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Right cervical aortic arch with unusual origin of left carotid artery.

A 9-year-old boy presented with a history of lower respiratory infections and stridor. At age 18 months, he had undergone surgery for inguinal hernia and tracheoesophageal fistula. Physical examination now revealed a pulsatile mass in the right supraclavicular region. 
 
Transthoracic echocardiography and aortography showed a right cervical aortic arch: the right subclavian artery and right carotid artery arose from the right cervical arch (Fig. 1), and the left carotid artery originated from the ascending aorta (Fig. 2). Computed tomography revealed this anatomic configuration and tracheal compression (Figs. 3 and ​and4).4). The patient was referred for cardiac surgery. 
 
 
 
Fig. 4 Three-dimensional, volume-rendered, coronal 64-slice multidetector computed tomographic image shows tracheal compression, a right aortic arch, and a left carotid artery that arises from the ascending aorta. 
 
 
 
 
 
Fig. 3 Axial 64-slice multidetector computed tomographic image shows a right aortic arch and tracheal compression. 
 
 
 
 
 
Fig. 2 Aortography during cardiac catheterization shows a right aortic arch and a left carotid artery that arises from the ascending aorta. 
 
 
 
 
 
Fig. 1 Aortography during cardiac catheterization shows a right aortic arch.