The prevalence of asymptomatic carotid artery disease in patients with peripheral vascular disease

AIM: To determine the prevalence and severity of asymptomatic carotid arter y disease in patients with peripheral arterial disease using colour duplex ultrasound, and to determine any relationship to the severity of peripheral arterial disease or other associated atherosclerotic risk factors. METHOD: Two hundred patients with known peripheral arterial disease but no previous cerebrovascular history were prospectively screened for carotid ar tery disease, and any identified internal carotid artery (ICA) stenosis gra ded using established duplex ultrasound criteria. A detailed medical questi onnaire established the presence or absence of associated risk factors, and the severity of peripheral arterial disease was graded and correlated with these. RESULTS: A total of 50 patients (25%) were found to have an ICA stenosis of >50%, with 27 (13.5%) of these having >70% stenosis, Bilateral ICA stenosi s (>50%) was seen in 21 (10.5%) patients, of which 10 (5%) had bilateral st enoses of >70%. No correlation was found between the severity of peripheral arterial disease and the presence of significant carotid artery disease, o r between the latter and individual atherosclerotic risk factors. CONCLUSION: This study demonstrates a relatively high prevalence of signifi cant carotid artery disease in patients with peripheral arterial disease co mpared to the general population. The significance of this with respect to the future screening of defined populations for asymptomatic carotid artery disease is discussed, with reference to recent studies comparing surgical and medical management of asymptomatic carotid artery disease. (C) 2000 The Royal College of Radiologists.