A right-left aortic arch pattern made up by a bicarotid trunk, a left subclavian, a left vertebral and a right retroesophageal subclavian artery.

We present several vascular variations of the aortic arch vessels observed in a 35-year-old man during magnetic resonance angiography (MRA). The arterial branches of the aortic arch are from right to left: a bicarotid trunk, a left vertebral artery, a left subclavian artery, and a right retroesophageal subclavian artery. The right vertebral artery arises from the right carotid artery. Although a right retroesophageal subclavian artery has been reported in association with different anatomic variations of the aortic arch, to our knowledge this is the first MRA description of this particular combination of variations.