Assessing fetal circulatory alterations in preeclampsia: The role of caval aortic index and left brachiocephalic vein diameter.

Objective

The primary objective of this study is to compare the fetal caval aortic (IVC/Ao) index and left brachiocephalic vein (LBCV) diameter between pregnancies with preeclampsia (PE) and healthy controls. The study also assesses their association with disease severity and perinatal outcomes.

Methods

In this prospective case-control study, 60 pregnancies complicated by PE were compared with 60 gestational age-matched healthy controls. The fetal IVC/Ao index, LBCV diameter, Doppler parameters, and perinatal outcomes were assessed. Subgroup analyses in the PE group considered admission blood pressure, symptoms, proteinuria, and neonatal outcomes.

Results

The PE group had a lower IVC/Ao index and larger LBCV diameter (P = 0.043 and P = 0.025, respectively). The umbilical artery pulsatility index was higher (P = 0.008), and the cerebroplacental ratio was lower (P = 0.005) in PE. Smaller ascending aorta diameter was noted in severe hypertension (P = 0.042), and the LBCV diameter was greater in symptomatic cases (P = 0.007). Proteinuria ≥+2 was associated with earlier delivery (P = 0.014) and lower birth weight (P < 0.001). Neonates admitted to the neonatal intensive care (NICU) had lower fetal inferior vena cava (IVC) diameters and lower IVC/Ao indices. An IVC/Ao index cutoff of 0.79 was associated with NICU admission, demonstrating moderate discriminatory performance (sensitivity 72.2%, specificity 73.8%, area under the curve = 0.762; 95% confidence interval 0.61-0.90; P = 0.001).

Conclusion

Fetuses of PE pregnancies had decreased IVC/Ao index and enlarged LBCV diameter, potentially linked to impaired fetal hemodynamics. The IVC/Ao index might help identify pregnancies complicated by PE that are at increased risk of NICU admission.