Doppler echocardiographic evaluation of right ventricular diastolic function in children

Right ventricular diastolic function was evaluated by flow velocity pattern in the right ventricular inflow tract by means of pulsed Doppler echocardiography. Traditionally used to evaluate this function are peak velocities obtained during early diastole (peak E wave) and during atrial contraction (peak A wave), their ratio (peak E/A ratio), and the deceleration half-time. We conducted pulsed Doppler echocardiographic studies of right ventricular inflow and outflow patterns in 171 children (105 normal children and 66 children who were undergoing total surgical repair of congenital heart defects without sequelae). Results showed that summation flow was present in the right ventricular inflow tract in 43 (25%) of the 171 subjects, which made it difficult to separate the peak E wave from the peak A wave. We noted the presence of antegrade late diastolic flow (DW) in the right ventricular outflow tract of all subjects. DW, measured in 121 subjects in whom both E and A waves were detected in the right ventricular inflow tract, showed a highly significant correlation (p < 0.0001) with A waves in the right ventricular inflow tract. The ratio of DW to right ventricular outflow tract velocities during systole (SW) showed a highly significant (p < 0.0001) correlation with E/A ratio. When evaluating right ventricular diastolic function by pulsed Doppler, especially in children, the analysis of right ventricular outflow tract patterns is helpful in addition to that of inflow tract patterns. The DW and DW/SW ratio may present good alternatives to traditional parameters in children.