Myopericarditis is an inflammatory heart condition involving the pericardium and myocardium. It can lead to heart failure, dilated cardiomyopathy, arrhythmia and sudden death. Its pathogenesis is mainly mediated by viral infections but also can be induced by bacterial infections, toxic substances and immune mediated disorders. All these conditions can produce severe inflammation and myocardial injury, often associated with a poor prognosis. The specific roles of these different pathogens (in particular viruses), the interaction with the host, the interplay with gut microbiota, and the immune system responses to them are still not completely clear and under investigation. Interestingly, some research has demonstrated the contribution of the gut microbiota, and its related metabolites (some of which can mimic the cardiac myosin), in cardiac inflammation and in the progression of this disease. They can stimulate a continuous and inadequate immune response, with a subsequent myocardial inflammatory damage. The aim of our review is to investigate the role of gut microbiota in myopericarditis, especially for the cardiovascular implications of COVID-19 viral infection, based on the idea that the modulation of gut microbiota can be a new frontier in the cardiological field to prevent or treat inflammatory cardiomyopathies.