WHO NEEDS SURVEILLANCE OF THE CONTRALATERAL CAROTID-ARTERY

BACKGROUND: Although the value of carotid endarterectomy has been prov en, postoperative surveillance remains controversial. The purpose of t his study was to determine the natural history of disease progression in the contralateral carotid artery by duplex surveillance, and to ass ess the cost of stroke prevention on this contralateral side. METHODS: Vascular laboratory records were reviewed to identify carotid endarte rectomy patients who had two or more duplex studies between 1984 and 1 995. Critical stenosis was defined as greater than or equal to 75% are a reduction. RESULTS: In all, 324 patients were followed up with duple x scans for 1 month to 11 years (mean 30.3 months). The only factors t hat correlated with progression to critical stenosis were age and init ial stenosis. Overall, 19.5% of patients progressed to critical stenos is within 5 years while the high-risk groups with age >65 years or ini tial stenosis greater than or equal to 50% progressed to critical dise ase in 27% and 39%, respectively (P less than or equal to 0.05). The c ost per stroke prevented ranged from $143,500 to $418,200 when stratif ied by initial stenosis. CONCLUSION: Patients who have undergone a car otid endarterectomy demonstrate a propensity for progression of caroti d stenosis in the unoperated (contralateral) artery, The cost/benefit ratio may be improved by varying the intensity of duplex surveillance of the contralateral carotid based on the patient's age and initial de gree of stenosis.