The normal pulmonary valve is a three semilunar valve with complete separation at the leaflet junction, and the leaflet is connected to the right ventricular funnel muscle. In most typical pulmonary stenoses, the intact leaflet structure and junction are visible, but the junction is fused with adhesions and the leaflets are thickened, forming a centripetal or eccentric cavity-like stenosis. Poor mobility. In typical pulmonary valve stenosis, the pressure difference between the pulmonary artery and the right ventricle (△P) ≥ 6.67 kPa (50 mmHg) at normal cardiac output is the absolute indication for PBPV treatment; in typical pulmonary valve stenosis, the electrocardiogram shows an enlarged right ventricle, the right ventriculogram shows dilated pulmonary artery, the presence of the jet sign, and the pressure difference across the pulmonary valve is 4.67 kPa~6.67 kPa. kPa to 6.67 kPa (35 mmHg to 50 mmHg) as relative indications for PBPV treatment. Regarding the age of surgery: If the pulmonary stenosis is moderate or severe, it is advisable to perform PBPV early so as to facilitate the recovery of the child’s right heart function. In general, it is better to perform PBPV between 1 and 3 years of age, and complications are less frequent. However, the specific age of surgery should be determined by the conditions of the operator’s unit (operator’s experience and technical ability, instrumentation conditions, and level of postoperative monitoring, etc.). In some children with mild pulmonary stenosis (trans-pulmonary valve pressure difference less than 30 mmHg), PBPV may not be performed urgently if there are no clinical symptoms. The growth of this group of children is usually not affected, and the murmur can be reduced or disappeared in some children with growth and development. For children with right ventricular dysplasia, right heart insufficiency, significant tricuspid regurgitation, and severe pulmonary artery dysplasia, PBPV is usually not recommended, and surgery should be the first choice. 2.Pulmonary valve balloon dilatation preoperative preparation Preoperative examination: Patients should be examined by physical examination, electrocardiogram, X-ray chest film and echocardiography before PBPV to initially determine the type of pulmonary valve stenosis and its severity. Preoperative preparation: Penicillin skin test, iodine allergy test, bilateral inguinal skin preparation (after skin preparation, please take a shower and change clean clothes), and bed training for bowel movement and urination (to prevent difficulty in defecation after surgery, because it is necessary to lie flat for 24 hours after surgery and cannot get out of bed) should be performed before surgery. You should fast for 6 hours and fast from water for 2 hours before surgery, but take your daily oral medication as usual except stop taking hypoglycemic drugs and portable blockers on the day of surgery (please take Bamil with warm boiled water). Empty urine and stool half an hour before surgery and remove all body ornaments. 3.Pulmonary valve balloon dilatation operation method There are two methods of pulmonary valve balloon dilatation used: polyethylene balloon catheter method and Inoue balloon catheter method. The former is mostly suitable for children weighing less than 20 kg, and the latter is mostly suitable for older children and adults. Both are performed by puncturing the femoral vein at the base of the patient’s right thigh and inserting a dilator tube to reach the narrowed pulmonary valve orifice. Generally, the heart murmur can still be heard after surgery, but it is significantly reduced compared with the preoperative period, mostly due to hypertrophic stenosis of the inferior pulmonary valve muscle. 4, the advantages of pulmonary valve balloon dilation Pulmonary valve stenosis, can be percutaneous pulmonary valve balloon dilation or valve dissection under extracorporeal circulation. Traditional pulmonary valvotomy under extracorporeal circulation requires open-heart surgery under general anesthesia, which is very traumatic and has a long postoperative recovery period. Percutaneous pulmonary valve balloon dilatation is usually performed under x-ray surveillance with insertion of a catheter with a balloon, and a small amount of contrast is injected as it enters the right ventricle to further clarify the diagnosis. The position of the valve is seen and the catheter is extended into the main pulmonary artery so that the middle of the balloon is at the valve. The balloon is injected with contrast agent to raise its pressure and tear the stenotic valve. If the procedure is unsuccessful, it can be repeated, and the pressure step difference between the right ventricle and the pulmonary artery is measured for each dilatation until the pressure step difference is significantly reduced and the dilatation is satisfactory. Interventional procedures are increasingly favored by doctors and patients because they do not require general anesthesia, are minimally invasive, and have rapid recovery. 5.Pulmonary valve balloon dilatation postoperative attention First: the pulmonary valve balloon dilatation only punctures the femoral vein, so the lower extremity of the punctured side should be braked for 4 to 6 hours after surgery, and the entire bed rest time is 6 to 12 hours, the specific time is determined by the doctor according to the different characteristics of each patient. During the first 4 to 6 hours of bed rest, the patient cannot raise his head by himself, cannot bend the lower limb of the punctured side, and cannot lie on his side. Second: precisely because of the long postoperative bed rest, the patient should begin training to urinate and defecate in the bed position before surgery to facilitate the postoperative transition. Third: Postoperative acute or subacute stent thrombosis usually occurs within 24 hours to 2 weeks after stent implantation. Patient emotional stress at this stage is a common trigger for coronary artery spasm. Sustained intense coronary spasm can lead to platelet aggregation in the stent. Thrombosis or vessel occlusion. Therefore, it is important to pay attention to health and psychological care before and after the procedure, while patients themselves need to relax. Fourth: Sudden symptoms such as chest tightness, chest pain, sweating and panic should be reported to the doctor immediately. Further examination should be done to clarify whether there is thrombosis. Fifth: postoperative intravenous antibiotics are usually applied for 3 days. For patients with postoperative outflow tract spasm, blood pressure, heart rate and right heart failure should be noted, and p-blockers or calcium antagonists should be given if necessary. Sixth: Review echocardiogram, electrocardiogram and x-ray cardiography 6 months after pulmonary valve balloon dilatation. Avoid heavy physical activity until the electrocardiogram returns to normal.