Dilated cardiomyopathy (dilated cardiomyopathy) is a cardiomyopathy of undefined etiology, characterized by enlargement of the left ventricle, right ventricle or both chambers and systolic dysfunction, etc. Diagnosis is facilitated by cardiac ultrasound. Clinical manifestations are dominated by reduced left ventricular systolic function, progressive heart failure, arrhythmias, thromboembolism and sudden death. Etiology: 1. Idiopathic: the cause is unknown, some literature reports about 50%. 2. Familial: 25%-50% have gene mutation or family genetic background. 3. Secondary, may be caused by other diseases, immune or environmental factors. 2. Clinical manifestations: early manifestations are ventricular enlargement and arrhythmias, then gradually develop into heart failure, and the 5-year survival rate is only 50% after the appearance of heart failure symptoms. The treatment of dilated heart disease is mainly to improve the symptoms, prevent complications and stop the progression of the disease, and a small number of patients whose condition deteriorates need to undergo heart transplantation. Treatment: 1. Etiological treatment: actively search for the cause of the disease, exclude any possible causes of myocardial disease and give active treatment, such as control of infection, strict restriction or abstinence from alcohol, change of poor lifestyle, etc. 2.Pharmacological treatment: According to the early, middle and late stages of the disease, different treatments are given, such as in the early stage: only changes in the structure of the heart, β-blockers, ACEI are given. in the middle stage: (1) reasonable use of diuretics. (2) ACEI or ARB should be used aggressively in all those without contraindications.(3) β-blockers should be used in all patients with stable disease and LVEF <40%. (4) Spironolactone and digoxin may be used in patients with moderate or severe manifestations of heart failure without severe impairment of renal function. (5) Amiodarone and others may be used in patients with arrhythmias leading to the risk of sudden cardiac death. In the advanced stage: on top of diuretics, ACEI/ARB, digoxin and other drug therapy, short-term application of orthomimetic drugs such as dobutamine and phosphodiesterase inhibitor milrinone can be considered. In addition, oral aspirin 75-100 mg/d is required to prevent attachment thrombosis. For patients who already have attachment thrombosis and thromboembolism must be treated with long-term anticoagulation, oral warfarin, and INR maintained between 2.0-2.5. 3. Non-pharmacological treatment ①Pacing therapy: For patients with dilated heart disease with sick sinus syndrome or atrioventricular block, pacemakers can help to improve heart rate, increase heart beat volume and improve clinical symptoms. (2) Resynchronization therapy (CRT): (3) Radiofrequency ablation therapy: radiofrequency ablation is performed for dilated heart disease with chronic atrial flutter. 4, surgical treatment (1) left ventricular decompression surgery. (2) left heart assist device. (3) heart transplantation. 5, other treatment methods still being explored, such as immunotherapy, cell transplantation, etc.