Figure 2: Relationship between gestational age and tissue Doppler velocities and M-mode at lateral mitral annulus. The tissue Doppler imaging early (E') and late (A') diastolic and systolic (S') velocities (panels a-c), E'/A' ratio (panel d) as well as mitral annular peak systolic excursion (panel e) increased progressively with gestational age. The E/E' ratio (panel f) showed a negative correlation and decreased with increasing gestation