Right-Sided Double Aortic Arch in Tetralogy of Fallot

A 9-month-old infant with tetralogy of Fallot underwent preoperative cardiac catheterization, because echocardiographic results led us to suspect a right aortic arch with an anomalous configuration of the aortic arch branches. A mild inspiratory stridor could be heard when the baby cried. At cardiac catheterization, the diagnosis of tetralogy of Fallot was confirmed (Fig. 1), and the right-sided course of the angiographic catheter initially seemed to confirm the diagnosis of right aortic arch. However, the aortic angiogram revealed a double aortic arch with a left component that was slightly smaller and lower than the right one. The left common carotid artery and the left subclavian artery arose individually from the left component of the aortic arch, and the right common carotid artery and the right subclavian artery arose individually from the right aortic arch (Fig. 2). Both aortic arches mildly compressed the lateral aspects of the trachea and overrode the right and left bronchi, before joining on the right side of the posterior mediastinum and continuing as a right-sided descending aorta. No pressure gradient between the ascending and descending aorta was recorded. Surgical treatment, consisting of ventricular septal defect closure, right ventricular outflow tract enlargement, and resection of that portion of the left aortic arch between its peripheral branches, successfully relieved the mild upper-airway obstruction.

Fig. 1 Left ventriculography in the right anterior oblique view (A) and left anterior oblique view (B) shows the aortic arch anomaly and the aorta overriding the ventricular spetal defect (arrow).

Ao = aorta; LV = left ventricle; PA = pulmonary artery; RV = right ventricle

Fig. 2 Postero-anterior view (A) and lateral view (B) of the aortic arch confirm the diagnosis of double aortic arch with right-sided descending aorta. The right common carotid artery and the right subclavian artery arise individually from the right component of the double aortic arch. Similarly, the slightly smaller and lower-sided left component of the aortic arch give rise to the left common carotid artery and the left subclavian artery.

LCA = left carotid artery; LSA = left subclavian artery;

RCA = right carotid artery; RSA = right subclavian artery