Background and purpose: Many reports have shown an association between hypoechoic (echolucent) carotid atherosclerotic plaques and unstable features. In this meta-analysis our aim was to determine the role of carotid plaque echogenicity in predicting future cerebrovascular (CV) symptoms.

Methods: Electronic databases (PubMed, MEDLINE, EMBASE and Cochrane Center Register) up to September 2015 were systematically searched. Studies with ultrasound-based characterization of carotid artery plaque echogenicity and its association with focal neurological symptoms of vascular origin were eligible for analysis. In the meta-analysis, heterogeneity was measured usingI2 statistics and publication bias was evaluated using the Begg–Mazumdar test. In addition several comparisons between subgroups were performed.

Results: Of 1387 identified reports, eight studies with asymptomatic patients and three studies with symptomatic patients were meta-analyzed. Pooled analysis showed an association between echolucent carotid plaques and future CV events in asymptomatic patients [relative risk 2.72 (95% confidence interval 1.86–3.96)] and recurrent symptoms in symptomatic patients [relative risk 2.97 (95% confidence interval 1.85–4.78)]. The association was preserved for all stenosis degrees in asymptomatic patients, whilst patients with echolucent plaques and severe stenosis were at higher risk of future events. Also, computer-assisted methods for assessment of carotid plaque echogenicity and studies analyzing ultrasound data collected after the year 2000 showed better prediction.

Conclusions: In asymptomatic and symptomatic patients, analysis of carotid plaque echogenicity could identify those at high risk of CV events.