A double aortic arch mimicking a right aortic arch with an aberrant subclavian artery.

A 4-month-old boy was referred for persistent respiratory symptoms despite having undergone division of the ligamentum arteriosus for the diagnosis of a right aortic arch with an aberrant left subclavian artery. A computed tomography scan demonstrated symmetric arch vessels around the trachea at the thoracic inlet, with the left common carotid artery being tethered posteriorly, more suggestive of a double aortic arch with an atretic left arch between the left common carotid and subclavian arteries. This diagnosis was confirmed intraoperatively, and division of the atretic portion released the bronchial obstruction. This case highlights the importance of careful evaluation of the vascular anatomy.