Effect of sample volume location on pulsed Doppler diastolic flow parameters in newborn infants.

Pulsed Doppler echocardiography was used to measure parameters of left and right ventricular diastolic filling from both the valve annulus and valve leaflet tips in 36 newborn infants. Absolute values for E and A velocities were 13% higher at the mitral leaflet tips and 10%-18% higher at the tricuspid tips than at the respective valve annulus. Similarly, values for diastolic velocity-time integral measurements were 6%-18% higher when sampling was performed at the leaflet tips. With the exception of the transtricuspid velocity ratio, E/A ratio values were not affected by sample volume location. Doppler sample volume location can influence velocity and velocity-time integral measurements in newborn infants. Attention to consistent sample volume location is important in serial or comparative studies.