There are 150,000 newborns with congenital heart disease in China every year. Whether surgery is needed and when is the best time to do it is a problem these parents must face. Improper choice of surgery time can increase the risk of surgery or even lose the chance of surgery, or make the patients who can originally heal themselves suffer from open surgery, so how to choose the timing of surgery? Common precordial diseases include ventricular septal defect, atrial septal defect, and patent ductus arteriosus, which account for half of all precordial diseases. If there are no serious coexisting diseases or serious complications, the success rate of surgery is nearly 100%, and the long-term results of surgery are also very good and can be the same as the quality of life of normal people. However, if there is a combination of serious complications such as pulmonary hypertension, the chance of surgery may be lost or the success rate of surgery may be greatly reduced; even if the surgery is successful, the pulmonary artery pressure of some children will still be progressively aggravated and eventually heart failure or arrhythmia will occur, and the life and quality of life of the children will be seriously affected. Li Fuhai, Department of Pediatrics, Qilu Hospital, Shandong University, 1. Atrial septal defect: Atrial septal defect rarely closes spontaneously, and some studies show that about 1/3 of the first-time patients within 1 year of age can close spontaneously, and the possibility of natural closure after 1 year of age is very small. Because the clinical symptoms and signs of atrial septal defect are not obvious, suspicious heart murmurs are often found during physical examination, and pulmonary hypertension rarely occurs, so the best age for intervention or surgery is preschool (4~5 years old). Indications for surgery are enlarged heart on echocardiogram and chest X-ray, right ventricular or right atrial hypertrophy or bundle branch afferent block on electrocardiogram, and physical development lagging behind that of children of the same age, although these criteria do not necessarily exist at the same time. Most patients with second foramen ovale defects can be treated with interventional therapy instead of surgery.2. Ventricular septal defects: about 21%-63% of patients with ventricular septal defects can be closed spontaneously, the natural closure rate of myocardial defects is higher than that of membranous defects, and the closure rate of small ventricular defects and patients within 1 year of age is high. Small defects (within 5 mm) without pulmonary hypertension and without significant electrocardiographic, echocardiographic and radiographic chest changes do not advocate surgery, but should be followed up to prevent the occurrence of infective endocarditis. surgical repair or interventional closure of defects above 5 mm is recommended before school age (4-5 years). Surgery should be actively considered in small infants with medically uncontrollable heart failure and intractable recurrent pneumonia; some small infants who still have difficulty controlling pulmonary infections with ventilator-assisted breathing may be operated on urgently. Infants and children with pulmonary hypertension, if the pulmonary artery pressure is greater than half of the arterial pressure of the body circulation should be promptly repaired surgically. Interventional treatment is suitable for children with membrane ventricular defect and muscle ventricular defect with a defect of 2-12 mm and age 3 years or older. 3. arteriovenous catheter failure: most of them can avoid surgery and be cured by interventional treatment. Interventional treatment is indicated for children over 3 months of age and 4 kg in weight. The procedure should be performed before school age, but if necessary, the procedure can be performed at any age. The arterial ductus arteriosus can be combined with other precardiac diseases and can become a condition on which children with other complex precardiac diseases depend, such as pulmonary valve atresia and transposition of the great arteries, so closing the ductus in the neonatal period should be done carefully, and oxygen inhalation is contraindicated in these cases.4. Tetralogy of Fallot: Complex precardiac disease is the most common with this disease, and the most debated issue at present is the age of surgery. The disease is 25% dead within 1 year of age, and about 70% of children need ? surgery within the age of one year. In the past, due to the high mortality and complications of one-stage radical surgery in young infants, there was a tendency to perform palliative bypass first, and many hospitals are now using one-stage radical surgery. Early correction is undoubtedly beneficial to the overall development of the child, especially for children with severe hypoxic cyanosis, early surgery should be performed regardless of the age of surgery.5. Other: complete pulmonary venous malformation drainage and complete endocardial cushion defect (atrial septal defect) should be operated within 1 year of age, and early surgery should be considered if combined with heart failure or cyanosis. Partial pulmonary venous malformation drainage and partial endocardial cushion defect can be operated at an optional stage according to the condition because of the mild clinical symptoms, and the best age for surgery is 3-5 years. At present, the field of pediatric precardiac disease is experiencing a special period of development, not only certain precardiac diseases can be cured by surgery, but also many previously inoperable or poorly operated precardiac diseases, such as aortic arch dissection, right heart dysplasia syndrome, single ventricle, tricuspid atresia, pulmonary atresia, right ventricular double outlet, etc., due to changes in surgical methods and the development and updating of surgical materials, the success rate of surgery The success rate of pediatric heart transplantation for the correction of complex malformations has become a routine treatment abroad due to changes in the surgical approach and the development and updating of surgical materials.