Fig. 6

Proximal aortic atresia on three-vessel and tracheal view. a Schematic drawing. b Ultrasound images. It showed an asymmetric “V” sign. Hypoplasia of aortic arch and retrograde flow of ductus arteriosus from the pulmonary artery into the aorta could be detected. ARCH: aortic arch; PA: pulmonary artery; PDA:patent ductus arteriosus