The majority of myocarditis is viral, and viral myocarditis is often an acute myocarditis attack that is mostly self-limiting, but a small percentage of viral myocarditis, which is not completely cured in the acute phase, can become chronic and turn into chronic myocarditis. Chronic myocarditis is a chronic disease that cannot be cured. As the disease progresses, it can gradually develop into dilated cardiomyopathy, which results in heart enlargement, decreased myocardial contractility, various arrhythmias, and even thromboembolism and sudden death. Therefore, viral myocarditis should be detected and diagnosed early, and treatment should be actively given to avoid acute myocarditis becoming chronic and eventually developing into dilated cardiomyopathy.