Separate origin of left external and internal carotid arteries directly from aortic arch in a patient with double outlet right ventricle.

We report a case of a 1-year-old boy with double outlet right ventricle where computed tomography (CT) angiography incidentally demonstrated the separate origin of the left external and internal carotid arteries directly from the left-sided aortic arch with absence of a left common carotid artery. The case highlights the underlying embryological hypothesis as well as the importance of CT angiography in identifying anomalies of the aortic arch and arch vessels in the setting of complex congenital heart defects.