Improved methods are required to identify patients with asymptomatic carotid stenosis at high risk for stroke. The Asymptomatic Carotid Emboli Study recently showed embolic signals (ES) detected by transcranial Doppler on 2 recordings that lasted 1-hour independently predict 2-year stroke risk. ES detection is time-consuming, and whether similar predictive information could be obtained from simpler recording protocols is unknown.
Better methods of identifying which patients with asymptomatic carotid stenosis will develop stroke, are required to improve the risk-benefit ratio of carotid endarterectomy. A promising method is the detection of asymptomatic embolic signals using transcranial Doppler. Embolic signals predict stroke risk in symptomatic carotid stenosis, but their predictive role in asymptomatic carotid stenosis is uncertain.