Abstract
To clarify the incidence of extracranial carotid lesions in patients with aortic aneurysm and arteriosclerosis obliterans, carotid ultrasonography was performed in 41 patients with aortic aneurysm (AA group) and 62 patients with arteriosclerosis obliterans (ASO group). In this study, aortic aneurysm (AA) was diagnosed when an enlarged aorta measured more than 40mm in diameter (or infra-renal aorta more than 30mm in diameter) or when a pseudo-lumen was demonstrated within the aortic wall by computed tomography (CT) and angiography. Abdominal AA was detected in 30 patients, thoracic AA in 7, and dissecting AA in 4. ASO in patients with intermittent claudication showed obstruction of peripheral arteries on angiography. The control group consisted of 40 age-matched controls (mean age: 73.4 years) who met 4 criteria: 1) ankle pressure index more than 1.0; 2) absence of pulsating abnormal mass in the abdomen; 3) absence of dilated aorta on chest X-ray film; and 4) absence of cerebrovascular lesion on brain CT. Plaque, one of the carotid lesions seen on B-mode ultrasonography, was defined as a localized thickened intima-media complex measuring more than 2.1mm. Furthermore, plaque was divided into two types according to the ratio of plaque length to thickness; mural plaque (≥3) and nodular plaque (<3). In the AA and ASO groups, the ratio of males to females, the incidence of hypertension and smoking were significantly higher than in the control group. Compared to controls, patients with more than three of four risk factors (hypertension, diabetes, hypercholesterolemia, and smoking) were significantly more frequent. Carotid lesions were seen in 68.3% of the AA group, and in 85.5% of the ASO group. The incidence of carotid lesions was significantly higher than that in the control group, although there was also a significant difference between the AA and ASO groups. The ratio of plaque to carotid arteries was also elevated in both the AA and ASO groups. Especially, mural plaque was frequently noted in the ASO group, while the mean size of mural plaque was larger in the AA group. These findings suggest that patients with either aortic aneurysms or arteriosclerosis obliterans were more likely to have advanced carotid lesions, but the probability was significantly higher in the former. These patients, therefore, should be managed with caution to check for carotid lesions and cerebrovascular disease. If possible, the occurrance or progression of cerebrovascular disease should be prevented.
