Evaluating fetal pulmonary vascular development in congenital heart disease: a comparative study using the McGoon index and multiple parameters of fetal echocardiography.

Objectives: The purpose of this study was to evaluate the value of MGI and multi-parameter in the assessment of different pulmonary circulation blood volumes in congenital heart disease.

Methods: This study included 350 fetuses categorized into two groups: Normal group consisted of 258 fetuses with no discernible abnormalities through echocardiography as control Group A; Abnormal group with abnormal echocardiogram, including Group B of 71 fetuses with decreased pulmonary blood flow or pulmonary atresia and Group C of 21 fetuses with reduced or detached aortic blood flow.

Results: The MGI and Z-scores were measured and compared among these groups. Significant variations were noted in the aortic outflow Z-scores (AO-Zs) (p<0.01), pulmonary artery (PA) (p<0.01), PA Z-scores (PA-Zs) (p<0.01), PA/AO (p<0.01), right PA (p<0.01), and MGI (p<0.01) among the three groups (all p<0.05). Among fetuses with decreased pulmonary blood flow or pulmonary atresia, PA, PA-Zs, and MGI in fetuses with reverse DA flow perfusion were lower than those in the DA forward perfusion group.

Conclusions: Fetal echocardiography, incorporating the MGI and multi-parameter, not only allows for the evaluation of pulmonary blood flow and pulmonary vascular development of the fetus but also enables the observation of changes in pulmonary blood flow and MGI development across different gestational weeks.