Background Compromise of right heart function is an important feature of many forms of
congenital heart disease, and right atrial (RA) pressure is clinically relevant. Inferior vena
cava (IVC) diameter and inspiratory collapse are indices of RA pressure, but pediatric data
are lacking. Methods RA measurements, systemic venous diameters, and Doppler filling
fractions were prospectively investigated in healthy volunteer children and adolescents. The
IVC was measured in its long axis just above the junction with the hepatic veins in the …