Anomalies of the aortic arch are rare, with a right arch occurring in about 1 of every 1000 individuals. Unlike the right aortic arch co-existing with an aberrant left subclavian artery, the variant with mirror-imaged branching is often associated with congenital cardiac malformations, most commonly tetralogy of Fallot with pulmonary stenosis or pulmonary atresia, and common arterial trunk. A right arch associated with bilateral arterial ducts and non-confluent pulmonary arteries is extremely uncommon. We could find but a single report of this combination, that patient having no associated intra-cardiac defects.¹

Our patient was delivered uneventfully at term after an uncomplicated pregnancy. She was evaluated at 24 hours of life for asymptomatic cyanosis. An echocardiogram (Figs. 1 and 2) and a computed-tomography angiogram (Fig. 3) revealed the following:

Figure 1. Sub-costal coronal view demonstrating the left-sided right atrium (RA), the discordant atrioventricular connection, the large ventricular septal defect (VSD) and the right-sided aorta (Ao). Right and left ventricles (RC and LV).

Figure 2. Supra-sternal modified short axis view demonstrating the non-confluent branch right and left pulmonary arteries (RPA and LPA), with the LPA connected via a left-sided patent arterial duct (L-PAD).

Figure 3. CT angiogram 3-D re-construction of the right aortic arch (RAA) with mirror-imaged branching, and non-confluent branch pulmonary arteries, with the right pulmonary artery (RPA) off the descending aorta via a right-sided patent arterial duct (R-PAD), and the left pulmonary artery (LPA) off the left brachiocephalic artery (L-BCA) via a left-sided patent arterial duct (L-PAD).

• A midline heart with mirror-imaged atrial arrangement, discordant atrioventricular connections, pulmonary atresia, and the aorta arising exclusively from the morphologically right ventricle (Fig. 1),
• Large atrial and ventricular septal defects (VSD),
• A right-sided aortic (Ao) arch (RAA) with mirror-imaged branching,
• Pulmonary atresia with non-confluent pulmonary arteries (Fig. 2),
• The right pulmonary artery (RPA) arose from the descending aorta (Desc Ao) via a right-sided patent arterial duct (R-PAD) (Fig. 3),
• The left pulmonary artery (LPA) arose from the left brachiocephalic artery (L-BCA) via a left-sided patent arterial duct (L-PAD) (Fig. 3).

Initial management was infusion of prostaglandin, followed at 9 days of age by surgical unifocalization of the right and left pulmonary arteries and creation of a central Gore-Tex aorto-pulmonary shunt of 3 millimetres diameter, the patient weighing 2.6 kilograms. Due to cyanosis, and stenosis of the newly created confluence of the pulmonary arteries, the confluence was augmented by a patch, and the shunt replaced by a Gore-Tex tube of 3.5 millimetres diameter, this procedure being performed at 76 days of age. Subsequently, at 7 months of age, we created a left sided bidirectional cavopulmonary anastomosis, performed a left pulmonary arterioplasty, and divided the central shunt. Our eventual plan is for complete biventricular repair if the anatomy proves to be favourable upon repeat imaging in the future. Otherwise, she will undergo completion of her Fontan circulation.