association between covid-19 and myocarditis, the concern for unrecognized myocarditis and its potential consequences has led several sports medicine organizations to recommend a variety of cardiac tests to enable return to play in athletes with previous covid-19. We argue that some of these recommendations may lead to unnecessary tests or treatments, especially for asymptomatic SARS-CoV-2 positive people and for those with previous mild disease, and that sports participation may even be discouraged. As a response to current uncertainty, we advocate both for randomized studies that analyse the outcomes of different diagnostic strategies and for a prolonged follow-up of these people.