Rare case of a five-branched aortic arch exhibiting a retroesophageal right subclavian artery and an accessory left vertebral artery

Head and neck vascular variations are common in humans, but often go undetected. They are generally asymptomatic. Awareness of such anatomical variations is clinically important for surgeons and interventional radiologists as they may pose risk for iatrogenic complications or even the potential for unanticipated fatalities.

Although aortic arch variations are relatively common, branch variations are observed and/or described variably and fairly infrequently during human cadaveric dissection.

When aberrant subclavian arteries are described in adults, they frequently involve the right side, and are usually retroesophageal with an absent right brachiocephalic trunk. The following four branches of the aortic arch found most commonly then are: a retroesophageal right subclavian artery, left subclavian artery, and right and left common carotid arteries. During cadaveric dissection of a 76-year-old White male, we observed an additional fifth branch: an accessory left vertebral artery. A combination of five such aortic arch vessels may be rare.