Tissue Doppler Imaging of Atrioventricular Annulus in Normal Fetuses

Objective To assess the feasibility of tissue Doppler imaging (TDI) in normal fetuses,and to analyze peak velocities of the mitral annulus (MA) and the tricuspid annulus (TA) in different gestational ages.Methods Tissue Doppler images were obtained in 67 normal fetuses between the 17th and the 41th week of gestation. The subjects were divided into three age groups. Measurements included peak velocities of MA and TA during systole,early diastole and late diastole,and the ratio of peak velocities during early diastole to that during late diastole (Ea/Aa).Results Systolic and early diastolic peak velocities and Ea/Aa of both MA and TA increased significantly with the increasing of gestational age,but the correlations between late diastolic data and gestational age were weaker. The peak velocities of MA were significantly lower than those of TA (P0.01).In both MA and TA,there were significant relation between Ea/Aa and pulsed Doppler E/A (P0.01).Conclusion TDI is useful in assessing the motion of MA and TA in fetuses and observing age-related alterations.TDI is a new method for assessing the fetal cardiac function.