Objectives
The aim was to compare the indices between right (RV) and left (LV) ventricle obtained by tissue Doppler imaging (TDI) and evaluate the relationship between them in fetuses with structurally normal heart.
Methods
This was a cross-sectional study on 20 normal fetuses between 18 and 38 weeks of gestation. Two-dimensional echocardiography was used to examine fetal anatomy. TDI was used to assess diastolic velocities (peak velocity of early (E’) and late (A’) diastolic filling) and peak systolic velocity (S’) at the lateral margins of both mitral (MVa) and tricuspid (TVa) annulus. The RV and LV Tei indices were calculated.
Results
A total of 30 echocardiographic examinations were performed. The mean gestational age was 32.1 ± 4.3 weeks. Among the peak velocity indices obtained by TDI, MVa-S’ (r = 0.62), TVa-S’ (r = 0.56), MVa-E’ (r = 0.68), and TVa-E’ (r = 0.57) showed positive correlation with gestational age, while neither MVa-A’ nor TVa-A’ correlate with the age. Negative correlation was demonstrated only between gestational age and LV-Tei index (r = 0.36). Comparing the indices obtained from LV to that from RV, a significant positive correlation was present only between MVa-S’ and TVa-S’ (r = 0.53).
Conclusions
In the normal fetus, longitudinal myocardial performance in systole appears to be developed in proportion to the gestational age in contrast to that in diastole. Additionally, systolic performance in LV being correlated to that in RV may suggest that proportional development in the both ventricle is the must in normal fetus.