The Differential Diagnosis of Double Aortic Arch and Right Aortic Arch with Mirror-Image Branches in the Fetus: A Potential Novel Method

The objective of this study was to explore a new method for the differential diagnosis between fetal double aortic arch (DAA) and right aortic arch with mirror-image branches (RAA-MB). Clinical data and prenatal echocardiographic features of the DAA (n = 22) and RAA-MB (n = 65) confirmed by postnatal or autopsy findings were analyzed retrospectively. The angles between the two aortic arches in the DAA group and between the right aortic arch and the mirror branch were measured. The differences between the two groups and differential diagnosis value of the angles were compared and analyzed based on the receiver operating characteristic curve. The proportion of left-sided ductal arteriosus (100%) was higher in the DAA group than that (32.3%) in the RAA-MB group, (P < 0.05). The proportion of conotruncal anomalies is higher in the RAA-MB group (64.6%) than in the DAA group (18.2%) (P < 0.05). There was a significant difference in the angles between the groups (DAA: 50.3° ± 8.3° vs. RAA-MB: 82.9° ± 13.8°) (P < 0.01). When the cutoff value was 62.8°, the sensitivity and specificity of the differential diagnosis were 95.5% and 96.9%, respectively. Distinguishing the angle measurement between DAA and RAA-MB is helpful in prenatal prognosis. We recommend a cutoff value of 62.8°.