Tricuspid annular plane systolic excursion measured by spatio-temporal image correlation-M mode in evaluation of right ventricular systolic function in normal fetuses

Objective: To quantitatively study of right ventricular systolic function in the normal second and third trimester fetuses by tricuspid annular plane systolic excursion (TAPSE) measured by spatio-temporal image correlation-M (STIC-M) mode. Methods: TAPSE was successfully measured by using conventional M-mode echocardiography and STIC-M mode on 170 normal second and third trimester fetuses and each gestation age (GA) had 10 fetuses. The two methods of measurement were compared. Meanwhile the correlations between TAPSE and other parameters such as GA, estimated fetal weight (EFW), tricuspid early diastolic peak E-wave velocity (E), tricuspid late diastolic peak A-wave velocity (A) were analyzed. Results: No significant difference was found in measures obtained with conventional M mode and STIC-M mode. TAPSE measured by STIC-M mode was correlated with GA, EFW, E and A significantly (all P<0.001). Conclusion: In normal second and third trimester fetuses, TAPSE increases with the growth of GA, EFW, and it has strong correlation with E and A. TAPSE measured by STIC-M mode is almost not affected by fetal position, and it may become a new promising modality to evaluate right ventricular function simply and accurately.