Locations of TAAs include Ascending thoracic aorta (between the aortic root and brachiocephalic, or innominate, artery): 40% Aortic arch (including the brachiocephalic, carotid, and subclavian arteries): 10% Descending thoracic aorta (distal to the left subclavian artery): 35% Upper abdomen—thoracoabdominal aneurysms (TAAAs): 15% Complications Complications of TAAs include Aortic dissection Compression or erosion into adjacent structures Leak or rupture Thromboembolism Aneurysms of the ascending aorta sometimes affect the aortic root, causing aortic valve regurgitation or occlusion of the coronary arterial ostia, causing angina, myocardial infarction, or syncope.