Anatomical variations in the branches of the aortic arch in Japanese patients.

In aortic arch surgery, preoperative evaluation of variations in the aortic arch branching is necessary. The present study investigated variations in the aortic arch branches in Japanese patients using contrast-enhanced computed tomography. In this study, we included 2,923 Japanese patients who underwent computed tomography at our institution in 2022. The following eight types of variations in the aortic arch branching were observed. Type 1, with the brachiocephalic trunk, left common carotid artery, and left subclavian artery, was found in 2,541 patients (86.9%). Additionally, seven subtypes were found in 382 patients (13.1%) as follows: Type 2, the common trunk of brachiocephalic trunk and left common carotid artery (8.0%); Type 3, with the left vertebral artery, branching directly from the aortic arch between left common carotid artery and left subclavian artery (4.3%); Type 4, left vertebral artery branching directly from the aortic arch distal to left subclavian artery (0.1%); Type 5, aberrant right subclavian artery (0.5%); Type 6, the common trunk of bilateral common carotid arteries (0.1%); Type 7, the common trunk of left common carotid artery and left subclavian artery (0.01%); and Type 8, the right aortic arch complicated with aberrant left subclavian artery (0.1%). The subtypes of the variations in aortic arch branching were found in 13.1% of Japanese patients. In this study, only a few patients had aortic disease. Further studies are required to investigate the relationships between variations in the aortic arch branching and aortic disease.