Coronary angiography is short for “selective coronary angiography”. It is a kind of examination. 1.Method: A special catheter is inserted into the coronary artery opening after puncturing through the femoral artery or radial artery, and contrast is selectively injected into the coronary artery to record the process of imaging, which is used to determine whether there are lesions in the coronary artery. 2.Significance: It is the international gold standard for the diagnosis of coronary artery disease. 3.Anesthesia: local anesthesia 4.Pathway: formerly: femoral artery-based, currently: radial artery-based 5.Whether it is painful: first, local anesthesia (a little anesthetic in the skin and subcutaneous tissue with a fine needle) is applied to the proposed puncture site (root of the thigh or right wrist), then the vessel is punctured and the catheter is inserted. There are no sensory nerves in the vessels or in the heart, and the patient feels only slight pain during local anesthesia and no significant discomfort during the rest of the procedure. The risk is minimal, relatively safe, and almost painless. Coronary artery disease is short for “atherosclerotic heart disease”. It is a group of clinical syndromes caused by the narrowing or spasm of the coronary arteries in the heart, which leads to ischemia and hypoxia of the heart muscle, resulting in chest pain and tightness. Conventional tests such as electrocardiogram, ambulatory electrocardiogram, exercise panel and myocardial perfusion imaging are indirectly reflecting myocardial blood supply, while coronary angiography is directly seeing the “blood vessels” and “blood flow”, which is the most accurate method of coronary artery disease diagnosis at present.