The heart is supplied with blood by three vessels: the right coronary artery and the left coronary artery, which is subdivided into the anterior descending and gyral branches. Each vessel has its own area of supply, which ensures the normal physiological activity of the myocardial tissue in this area. Coronary angiography is the gold standard for clear off coronary artery disease. What should we do if we find different degrees of stenosis in the coronary arteries? 1. Treatment strategy depends on the degree of stenosis What is the degree of stenosis? Mild stenosis, moderate stenosis or severe stenosis. In mild and moderate stenosis, only pharmacological intervention is needed, along with active control of risk factors and improvement of lifestyle, because mild to moderate stenosis does not affect the coronary blood supply and can be effectively controlled by pharmacological intervention. Severe stenosis (>75%) requires stenting to improve myocardial ischemia, reduce cardiovascular events, and prevent acute myocardial infarction. The lumen forms a severe stenosis and the composition of the plaque is often determined by two forms, one is soft plaque and the other is calcified plaque. This is like a blockage in the kitchen drain at home, whether the blockage is a recently formed garbage or a blockage gradually formed by the accumulation of garbage over time, for the plumber, it must be easier to unblock the newly formed garbage, spending the least amount of money and using the least amount of tools. As far as the patient is concerned, the doctor who implanted the stent is like a plumber who finds a severe stenosis, the sooner it is treated, the less difficult it is for the doctor to operate and the least costly for the patient and family, which is the best of both worlds. The treatment of severe calcified plaques over time often involves the use of various consumables, such as coronary artery rotational grinder, cutting balloons, spinal balloons and different types of common balloons, to dilate this diseased vessel and then implant a stent, when not only the difficulty of the operation increases gradually, but also the cost of the operation increases geometrically. Therefore, for severe stenosis, it is important to deal with it early and benefit from it early, not only to greatly reduce the occurrence of acute cardiovascular events, but also to reduce the cost of surgery. 2, timing of surgery For most patients, after coronary angiography, severe stenosis is found, stent implantation can be started as soon as the family or patient agrees, in order to reduce the pain caused by the second puncture of the radial or femoral artery, which greatly improves the efficiency of the procedure and reduces the patient’s pain, therefore, as a cardiovascular interventional surgeon, we must encourage everyone to find the problem Immediate solution. Unless risk factors are found during coronary angiography, it is recommended to complete the procedure at an elective stage, such as special lesion sites, involving bifurcation lesions, thrombosis, unstable patient vital signs, etc. Further patient adjustments and drug interventions are needed, and when the patient is in a stable state, coronary stenting will be performed at an elective stage. 3, coronary angiography interval: one week When you see the doctor play the dynamic image of coronary artery, you will see the blood vessel very clear shadow, in fact, a special liquid – contrast agent is used in the procedure. The use of contrast agent may pose two risks to patients: contrast nephropathy and contrast allergy. First, the contrast agent is injected into the body, and after the task of vascular development is completed, it is completely required to be metabolized and eliminated from the body through the renal excretion. Therefore, if a large amount of contrast agent is used for a short period of time, it will aggravate the risk of contrast nephropathy in patients. A one-week interval between two imaging sessions can effectively eliminate the contrast agent from the body and safely perform a second imaging examination. In order to further reduce the allergic reaction caused by contrast agent, it is recommended that patients drink more water after the procedure, which can effectively promote the metabolism of contrast agent and further reduce the possibility of contrast agent allergy, and then perform coronary angiography in a week’s interval, which can avoid the superimposed effect of contrast agent and greatly reduce the risk of contrast agent nephropathy. The possibility of allergic reaction to contrast agent can be greatly reduced.