Two Common Trunks Arising From Arch of Aorta: Case Report and Literature Review of A Very Rare Variation.

Arch of aorta normally gives off three branches, the brachiocephalic trunk, left common carotid artery and left subclavian artery. Due to its complex development, variations in the branching pattern are not infrequent and since many such variants remain asymptomatic, they are detected incidentally at diagnostic imaging, autopsy and surgery. The classical branching pattern is reported to be present in 63.5%-89.4% cases and the most common variant observed is the presence of common trunk of brachiocephalic and left common carotid arteries. Direct aortic arch origin of left vertebral artery is the second most common pattern observed. We report here an extremely rare branching pattern of two common trunks arising from the arch, the first common trunk of brachiocephalic and left common carotid arteries and the second designated as vertebro-subclavian trunk, the common trunk of origin of left subclavian and left vertebral arteries. To the best of our knowledge this is the second such case to be reported.