Abstract OBJECTIVE: To summarize the experience of inlay treatment of children with septal intact pulmonary atresia and severe pulmonary stenosis near atresia with pulmonary valve puncture balloon dilation under open chest non-extracorporeal circulation. METHODS: We retrospectively analyzed 11 cases of septal intact pulmonary atresia treated with pulmonary valve puncture balloon dilatation from 2009.01 to 2011.02. We recorded the surgical data and postoperative monitoring data, the average age was 50 days, the average weight was 4.3 kg, the minimum weight was 2.7 kg, and the minimum age was 4 days. Results: 9 cases of septal intact pulmonary atresia, 2 cases of severe pulmonary stenosis close to atresia, fair right ventricular development, tricuspid valve Z value greater than -2, the whole group was dilated by open thoracotomy non-extracorporeal puncture balloon of pulmonary valve, and there was no death in the operation. Two children had low heart rate and one had delayed chest closure 3 days after surgery; there was no in-hospital death. At a mean follow-up of 3 months, all children still had mild-moderate pulmonary stenosis, and one child underwent postoperative right ventricular outflow tract patch enlargement for postoperative pulmonary stenosis. Conclusion: Open-chest puncture balloon dilatation of the pulmonary valve can avoid the disadvantages of traditional surgical correction requiring ventriculotomy and intraventricular myotomy, which have a large impact on cardiac function; it can eliminate the impact of extracorporeal circulation on cardiac function in conventional surgery, as well as avoid complications from catheterization, and improve the safety and success rate of the operation. Pulmonary atresia with intact septum (PAIVS) is a complex neonatal precordial disease that requires emergency care shortly after birth and has a high surgical morbidity and mortality rate. With the development of medical science, the treatment of PAIVS is different, and how to intervene in the early stage of the disease has become a more important focus, with traditional surgery and catheter intervention becoming the two main approaches, but there is no uniform treatment principle due to their respective advantages and disadvantages. This paper aims to summarize the effectiveness and experience of mosaic therapy in the treatment of PAIVS through a retrospective analysis of children with PAIVS. General data Children with pulmonary atresia with intact septum and severe pulmonary stenosis (near atresia) were admitted to our center from January 2009 to February 2011. Eleven children were enrolled, including 8 neonates and 3 infants, with a mean age of 50 days, a mean weight of 4.3 kg, a minimum weight of 2.7 kg, and a minimum age of 4 days. The balloon was dilated by introducing the guiding wire and sheath, and the balloon was repeatedly dilated several times under the guidance of TEE, and the antegrade flow was checked by TEE. All children’s surgical data were recorded, including surgical technique and perioperative monitoring data, such as ventilator use time, monitoring time and postoperative complications, and the children were followed up once in 3 months after surgery. Results Preoperatively, all children had a tricuspid valve Z value greater than -2, their right ventricles had 3 parts (i.e., inflow tract, trabecular section, and outflow tract), no significant abnormalities in the coronary arteries, and no right ventricle-dependent coronary circulation, and all children were given prostaglandin E1 preoperatively, and 5 of them were given preoperative ventilator-assisted respiratory maintenance to correct metabolic acidosis, and preoperative SPO2 65% ± 5% preoperative ultrasound showed that all children The children had a common pulmonary artery trunk. There was no death in the early stage of surgery, and the survival rate was 100%. There were no adverse events related to direct visual mosaic therapy. 2 children had low cardiac output, one case improved after administration of peritoneal dialysis, postoperative SPO2 reached 90%±4%, only one child was given BT surgery due to hypoxia, the child was on ventilator for 72 hours±4 hours on average, CICU stay was 6 days±1.4 days, one case PDA closed on its own. Postoperative follow-up children all currently maintain mild to moderate pulmonary artery stenosis. After one week of postoperative follow-up, the children were followed up once every 3 months on average, with a mean follow-up time of 8 months±3 months. One of the children had a right ventricular outflow tract patch enlargement in 6 months after mosaic treatment because the postoperative follow-up ultrasound showed a maximum transvalvular flow velocity >5m/s. The flow velocity gradually decreased after surgery, and the current recovery is good with a differential pressure <20mmHg. All children currently have mild to moderate pulmonary stenosis and are growing relatively well. The RV on the left is the right ventricle, the MPA is the main pulmonary artery, and the PV shows pulmonary valve atresia on the right, which shows the flow through the pulmonary valve after puncture balloon expansion. Early literature reported a mortality rate of more than 40% and a long-term survival rate of less than 25% [1], but through advances in medical technology, the mortality rate of PAIVS has decreased from 56% to 16% [2]. The treatment of this disease has been a challenge, and the choice of treatment and surgical procedure is controversial [3, 4]. Conventional PAIVS starts with keeping the arterial duct open to prevent severe hypoxia and metabolic acidosis, and the surgical approach is chosen according to the tricuspid valve, right ventricular development and whether the child is coronary right ventricular dependent. If the child has poor right ventricular and tricuspid valve development or is right ventricular dependent coronary artery, a single ventricular repair Fontan route or a hemi-ventricular repair is preferred. The choice of single or biventricular repair route has also been reported based on the tricuspid Z value, the right and left ventricular length ratio, and the ratio of the mitral and tricuspid annuli [5]. The survival rate of children with pulmonary atresia has increased in recent years through advances and developments in medical technology, but the 5-year survival rate for surgical treatment is still only 60% [6]. In 1938, Gross et al. successfully ligated the arterial catheter, and in 1966, Rashkind et al. first applied a balloon septal stoma with a balloon catheter at the head end, which can be considered as the ancestor of surgery and intervention, while in 2002, Hjortdal successfully combined surgical techniques and interventional therapy, pioneering hybrid therapy. The first of its kind. With the support of real-time imaging, mosaic therapy can shorten or avoid the time of extracorporeal circulation, and is characterized by low trauma, timely treatment, and high accuracy, which is especially suitable for conditions where cardiac catheterization or surgical techniques alone cannot achieve satisfactory results. The proposal and application of inlay therapy has changed the traditional treatment paradigm of precordial surgery. The controversy of PAIVS treatment lies mainly in the choice of early treatment methods. Improving hypoxia, inducing progressive development of the right ventricle and the provision of adequate blood flow by the pulmonary artery are the main issues before the surgeon. Traditional procedures such as right ventricular outflow tract patch enlargement and body-pulmonary bypass surgery have been maintained for quite some time in the treatment of pulmonary atresia, and Greenwold [7] of Mayo Clinic Hospital described the case staging of PAIVS and suggested that pulmonary valvotomy is the more appropriate procedure in the type with better right ventricular development. Since Qureshi and colleagues reported transcatheter balloon dilation for PAIVS with laser assistance in 1991, transcatheter balloon dilation has gradually become the applied method to unblock the right ventricular outflow tract in the treatment of pulmonary artery atresia. In the neonatal statistics, it was reported that the in-hospital mortality rate decreased from 22% to 10% from 1982-1986 to 2002-2006, with 18% mortality in patients with right ventricular outflow tract evacuation and only 3 deaths in 225 children with balloon-expandable pulmonary valvuloplasty. While catheter interventions are gradually gaining acceptance because of their low invasiveness, avoidance of extracorporeal circulation, and low mortality, they also have some problems. The efficiency of laser-guided pulmonary flap dissection alone has been reported to be 67% [9], but laser transmitters and goggles are more expensive. In neonates or infants with severe symptomatic pulmonary valve stenosis or aortic constriction, percutaneous interventions are often associated with complications such as rupture, perforation, dissection and papillary muscle or tendon injury, or even material dislodgement, due to the pathway and vessel size [10]. Jou-kou Wang [12] performed transcatheter pulmonary valvotomy in 35 infants with PAIVS and found that although the procedure was effective in pulmonary valvotomy, right ventricular systolic pressure decreased from 119 ± 22 to 54 ± 13 mmHg because of postoperative hypoxia and right ventricular funnel stenosis. partial stenosis, seven of the children required right ventricular outflow tract patch enlargement and the other two required body-lung bypass surgery. The mortality and complications caused remain to be noted, and four children in this group did not complete the intervention due to pericardial tamponade and other reasons. And one died early due to pericardial tamponade. Intraoperative supraventricular tachycardia can also occur with laser with pulmonary valve balloon dilation. Also, some articles have reported that although a proportion of children can be relieved by conventional subcatheter pulmonary arteriotomy, the majority of children with right ventricular dysplasia still require body-lung shunts to relieve hypoxia [13]. The use of intraoperative percutaneous balloon dilation or stenting avoids these disadvantages, as well as the effects of extracorporeal circulation. In arterial catheter-dependent conditions such as PAIVS, especially in cases where the pulmonary valve is fibro-membranous atresia, the valve is perforated by applying a guided wire hard tip, radiofrequency ablation or laser to reconstruct the connection between the pulmonary artery and the right ventricle, and then a balloon catheter is applied to dilate the pulmonary valve. If the arterial oxygen saturation is unsatisfactory, an arterial catheter stent can be placed via the common pulmonary artery to provide additional pulmonary blood flow. Otherwise, the arterial catheter can be ligated at the same time. Puncturing the balloon to dilate the pulmonary valve in an open chest situation can avoid the disadvantages of traditional surgical correction requiring ventricular incision and intraventricular myocardial bundle dissection, which have a large impact on cardiac function; it can eliminate the impact of extracorporeal circulation on cardiac function in conventional surgery, as well as avoid complications arising from catheter pulmonary arteriotomy, and improve the safety, accuracy, and success rate of the operation [14]. In our group of cases, no intraoperative myocardial dissection, no extracorporeal circulation, relatively good prognosis for postoperative recovery, no postoperative death, short operating room stay, and postoperative follow-up are all aspects that show that mosaic therapy is more effective in the treatment of PAIVS. This is a retrospective study of a small sample, and the indications for mosaic therapy, the need for simultaneous BT surgery, and the choice of postoperative single and double ventricular repair may require a larger study and follow-up. Of course, the choice of intraoperative percutaneous balloon dilatation treatment is highly dependent on the degree of right ventricular development of the patient, and the correct assessment of the degree of right ventricular development is particularly critical. Tricuspid Z values and right-to-left ventricular area ratios are very relevant for right ventricular cavity assessment, and pulmonary valve Z values are predictive of the effectiveness of pulmonary valvotomy outcomes, with tricuspid Z values >-0.1, pulmonary valve Z values >-4.1, and right-to-left ventricular ratios >0.65 being used to assess the effectiveness of interventional pulmonary valvotomy alone. When the patient has a tricuspid Z value <-0.8, a pulmonary Z value <-4.2, and a right ventricular to left ventricular ratio <0.54, intraoperative percutaneous balloon dilatation can be performed with simultaneous right ventricular outflow tract patch enlargement or BT shunt. In summary, intraoperative percutaneous balloon dilatation for PAIVS is more straightforward than simple cardiac catheterization for pulmonary valvotomy, and the accuracy, safety, and operability of the procedure far exceed those of transinguinal or internal jugular vein. This makes the procedure simple, safe, and especially suitable for neonates. It provides good conditions for further second-stage correction of the child.