The common high-risk factors for various types of cardiac surgery are as follows: 1, congenital heart disease category (1) congenital heart disease “left to right” shunt malformation: this refers to the left atrium, left ventricle and the aorta. The system to the right atrium, right ventricle or pulmonary artery system shunt situation. These conditions, such as mean pulmonary artery pressure greater than 60 mmHg, pulmonary infection or severe respiratory failure, heart failure, and pulmonary vascular resistance greater than 10 Wood units, have a high surgical risk. (2) Congenital cyanotic heart disease: This refers to the presence of a shunt from the right atrium, right ventricle or pulmonary artery to the left atrium, left ventricle or aorta. These diseases such as pulmonary artery dysplasia, pulmonary artery obstruction, hematocrit higher than 20g/100ml, history of syncope and convulsions, heart failure, severely impaired pulmonary, hepatic and renal function, and cardiac arrhythmia are extremely dangerous for surgery. 2.Valvular disease Patients with valvular disease with a cardiothoracic ratio greater than 70%, cardiac function class IV (NYHA classification), history of embolism, long duration of atrial fibrillation, combined with severe pulmonary hypertension, liver and kidney failure, left ventricular end-diastolic internal diameter > 65 mm, and cachexia have a very high risk of surgery. 3.Coronary artery disease Coronary artery left trunk lesions, severe stenosis in all three major vessels, left ventricular ejection fraction (EF) less than 30%, hyperglycemia, hyperlipidemia, smoking, arrhythmia, atrial fibrillation, frequent premature ventricular contractions, and liver and kidney insufficiency are at high risk of surgery. 4.Aortic aneurysm The risk of surgery is very high in patients with aortic coarctation, compression of surrounding organs, aneurysm with excessive length involving distal branches (especially coarctation aneurysm), cardiac insufficiency and liver and kidney insufficiency.