Embolic Signals And Prediction of Ipsilateral Stroke or Transient Ischemic Attack in Asymptomatic Carotid Stenosis
- 1 June 2005
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Stroke
- Vol. 36 (6), 1128-1133
- https://doi.org/10.1161/01.str.0000166059.30464.0a
Abstract
Background and Purpose— We tested the hypothesis that transcranial Doppler embolic 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. Rates of 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 monitored at least once (mean 4.3 studies/artery). Six of 60 (10.0%) ES-positive arteries had an ipsilateral carotid stroke/TIA compared with 12 of 171 (7.0%) ES-negative arteries (OR, 1.47; 95% CI, 0.43, 4.48; P =0.624) and 2 of 41 (4.9%) consistently ES-negative arteries (OR, 2.17; 95% CI, 0.36, 22.90; P =0.59). Differences in survival free of ipsilateral carotid stroke/TIA according to ES status were not statistically significant. Conclusions— Although there were more ipsilateral carotid cerebrovascular events among ES-positive arteries, this was not statistically significant. Less labor-intensive techniques are required to make further study and clinical application practical.Keywords
This publication has 15 references indexed in Scilit:
- Re: Interhemispheric Asymmetries of Motor Cortex Excitability in the Postacute Stroke StageStroke, 2004
- The Causes and Risk of Stroke in Patients with Asymptomatic Internal-Carotid-Artery StenosisNew England Journal of Medicine, 2000
- Asymptomatic cerebral embolic signals in symptomatic and asymptomatic carotid artery diseaseBrain, 1995
- Endarterectomy for Asymptomatic Carotid Artery StenosisJAMA, 1995
- Risk of stroke in the distribution of an asymptomatic carotid arteryThe Lancet, 1995
- Cerebral microembolism in symptomatic and asymptomatic high‐grade internal carotid artery stenosisNeurology, 1994
- Efficacy of Carotid Endarterectomy for Asymptomatic Carotid StenosisNew England Journal of Medicine, 1993
- Outcome in Patients with Asymptomatic Neck BruitsNew England Journal of Medicine, 1986
- Natural History of Asymptomatic Carotid PlaqueArchives of Surgery, 1985
- A METHOD FOR THE ANALYSIS OF SIGMOID STIMULUS‐RESPONSE CURVESImmunology & Cell Biology, 1979