Fig. 1

Representative images showing different degrees of AAC. Maximal intensity projection image was used to assess AAC. (A, C, E, G) Optimized images for aortic arch visualization. These images were used to assess the calcification involving the ratio of the aortic arch length. (B, D, F, H) Images that visually overlapped the vascular lumen of the aortic arch were assessed to identify the calcification involving the ratio of the vessel circumference; (A, B) no AAC; (C, D) mild AAC: calcification involving ≤ 1/3rd of aortic arch length or circumference; (E, F) moderate AAC: calcification involving > 1/3rd of aortic arch length and circumference, but not both > 2/3rd of aortic arch length and circumference; (G, H) severe AAC: calcification involving > 2/3rd of aortic arch length and circumference. Notably, the calcification in the innominate, left common carotid, and left subclavian arteries was not included as AAC. AAC = aortic arch calcification.