Embolic Signals And Prediction of Ipsilateral Stroke or Transient Ischemic Attack in Asymptomatic Carotid Stenosis

Background and Purpose— We tested the hypothesis that transcranial Dopplerembolic signal (ES) detection identifies an increased risk of ipsilateral carotid stroke or transient ischemic attack (TIA) in subjects with asymptomatic severe carotid stenosis. Methods— Subjects with duplex-determined 60% to 99% carotid stenosis, without other apparent cerebroembolic sources, underwent 6-monthly neurological assessment and 60-minute ES monitoring. ES positivity was defined as ≥1 ES detected in ≥1 study, ES negativity as no ES in any study, and consistent ES negativity as no ES in any study where ≥6 studies were performed. Ratesof ipsilateral carotid stroke/TIA were calculated using Kaplan–Meier analysis and correlated with ES status using odds ratios (ORs) and Cox proportional hazards regression analysis. Results— A total of 202 subjects (138 male; mean age 74 years; mean follow-up 34 months) were recruited. The average annual rate of ipsilateral carotid stroke/TIA was 3.1%. A total of 231 arteries were monitore...