Fig. 1

Measurements of the fetal cardiac parameters. In the right ventricular outflow tract view, pulmonary valve annulus is measured from hinge point to hinge point at the location of maximal expansion during peak systole (A, arrow). In the three-vessel view, the right pulmonary artery is measured at the proximal part of its bifurcation (B, arrow). In the left ventricular outflow tract view, the aortic valve annulus is measured from hinge point to hinge point at the location of maximal expansion during peak systole (C, arrow). In the ductal arch view, pulmonary valve peak systolic velocity is measured at the level of the pulmonary valve using pulsed Doppler (D). In the aortic arch view, the descending aorta is measured at the level of the diaphragm (E, arrow)