Postnatal outcome of fetal aberrant right subclavian artery: a single center study

This study aims to explore the correlation between fetal aberrant right subclavian artery (ARSA) and chromosomal disorders, with a specific focus on Down syndrome and DiGeorge syndrome.

From November 2017 to February 2020, we conducted fetal anomaly screening and assessed the fetal heart in 8494 at our institution. The right subclavian artery tracing was assessed using Doppler ultrasonography following the 3-vessel and tracheal views (3VTV) in the fetal heart scan.

ARSA was found in 31 fetuses, which accounts for 0.36% of the total of 8494 fetuses. 96.8% of fetuses with ARSA were found to have normal chromosomal analysis. We identified only one case of trisomy 21 as the chromosomal condition present. In 80% of the identified ARSA, there were no additional associated findings.

ARSA is a rare condition that often does not manifest any concomitant abnormalities. The majority of ARSA instances identified in the second trimester are euploid. If ARSA is the only sonographic finding during fetal anomaly screening and there are no maternal or laboratory risk factors, further evaluation with non-invasive diagnostics may be recommended. Non-invasive genetic testing may be used for additional investigation.