Aortic Atherosclerosis and Embolic Events

Abstract

Aortic plaques are a manifestation of the general process of atherosclerosis in which there is a progressive accumulation of cholesterol and other lipids in the intimal-medial layer of the aorta with secondary inflammation, repetitive fibrous tissue deposition, and eventually luminal surface erosions and appearance of often mobile thrombi protruding into the lumen of the aorta. Aortic plaques may give rise to two types of emboli: thromboemboli and atheroemboli (cholesterol crystal emboli). Thromboemboli are relatively large, tend to occlude medium to large arteries, and cause strokes, transient ischemic attacks, and renal infarcts and other forms of peripheral thromboembolism. Cholesterol crystal emboli are relatively minute, tend to occlude small arteries and arterioles, and may cause the blue toe syndrome, new or worsening renal insufficiency, gut ischemia, etc. Transesophageal echocardiography remains the gold standard for visualization of aortic plaques in the thoracic aorta. There are no proven therapies for aortic embolism per se; general atherosclerosis management strategies are recommended.