Dilated cardiomyopathy is a common clinical condition and can be diagnosed through clinical examinations, as follows: 1. X-ray examination: X-ray examinations often show an enlarged heart shadow with a spherical appearance in the late stage, indicating that all heart chambers are enlarged and the appearance is quite similar to pericardial effusion. In a few patients, enlargement of the left ventricle, left atrium or right ventricle is predominant, with an appearance similar to mitral valve disease. Fluoroscopy reveals a weaker-than-normal heartbeat. The aorta is usually not enlarged. Patients with longer duration of disease often have pulmonary stasis and interstitial edema, and there may be septal lines at the angle of the rib diaphragm in both lungs, and the pulmonary veins and pulmonary arteries may be enlarged. Left ventricular hypertrophy is more common, often combined with myocardial strain, and right ventricular hypertrophy is often present in late stages; left or right atrial hypertrophy may also be present; 3. Echocardiography: mild enlargement of the heart chambers can be seen early in the disease, and all chambers are enlarged in later stages; 4. Nuclear ventriculography: can also show enlargement of the heart chambers with reduced ventricular wall motion and reduced left ventricular ejection fraction, which is more obvious after exercise; 5. Cardiac catheterization; 6. Endomyocardial biopsy. It can determine whether myocardial inflammation is present.