AORTIC ATHEROSCLEROSIS AS A SOURCE OF ARTERIAL EMBOLISM

Aortic atherosclerosis has early been recognized as a potential source of embolism. The histological finding of cholesterol clefts in small end-arteries characterized the entity of cholesterol embolism. The cli nical picture was extremely variable and the diagnosis was frequently established post-mortem or by means of invasive although insensitive p rocedures including biopsy and angiography. Therefore, cholesterol emb olism was thought to be rare. With the routine use of transesophageal echocardiography for the diagnostic workup of arterial embolism, aorti c atherosclerosis was shown to be the source of otherwise unexplainabl e embolism. Cross-sectional studies demonstrated an independent associ ation between prominent plaques of more than 4 to 5 mm of thickness or plaques with mobile components in the aortic arch. In follow-up studi es, the risk of embolic events in patients with this kind of lesions e xceeded 10 % per patient-year The results of pathological studies were consistent with these findings showing that ulcerated complex plaques carry an independent risk for embolic events. Apart from spontaneous embolism, atherosclerosis of the proximal aorta was shown to be a caus e of embolic complications during cardiac surgery and catheterization procedures which involve the aorta. Medical treatment for the preventi on of embolism in atherosclerotic disease of the aorta has not been st udied systematically. In a variant form of aortic atherosclerosis cons isting of mobile pedunculated thrombi inserting on relatively small pl aques, anticoagulant therapy has proved to be useful in small numbers of patients. Recurrent embolic events could be prevented and regressio n of the thrombotic masses has been observed.