Aberrant Right Subclavian Artery in Prenatal Diagnosis: A Retrospective Study

Aim: Aberrant right subclavian artery (ARSA) is the most common anomaly of the aortic arch and occurs in 1-2% of the population. Although it is usually asymptomatic, its prenatal detection has gained importance due to associations with chromosomal abnormalities, including trisomy 21 and 22q11.2 microdeletion. This study examines isolated (iARSA) and non-isolated ARSA (niARSA), focusing on diagnostic approaches and neonatal outcomes. Material and Method: In this retrospective study, 29 pregnancies diagnosed with ARSA between October 2022 and January 2024 were analyzed. Fetuses were classified as iARSA or niARSA based on additional structural or chromosomal findings. Data were collected from high-resolution ultrasound examinations and medical records, and statistical comparisons were performed using SPSS v25.0. Results: There were a total of 29 cases of ARSA, of which 16 were iARSA (55.2%) and 13 were niARSA (44.8%). Non-invasive prenatal testing was performed in 68.7% of iARSA cases, all of which had normal results. In contrast, invasive testing was performed in 38.5% of niARSA cases, with chromosomal abnormalities detected in two cases (trisomy 21). Neonatal outcomes were favorable in iARSA, with 15 cases discharged without complications. NiARSA cases had higher morbidity, including NICU admissions (46%) and congenital heart defects, which in some cases required surgical intervention. Conclusion: ARSA is an important marker in prenatal diagnosis. While iARSA generally indicates favorable outcomes, niARSA correlates strongly with unfavorable neonatal outcomes and chromosomal abnormalities. The distinction between iARSA and niARSA is crucial for tailored prenatal management and optimization of neonatal care strategies.