Pulmonary atresia and ventricular septal defect: How accurate is the fetal echocardiography, and do the major aortopulmonary collateral arteries matter?

OBJECTIVE: To assess the accuracy of prenatal echocardiography in defining pulmonary vasculature in pulmonary atresia with VSD (PAVSD). The second aim is to compare the perinatal and postnatal outcomes of different pulmonary blood supply types. STUDY DESIGN: The cases prenatally diagnosed with PAVSD between 2017 and 2022 in a single tertiary fetal medicine center were identified on the electronic database. Fetal echocardiography reports and images were reviewed retrospectively. Postnatal outcomes were acquired from the hospital records of relevant pediatric cardiology and cardiovascular surgery clinics. Fetal echocardiography results were compared with postnatal results. Perinatal and postnatal outcomes were compared between the different pulmonary vascular supply types. RESULTS: Among the 24 PAVSD cases, six were diagnosed with major aortopulmonary collateral arteries (MAPCA) dependent, eleven were diagnosed with ductus arteriosus (DA) dependent pulmonary supply, and seven were diagnosed with double pulmonary supply (MAPCA + DA) on prenatal echocardiography. Seventeen cases were live-born and have undergone postnatal investigations. Fetal echocardiography was 88.2% accurate about the type of pulmonary supply. The accuracy of fetal echocardiography regarding pulmonary vascular anatomy was 82.3%. Postoperative survival was 69.2%. Mortality before surgery and postoperative survival did not differ between pulmonary supply groups. Survival was impaired by the extracardiac anomalies. The need for early interventions was significantly higher in the DA group. CONCLUSION: Pulmonary vascularization in PAVSD can be defined precisely on fetal echocardiography. The source of pulmonary blood supply does not impact postnatal short-term outcomes significantly but it impacts the management. The associated anomalies highly contribute to postnatal mortality.

Riociguat can ameliorate bronchopulmonary dysplasia in the SU5416 induced rat experimental model.

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a chronic lung disease in premature neonates. Classical BPD is caused by hyperoxia and high-pressure mechanical ventilation, whereas BPD in recent era is caused by impaired pulmonary angiogenesis and alveolarization in extreme prematurity. Although sildenafil was reported to be effective in a hyperoxia-induced rat BPD model, several clinical trials could not demonstrate any significant improvement in the respiratory statuses of BPD infants. Riociguat is a soluble guanylate cyclase stimulator that increases cyclic guanosine monophosphate activity in a nitric oxide independent manner. However, a beneficial effect in BPD has not been established yet. METHODS AND RESULTS: We established BPD model in rats by injection of SU5416 on day 1 followed by maintenance under normoxia, which resulted in oversimplified alveoli, sparse pulmonary capillary vessels, severe pulmonary hypertension, and growth retardation, which mimicked the features observed in recent clinical management of BPD. We administered riociguat from day 10, when BPD rats exhibited growth retardation. Histological analyses demonstrated that riociguat treatment significantly but partially ameliorated lung alveolarization, vascularization, and pulmonary hypertension. However, the survival rate was not significantly improved by riociguat treatment. CONCLUSIONS: Riociguat could ameliorate pulmonary alveolarization, vascularization, and hypertension in the SU5416 induced BPD rat model, but could not improve the overall survival.

Chinese expert consensus on surgical treatment of congenital heart disease (3): pulmonary atresia with ventricular septal defect / 中国胸心血管外科临床杂志

@#Pulmonary atresia with ventricular septal defect (PA/VSD) is a complicated congenital heart defect. The consensus of Chinese experts is developed based on the evidence-based data and expert opinions provided by the literature. Tchervenkov classification (A, B and C, three types) is adopted. Echocardiography is preferred to assess the abnormalities of the heart, physiological function and pulmonary artery development, but it is not absolutely accurate for the evaluation of collateral vessels. Furthermore, multi-row CTA can confirm the development of the native pulmonary artery, the number, origin and morphological characteristics of collateral vessels. Additionally, angiography provides more details of the number, origin and distribution of collateral vessels. Genetic testing is important to understand the genetic etiology and to determine the prognosis. After definite diagnosis, treatment plan is made according to the classification and clinical manifestations. Pulmonary artery flow is arterial duct dependent for Type A and surgical treatment is usually performed within 6 months. But patients with severe hypoxia were treated during neonatal period. The strategy for type B/C is more complex. Severe hypoxemia may occur in infants with type B PA/VSD and decreased pulmonary flow, and systemic to pulmonary artery shunt should be performed during neonatal or early infant period, complete repair following after good pulmonary arterial development. On the other hand, for patients with over circulating pulmonary flow, primary repair is perform with 3~6 months for congestive heart failure. For patients with balanced pulmonary flow and repairable condition, one-stage complete repair can be performed in infancy stage. Otherwise, palliative systemic to pulmonary artery shunt or right ventricle to pulmonary artery shunt should be first, and second-staged complete repair or pulmonary arterial development promotion is adopted according to following assessment. The surgical option for type C PA/VSD should be discreet. Pulmonary arterial flow study is demanded after unifocalization to decide to close the VSD completely or not. Close follow-up after operation is imperative and cardiac catheterization is perform to reveal the pulmonary artery and collateral vessels if necessary and dilates the site of stenosis.