Clinical Utility of Fetal Magnetic Resonance Imaging in Tetralogy of Fallot With Absent Pulmonary Valve

Abstract

A 28-year-old woman was referred to an outside center at 20 weeks’ gestation for fetal echocardiogram, which revealed the diagnosis of tetralogy of Fallot with absent pulmonary valve. There were an anterior malalignment-type ventricular septal defect, overriding aorta, and severe pulmonary insufficiency in the setting of severely dysplastic, rudimentary pulmonary valve leaflets. The patient presented to our center at 31 weeks for follow-up evaluation and delivery management planning. Fetal echocardiogram confirmed the diagnosis. The main and branch pulmonary arteries were markedly dilated (Figure 1A and 1B and Movies I and II in the online-only Data Supplement), and there was no ductus arteriosus. The cardiac silhouette was shifted leftward with a cardiac axis of 112°, deviating significantly from a normal fetal cardiac axis of 45° (Figure 1C). The left lung appeared small and diffusely hyperechoic relative to the right lung, suggesting atelectasis or consolidation. Figure 1. A , Fetal echocardiogram image demonstrating massively dilated main and branch pulmonary arteries. Arrow indicates the rudimentary pulmonary valve. LPA indicates left pulmonary artery; and RPA, right pulmonary artery. B , Sagittal fetal echocardiogram image demonstrating a cross section of the massively dilated right pulmonary artery. Ao indicates aorta. C , Axial echocardiographic view of the fetal chest demonstrating marked leftward deviation of the cardiac axis in the setting of right lung overexpansion and left lung hypoplasia vs compressive volume loss. The angle demonstrates a cardiac axis of 112°. Note that the left lung appears more echo-bright compared with the right lung. LL indicates left lung; LV, left ventricle; RL, …