Diagnosis of isolated right aortic arch: Accuracy of prenatal diagnosis, associated genomic disorders and interest of systematic postnatal imaging. The ARCADE multicentre retrospective observational study

Abstract

Prenatal diagnosis of isolated right aortic arch (RAA) have increased during the past decades. However, diagnosis accuracy, genetic testing, and post-natal follow-up are still not consensual. We aimed to analyse French pediatric cardiologists practice regarding prenatal diagnosis of isolated RAA. We collected all livebirth with isolated RAA prenatally diagnosed in 14 French congenital heart disease centres from 2015 to 2020. We compare, using kappa coefficient of concordance, the anatomical position of aortic arch, ductus arteriosus and aberrant left subclavian artery described by prenatal echo, postnatal echo, and CT scan when available. We also assessed available genetic results and functional postnatal status. We included 309 neonates with prenatal diagnosis of isolated RAA. Regarding patients with an isolated RAA, left ductus arteriosus have been described in 76% of cases. Diagnosis of aberrant left subclavian artery was missing in 73% of cases. Four patients with prenatal isolated RAA had a postnatal diagnosis of double aortic arch (DAA). Correlation between pre- and post-natal echo was excellent regarding aortic arch position (kappa = 0.97). 108 neonates (35%) underwent postnatal CT scan due to onset of respiratory symptoms (53%) or systematic centre protocol (47%). CT-scan revealed five more unknown DAA. Correlation between prenatal echo and CT-scan was good (kappa = 0.79). Furthermore, systematic CT-scan showed 13 major tracheal compression resulting in six arterial ring surgeries during the study period. Lastly, 165 patients (53%) underwent a genetic testing. Nine patients (5.4%) presented a 22q11 deletion. Performance of prenatal diagnosis of isolated RAA is excellent, with a good correlation between pre- and post-natal echocardiography or gold standard-CT scan. Prenatal diagnosis of aberrant left subclavian artery and DAA is still challenging. CT scan improve anatomical description and functional impact of aortic arch anomalies and may be proposed to complete postnatal follow-up. Lastly, amniocentesis should be considered to detect genetic disorders.