The Rare Association of Truncus Arteriosus with a Cervical Double Aortic Arch Presenting with Left Main Bronchial Compression

Abstract

Truncus arteriosus, a double aortic arch, and a cervical aortic arch are all rare cardiovascular anomalies. We experienced a unique female newborn with the rare combination of truncus arteriosus with a cervical double aortic arch, which probably resulted from abnormal persistence of the bilateral 2nd or 3rd rather than the 4thembryonic aortic arches and failure of regression of the right 8th somitic segment of the right dorsal aorta. She presented with respiratory distress soon after birth, which was initially attributed to the vascular ring and hypertensive pulmonary arteries. Our inability to relieve her respiratory compromise by surgical division of the vascular ring and main pulmonary artery banding prompted the diagnosis of left main bronchial compression caused by a posteriorly displaced dilated ascending aorta that compressed the right pulmonary artery and left main bronchus against the descending aorta. The patient then underwent successful left main bronchus stent implantation. We speculate the cervical double aortic arch is redundant in nature and is a loose ring that may not cause tracheal compression. Nevertheless, a posteriorly displaced dilated ascending aorta in patients with truncus arteriosus may compress the right pulmonary artery and the main bronchus on the side of the aortic arch against the descending aorta.