Prenatal diagnosis of major aortopulmonary collateral arteries (MAPCA) in fetuses with pulmonary atresia with ventricular septal defect and agenesis of ductus arteriosus

Objective: The aim of this study was to describe the prenatal diagnosis of Major Aortopulmonary Collateral Arteries (MAPCAs), and to present a systematic ultrasound method for evaluating lung vascularity in fetuses with pulmonary atresia with ventricular septal defect (PAVSD) and agenesis of ductus arteriosus (DA). Method: This retrospective study evaluated fetuses diagnosed with PAVSD with agenesis of DA, for the presence of the MAPCAs anomaly. Fetal pulmonary vasculature was investigated by 2D and 4D Spatio Temporal Image Correlation (STIC) technology using High Definition Color Doppler. Results: Over a 10 year period, six fetuses were diagnosed with MAPCAs. Prenatal diagnosis was made between 17 w 6 d and 28 w 4 d in five fetuses, with the sixth diagnosed at 37 w 6 d. All six had PAVSD with agenesis DA, four exhibited pulmonic atresia without any arterial outflow, while two fetuses presented with absent left pulmonary artery, and a miniscule right pulmonary artery. In five cases, the parents elected to terminate the pregnancy and the last, although born alive, did not survive an attempt at restorative surgery and died at the age of 5 months. Postnatal CT angiography imaging of this case revealed the subclavian origin of the MAPCAs. Chromosomal micro array analysis of the amniotic fluid revealed that five of the six fetuses were normal and one was lost to follow up. Conclusion: MAPCAs should be investigated in cases of PAVSD with agenesis DA. A meticulous ultrasound evaluation using 2D and 4D STIC can permit the prenatal diagnosis of this anomaly and provide the parents with the opportunity for prenatal consultation.