Normal values of left and right ventricular function measured by ?mode, pulsed doppler and Doppler tissue imaging in healthy term neonates during a ?year period

摘要

Background: The measurements of left and right ventricular functions change after birth due to the influence of several hemodynamic changes upon the immature myocardium. Aim: The aim of this study was to investigate the changes in left (LV) and right ventricular (RV) functions of healthy term newborns using conventional and Doppler echocardiography during a 1?year period. Subjects and methods: Fifty healthy term newborns were examined prospectively on the first day, 3-4, 6-7, 9-10 and 11-12. months of their lives by ?mode, pulsed Doppler (PD) and Doppler tissue imaging techniques (DTI). PD velocities were obtained from mitral and tricuspid valves while DTI velocities were obtained from the lateral annuluses of atrioventricular valves. Results: EF and FS did not change significantly by time. Early (E) flow velocity and early myocardial (Em) velocity were higher than late (A) flow velocity and atrial systolic (Am) velocity for LV, while A and Am velocities were higher than E and Em velocities for RV, respectively during the study period. E, A, Em, Am, Sm velocities and Em/Am ratios increased while E/Em ratios decreased significantly by time (P<0.05) for both ventricle. However, E/A ratios of LV and RV did not change significantly by time. Myocardial performance index (MPI), obtained by PD for RV and by DTI for LV, decreased significantly by time (P<0.05) and these DTI values were higher than PD values during the study period. Conclusions: Due to hemodynamic and maturation change of myocardium PD and DTI velocity changes took place during the first year of life which reflects differences in ventricular adaptation.