Symptomatic and asymptomatic carotid artery lesions in peripheral vascular disease: a prospective study

To assess the incidence and severity of internal carotid artery lesions in patients who were referred to a single institution with peripheral obliterative atherosclerotic disease (POAD) as their chief complaint, in order to identify symptomatic and asymptomatic subjects at risk of stroke who would benefit from surgery.

Consecutive patients with clinically and Doppler scan-proven POAD underwent prospective screening for the presence of carotid symptomatic and asymptomatic atherosclerotic lesions with duplex ultrasound scan (DUS). Associated risk factors for atherosclerosis, i.e. age, sex, diabetes, hypertension, hyperlipidemia, history of smoking and history of coronary artery disease were assessed and recorded. Univariate analysis was performed to correlate the risk factors with the presence of POAD and carotid lesions.

Three-hundred and twelve consecutive patients were evaluated over an 18-month period. A 30% or greater carotid stenosis was detected by DUS in 189 patients (19 bilateral); 57 (30%) of these had neurologic symptoms, 19 of whom had a 70-99% carotid lesion, whereas 65 of the 132 asymptomatic patients had 60-99% carotid stenosis. Univariate analysis revealed no differences in the symptomatic and asymptomatic groups between patients who were potential candidates for carotid endarterectomy according to the North American Symptomatic Carotid Endarterectomy Trial and the Asymptomatic Carotid Atherosclerotic Study Group guidelines, respectively, and those who were not as regards associated atherosclerotic risk factors and severity of POAD. All but 2 (n = 17) symptomatic and 18 asymptomatic patients underwent carotid endarterectomy based on DUS criteria alone. The perioperative stroke risk and mortality rates were 0%.

Routine carotid DUS screening of 312 consecutive patients with POAD revealed that 19 patients with symptoms and 65 (5 bilateral) without symptoms would benefit from surgery, representing 27% of the series considered.