Purpose: To examine an unselective population of fetuses with right aortic arch (RAA) and suggest perinatal management. Second, to evaluate the importance and possible implication of fetal MRI in those cases.
Methods: Retrospective study of 36 patients with RAA diagnosed prenatally between 2006 and 2017 in a tertiary referral center.
Results: 32 fetuses were diagnosed with RAA and 4 with double aortic arch (DAA). 7 (19, 5%) cases had intracardiac abnormalities. Tetralogy of the Fallot was the most frequent one. Other extracardiac malformations were observed in 11/36 (30, 6%). Karyotype was available in 16 (44, 5%) cases. Two had 22q11.2 microdeletion, two trisomy 21, and one 20p12.2 duplication. Two needed surgery for respiratory symptoms. A newborn was identified with epilepsy, Lennox-Gastaud syndrome and Pallister-Killian syndrome postnatally and another one with showed hyperreflexia and premature closer of the fontanelle. Three feticides were performed for pregnancy termination in one case with 22q11 deletion, trisomy 21, and partial agenesis of corpus callosum.
Conclusion: RAA can be detected by fetal echocardiography and it is associated with other cardiac or non-cardiac abnormalities, 22q11 microdeletion, trisomy 21, and other chromosomal abnormalities. karyotyping should be offered in any case of RAA, irrespective of co-existing malformations. Fetal MRI is a promising diagnostic tool for assessment of congenital cardiovascular abnormalities and extracardiac anomalies.
Keywords: 22q11.2 microdeletion; Fetal MRI; Prenatal; Right aortic arch.