A case of N-type right-sided aortic arch with Kommerell's diverticulum and double left brachiocephalic vein.

N-type right-sided aortic arch is a subtype of the Adachi-Williams-Nakagawa`s classification for variations in branching patterns of the aortic arch. Kommerell's diverticulum is a rare anomaly and characterized by the aneurysmal dilatation of the proximal portion of an anomalous subclavian artery or of the aorta at the origin of such subclavian artery. Kommerell's diverticulum occurs in association with a right-sided aortic arch with aberrant left subclavian artery. In the present study, we report a cadaver case of N-type right-sided aortic arch accompanied by Kommerell's diverticulum in retroesophageal origin of the left subclavian artery. Interestingly, in this case, the double left brachiocephalic vein was identified around the ascending aorta. To our knowledge, there have been no reported cases of the coexistence of right-sided aortic arch, Kommerell's diverticulum, and double left brachiocephalic vein. The right-sided aortic arch is often associated with congenital heart diseases and other cardiovascular abnormalities. Therefore, the present right-sided aortic arch with Kommerell's diverticulum and double left brachiocephalic vein may give us an important knowledge for cardiovascular anomalies in men from both clinical and embryological aspects.