Asymptomatic carotid stenosis in patients on medical treatment alone.

OBJECTIVE: the aim of this study was to investigate the effect of currently recommended medical treatment (MT) on changes in carotid stenosis in a group of asymptomatic patients taken from the Asymptomatic Carotid Surgery Trial (ACST). METHOD: collaborators in ACST were given information on MT for stroke prevention (including antiplatelet agents, lipid-lowering drugs, diabetic and hypertension control). Patients underwent clinical examination and duplex scanning at entry, 4 months following randomisation and annually thereafter. The cohort of patients studied were those randomised to MT with complete follow up duplex datasets at four years (n=219). None had undergone carotid endarterectomy (CEA) or developed ipsilateral carotid symptoms. RESULTS: there was no change in median carotid stenosis over four years (baseline 79% (IQR 10%) and 4 year median 79% (IQR 10%)) a median difference of 0 with Q1=-5 and Q3=+5 (p=0.98 Wilcoxon one sample test), whilst in many patients' stenoses progressed and regressed during this time. No individual MT variable correlated with stenosis progression or regression. CONCLUSION: in this group of ACST patients on MT, mean carotid stenosis was unchanged over 4 years. Individual patients' stenoses progressed (and regressed) without symptoms occurring. An increase in stenosis should not be the sole basis for deciding to operate on an asymptomatic patient.