Chronic myocarditis is a more serious disease that develops from untreated acute myocarditis. Chronic myocarditis is a chronic disease, and it is incurable. As the disease progresses, it can gradually lead to heart enlargement, decreased myocardial contractility, various arrhythmias, and sometimes thromboembolism, and even sudden death. Patients with chronic myocarditis should be given long-term ACEI, ARB, and beta-receptor antagonists to reduce myocardial remodeling, slow down the progression of the disease, and improve the patient’s prognosis. For patients with heart failure, diuretics should be given to reduce the cardiac load, and if necessary, digitalis preparations should be used to enhance myocardial contractility to improve heart failure symptoms.