The Effect of Fetal Intrauterine Blood Transfusion on Ductal Arterial Blood Flow Velocity and Cardiac Output Changes in Fetuses with Rhesus Alloimmunization-Related Anemia.

BACKGROUND

Echocardiographic indicators may be useful as an alternative method to determine the appropriate time for intervention, especially when Doppler assessment of the middle cerebral artery peak systolic velocity (MCA-PSV) is inconclusive. In this study, arterial duct blood flow and cardiac output of fetuses with Rh alloimmunization-related anemia were compared before and after intrauterine transfusion (IUT).

METHODS

Fifty intrauterine blood transfusions were performed on anemic fetuses in this study. All cases were attributed to Rh alloimmunization, detected with MCAPSV Doppler ultrasound imaging assessments. They all underwent intrauterine blood transfusion and echocardiographic assessments a day before and 24 hr after the procedure. The measured cardiac indices included the velocity time integral (VTI) of the aortic and pulmonary valves, the ductus arteriosus acceleration-to-ejection time (AT/ET) ratio, and the MCA-PSV. Analyses were performed in SPSS v24 (p<0.05) using paired t-tests for mean differences and Pearson's correlation for associations between continuous variables.

RESULTS

Aortic and pulmonary valve VTI, MCA-PSV, and ductus arteriosus AT/ET ratio significantly decreased after intrauterine blood transfusion (p<0.001). The aortic valve VTI and ductus arteriosus accurately detected anemia, with areas under the receiver operating characteristic (ROC) curve of 99.9% and 98.9%, respectively.

CONCLUSION

All the measured parameters showed significant changes after intrauterine blood transfusion. Aortic valve VTI and ductus arteriosus AT/ET ratio seem to have the highest accuracy in detecting anemia. Echocardiographic assessment can be beneficial in defining the appropriate time for intrauterine blood transfusion in cases where MCA-PSV is inefficient.