Coronary angiography is an effective method for diagnosing coronary artery disease. A catheter is inserted through the femoral artery of the thigh or the radial artery of the forearm, sent to the ascending aorta, then the left or right coronary artery is explored for insertion and contrast is injected to visualize the coronary arteries. This reveals more clearly the anatomical abnormality of the coronary artery and the location, extent and scope of its obstructive lesion. The examination is usually completed in about 30 minutes. Although other tests such as electrocardiogram can also diagnose coronary artery disease, sometimes they are not accurate, and the most accurate way to diagnose coronary artery disease is coronary angiography. Coronary angiography is the only method that can directly observe the morphology of coronary arteries, and it is called the “gold standard” in the medical field. Coronary angiography has important clinical significance: 1) To clarify the diagnosis of coronary artery disease: For those who have atypical angina symptoms but are difficult to diagnose clinically, especially those who have poor therapeutic effect, and for middle-aged and elderly patients with enlarged heart, severe arrhythmia, heart failure, abnormal ECG and suspected coronary artery disease or malformation, but the non-invasive test results cannot confirm the diagnosis, coronary angiography can provide a strong diagnostic basis. 2.For guiding treatment: For patients with clinically confirmed coronary artery disease, if the conservative medical treatment is not good and percutaneous transluminal coronary angioplasty (PTCA) or aorto-coronary artery bypass grafting is considered, coronary artery and left ventricular angiography must be performed first to clarify the site and degree of coronary artery stenosis and the function of the left ventricle, so as to correctly select the treatment The treatment plan. For information only!