EP09.61: New insights in the management of aberrant right subclavian artery: is it a real risk factor for genetic disorders? Analysis of postnatal outcome

To evaluated the association between isolated aberrant right subclavian artery (ARSA) with genetic abnormalities and postnatal symptomatology. Retrospective, descriptive study of all fetuses diagnosed with ARSA at midtrimester in a hospital in Barcelona between 2007-2023. Cases of ARSA were divided into isolated ARSA and non-isolated ARSA (with cardiac or extracardiac abnormalities and/or soft markers). All live newborns underwent examination by a pediatrician/pediatric cardiologist prior to hospital discharge. For each case, a combination of data was compiled from our electronic clinic history. In cases where clinical questionnaires were unavailable, information was obtained through direct communication with the parents. The measured variables are presented as means ± standard deviation and categorical variables are presented as numbers and percentages. 154 fetuses were diagnosed with ARSA: 116 (75.3%) were isolated and 38 (24.7%) were associated with other structural anomalies (9 cardiac defects, 17 extracardiac defects and 10 soft markers). In 27.3% (85% isolated ARSA) cases non-invasive prenatal test with cell-free DNA was performed, yielding 97.6% low risk results. Additionally, 15.6%, 79% non-isolated ARSA) opted for genetic evaluation. Genetic abnormalities were detected in 4 fetuses: 2 trisomy 21 and 2 22q11 deletion. All fetuses with genetic anomalies had associated structural defects (atrioventricular defect, duodenal atresia, right ductus arch, talipes equinovarus, small fetal thymus, intrauterine growth retardation). Overall, 151 fetuses survived after birth, there were two terminations of pregnancy and one stillbirth. Among newborns, only three fetuses had symptoms of compression, all belonged to the non-isolated group (right ductus arch with ARSA, tracheoesophageal fistula with esophageal stenosis, intrauterine growth retardation). No genetic disorders and no postnatal compressive symptoms were detected in the isolated ARSA group.