Abstract WP177: Frequency of Carotid Plaque With High-Risk Features in Cryptogenic Stroke: Systematic Review and Meta-Analysis

Abstract

Background and Purpose: An ipsilateral non-obstructive carotid atherosclerosis (NOCA), defined as carotid plaque with <50% stenosis, is identified in 25% of cryptogenic strokes and could represent an unrecognized source of athero-embolism. We aimed to summarize available data regarding the frequency of NOCA with high-risk features in patients with cryptogenic stroke. Methods: A search of Pubmed and Ovid-Embase identified observational studies reporting carotid plaque imaging features in patients with cryptogenic stroke, from inception to July 15, 2019. The prevalence of NOCA with high-risk features in ipsilateral and contralateral carotid was determined by pooling study-specific estimates using a random-effect meta-analysis. Results: Six prospective studies enrolling a total of 255 participants with unilateral ischemic stroke in the anterior circulation were included. Carotid arteries were imaged with ultrasound, computed tomography or MRI to identify echolucency, ulceration, intraplaque hemorrhage, thrombus, or thickness ≥ 3 mm. The pooled prevalence of NOCA with high-risk features in the ipsilateral carotid was 34.0% (95% CI: 25.7 – 42.9) compared to 7.3 % (95% CI: 0.8 – 18.1) in the contralateral carotid. The odds ratio of finding a plaque with high-risk features in the ipsilateral versus the contralateral carotid was 4.1 (95% CI: 2.0 – 8.7). Conclusion: Plaques with high-risk features are four times more prevalent in the ipsilateral compared to the contralateral carotid artery in patients with cryptogenic stroke, suggesting a relationship to stroke risk. These features may aid in etiologic classification of stroke and risk stratification for secondary prevention therapy.