Velocity vector imaging for evaluation of fetal vertical function throughout gestation

Aim: Velocity vector imaging (VVI) is a speckle-tracking ultrasonographic assessment technique used to evaluate myocardial function. However, VVI values show wide deviations. This study aimed to clarify the significance of serial VVI values for assessing fetal cardiac function. Methods: Echocardiographic images of 50 fetuses (normal: n = 29, fetal growth restriction [FGR]: n = 21) were obtained in the four-chamber view during the second and third trimester. VVI images were analyzed for longitudinal velocity, strain, and strain rate in the global and segmental walls of the left ventricle (LV) and right ventricle (RV). Results: Global longitudinal velocity (GLV) of the LV and RV during the third trimester did not significantly differ between FGR and normal fetuses. LVd and RVs appeared to be low in HDP cases, although there were no significant differences compared to no HDP cases. Eighty-two serial images obtained from 13 normal singleton fetuses revealed increased systolic GLV of the LV and RV, increased diastolic GLV in 10 cases, and increased longitudinal velocity in the basal and middle free wall of both the LV and RV. Conclusions: The evaluation of fetal ventricular function using VVI revealed that GLV increases throughout gestation.