Coronary artery disease is a heart disease caused by narrowing or occlusion of blood vessels due to atherosclerosis of coronary arteries, resulting in myocardial ischemia and hypoxia or necrosis, also known as coronary atherosclerotic heart disease. The main manifestations are angina pectoris, heart failure, arrhythmia, and myocardial infarction. It has a high incidence and is extremely dangerous. The World Health Organization classifies coronary heart disease into five types: 1. Angina pectoris type: manifested as a feeling of pressure and stuffiness behind the sternum or in the precordial region, accompanied by anxiety, lasting 3 to 5 minutes, often triggered by exertion, emotional excitement, cold, full meals, etc., and relieved by rest and nitroglycerin. Sometimes angina is atypical and may manifest as tightness of breath, weakness, and belching. It is divided into stable and unstable angina according to the frequency and severity of attacks. Stable angina refers to exertional angina that has been attacked for more than one month, and its condition is basically stable. Unstable angina refers to an increase in the frequency, duration and severity of the original stable angina attack, or a new attack of exertional angina, or an attack of angina at rest. Unstable angina is a precursor to acute myocardial infarction, so once found should immediately go to the hospital. 2, myocardial infarction type: manifested as persistent severe pressure, stuffy feeling, or even knife-like pain, located behind the sternum, often spread to the precordial area. The pain site is the same as the previous angina site, but lasts longer and the pain is heavier, which cannot be relieved by rest and nitroglycerin. It is accompanied by irritability, cold sweats, nausea, vomiting, palpitations, dizziness, extreme weakness, dyspnea, and a sense of near death, lasting more than 30 minutes and often several hours. This condition should be seen immediately when detected. 3, asymptomatic myocardial ischemia type: the chance of suffering from plugs and patients with angina pectoris have coronary artery disease after examination, but no symptoms such as chest pain. The reason is that the coronary artery lesion is mild or has better collateral circulation, or the patient has a high pain threshold. Sudden cardiac death occurs in this type of patients as in myocardial infarction people, so attention should be paid to the usual heart care. 4, heart failure type: also known as ischemic cardiomyopathy type, manifested as dyspnea, swelling, palpitations, weakness, etc., may or may not have angina attack, as a result of long-term chronic myocardial ischemia leading to myocardial fibrosis, heart enlargement. 5, sudden death type: refers to sudden death caused by coronary heart disease, caused by cardiac arrest within 6 hours after the appearance of acute symptoms. It is mainly due to the occurrence of coronary artery spasm or embolism on the basis of atherosclerosis, resulting in acute myocardial ischemia, causing local electrophysiological disturbance and temporary severe arrhythmia.