In the presence of fetal cardiomegaly, when there is no cardiac malformation or dysfunction, systemic or pulmonary arteriovenous malformations that may cause volume loading should be sought. We aimed to present a fetus who had cardiomegaly and left pulmonary artery-left atrial fistula and who underwent transcatheter closure in the early postnatal period.

23-week fetus referred because of severe cardiomegaly on screening obstetric ultrasonography. Fetal echocardiography revealed fistulous connection between dilated left pulmonary artery and left atrium with high velocity continuous flow at the left atrial orifice of fistula and retrograde flow from the ductus arteriosus to the pulmonary artery. Initially, the fetus followed by one-to-two weeks intervals for fetal heart failure and hydrops fetalis. Pregnancy was uneventful and the baby was born by caesarean section at 37 weeks, and oxygen saturation level was 95 %. Transthoracic echocardiography confirmed the prenatal diagnosis of a fistula between the left pulmonary artery and the left atrium (CTA showed left lung aplasia. Transcatheter closure was performed from antegrade route with Amplatzer Piccolo® Duct Occluder due to hypoxaemia. The baby showed normal growth and development at 15 months of ageThere is no pulmonary hypertension during the 15-month follow-up.

Pulmonary artery-to-left atrial fistula is a rare anomaly and is frequently described between the right pulmonary artery and the left atrium. Presentation of age depends on the size of the fistulous connection. Patients with large connections are presented in fetal age with cardiomegaly and heart failure or presented in early infancy with profound cyanosis. Although lung hypoplasia has been reported in patients with pulmonary artery-to-left atrial fistula/connection lung aplasia has never been reported in these patients. Surgical or transcatheter closure can be achieved successfully in these patients at neonatal period or early infancy like in our case.