A three branches aortic arch variant with a bi-carotid trunk and a retro-esophageal right subclavian artery

We report observations from a female cadaver presenting a rare variation of the branches of a left-sided aortic arch. Three branches originated from the convexity of the arch in the following order: A bi-carotid trunk giving origin to the right and left common carotid arteries, a left subclavian artery and a right subclavian artery. The anomalous right subclavian artery ran obliquely from the left to the right, between the oesophagus and the vertebral column to reach the right upper limb.