1. When is surgery appropriate for tetralogy of Fallot? Why? What types of surgery are there? The timing of surgery for tetralogy of Fallot varies depending on the condition of the child. Since all tetralogy of Fallot have different degrees of hypoxia, early surgery is recommended once the diagnosis is clear. With the improvement in the overall level of cardiac surgery, it is safer to perform radical surgery in children with tetralogy of Fallot under 4 months of age. If the child is stable, does not have frequent episodes of hypoxia, and is growing well, surgery can be considered between 6 months and 1 year of age. If the child has recurrent episodes of hypoxia or syncope, surgery should be performed as soon as possible, regardless of the age of the child, to avoid serious complications such as severe hypoxia affecting the growth and development of the child and even brain tissue damage. There are two types of surgery for tetralogy of Fallot, broadly speaking, radical surgery and palliative surgery. Surgical procedures that correct both anatomical and physiological aspects are called radical surgery, while palliative surgery aims to increase pulmonary blood flow, expand the pulmonary vascular bed, promote pulmonary vascular development, and prepare for radical surgery on the basis of eliminating and improving symptoms such as cyanosis. The modalities of palliative surgery include: body-pulmonary bypass, central bypass and pulmonary valve balloon dilation, while body-pulmonary bypass includes, for example, subclavian artery-pulmonary artery bypass (i.e., B-T bypass) and ascending aortic and pulmonary artery bypass. Due to the development of cardiac surgery technology, the indications for one-stage radical surgery have been relaxed year by year, and the number of surgeries has increased year by year, while the number of decompression surgeries has decreased year by year, and is only used for patients with very poor pulmonary artery development and other serious intracardiac malformations that are not suitable for one-stage radical surgery. 2. What is the approximate cost of surgery for tetralogy of Fallot? Radical surgery: 1) for children aged 4-6 months, the cost is 50,000-60,000 RMB 2) for children aged 6-12 months, the cost is 40,000-50,000 RMB 3) for children aged 1 year or older, the cost is less than 40,000 RMB Palliative surgery: due to the wide variation of the disease, the cost of surgery varies from 30,000-60,000 RMB. 3.Why do I need regular follow-up after the surgery of Act IV? Can I get vaccination? Although most children are able to complete the radical surgery for Tetralogy of Fallot, only 80% of them have a quality of life close to that of a normal person, and another 20% will definitely be worse than normal. If the child’s condition is stable after surgery and the heart function is good, most children can have vaccination after 3-6 months after surgery, i.e., vaccination. 4.What are the complications of surgery for tetralogy of Fallot? What is the prognosis of surgery? l) Low cardiac output syndrome is the most common complication after radical surgery for tetralogy of Fallot, which mainly occurs in the early postoperative period and generally does not affect the long-term prognosis as long as the child can survive the dangerous period of surgery. 2) Respiratory distress syndrome is also a common complication after radical surgery for tetralogy of Fallot. Postoperative pulmonary vascular hyperperfusion in patients with pulmonary vascular dysplasia is the main cause of respiratory distress syndrome. With the continued availability of perioperative management, the vast majority of children and others are sufficiently cured. 3) Arrhythmias are not uncommon after radical surgery for tetralogy of Fallot. Atrioventricular block that occurs early in the postoperative period is mostly related to surgical technique. Once a high degree of atrioventricular block occurs, a temporary pacemaker should be placed, and non-organic injuries can mostly be recovered within 3-5 days. Supraventricular tachycardia, in the early stage, is mostly caused by myocardial injury or hypoxia. Late onset of supraventricular tachycardia is usually due to outflow tract obstruction and requires reoperation to remove the obstruction. Premature ventricular contractions and ventricular tachycardia occur in the late stage and can lead to sudden death, so they should be monitored with regular follow-up after surgery. 4) Renal insufficiency is also a common complication after radical surgery for tetralogy of Fallot. Patients with tetralogy of Fallot often have different degrees of renal impairment due to long-term hypoxia, so attention should be paid to protect renal function during the perioperative period. When renal insufficiency occurs, peritoneal dialysis can be considered for infants and children, and hemodialysis can be considered for adults. It can usually be cured. 5) Residual shunts in ventricular septal defects are mostly incomplete repair of the defect and can also be seen in undetected multifocal muscle ventricular defects. If the residual shunt is large and the ventricular septal defect is more than 5 mm in infants and children, reoperative repair should be considered if it affects the patient’s cardiopulmonary function. 6) Residual stenosis of the right ventricular outflow tract is mostly seen in the pulmonary valve annulus, but can also occur distal to the widened patch of the right ventricular outflow tract, mostly due to unsatisfactory outflow tract sparing or insufficient patch widening. These patients are prone to right heart failure, tricuspid regurgitation, low cardiac output syndrome and various arrhythmias, and even sudden death. 5.What are the risks of tetralogy of Fallot? The natural prognosis of tetralogy of Fallot depends mainly on the severity of right ventricular outflow tract obstruction, and the majority of patients die from hypoxia or heart failure. Therefore, tetralogy of Fallot should be treated surgically as early as possible. The more severe the obstruction of the right ventricular outflow tract to the pulmonary artery, the less blood flow to the lungs and the more severe the cyanosis and tissue hypoxia,. Severe cyanosis is often present in those with distal pulmonary artery dysplasia. As the left heart is poorly developed, the right heart is heavily burdened and becomes increasingly aggravated with age, eventually leading to heart failure. 6.What are the signs and symptoms of tetralogy of Fallot? Cyanosis is the most prominent symptom of the disease, mostly in infancy, but in the early months after birth it may not be obvious due to the presence of unclosed ductus arteriosus, or may only appear when crying. Shortness of breath and paroxysmal dyspnea are also common symptoms, mostly after crying or exertion, and are more common in infants and children between two months and two years of age. Children often have squatting, which is characterized by walking a certain distance and then squatting, with both lower limbs flexed and both knees against the chest. Squatting reduces the return of less oxygenated blood to the heart, while the femoral artery bends due to squatting, resulting in increased resistance to blood flow in the arteries of the lower extremities and increased blood flow in the upper trunk, resulting in improved central nervous system hypoxia. In addition, increased resistance of body circulation may increase leftward there shunt at the ventricular level, resulting in increased blood flow to the pulmonary circulation and improved cyanosis. Severely ill patients may have hypoxic episodes, which manifest as pallor, weakness of the limbs, paroxysmal syncope, or even convulsions, mostly in the early morning, after defecation or activity. The exact mechanism of hypoxic attack is not cleared, which is related to a sudden decrease in pulmonary blood flow due to a decrease in vascular resistance of the body circulation or contraction of the muscles in the funnel of the right ventricle, or may be caused by an increase in right-to-left shunt at the level of the ventricle causing a large flow of hypoxic blood into the aorta. Patients with severe tetralogy of Fallot with episodes of hypoxia should be operated on as early as possible in infancy, and those with frequent episodes should be operated on as a matter of urgency. Patients are generally poorly developed, emaciated, with marked cyanosis of the lips and mouth, and in severe cases, the face and auricles. There are cyanosis and pestle-shaped fingers (toes) at the end of the extremities due to hypoxia, and the severity of the pestle-shaped fingers (toes) is directly proportional to the degree of hypoxia. In some infants and young children, the cyanosis may be clinically insignificant because of obesity and anemia. A small number of adult patients with tetralogy of Fallot may present with hypertension. The left thoracic precordial region is often elevated, and in some cases, elevated pulsations in the precordial region are seen. A systolic jet murmur is present between the third and fourth intercostal spaces at the left sternal border. The absence of a murmur in rare patients often indicates severe obstruction or combined pulmonary atresia. There is a single second heart sound in the pulmonary valve region. A double-phase continuous murmur can sometimes be heard at the corresponding site in the presence of a thick unclosed ductus arteriosus or a side branch of the corporal pulmonary artery.