Identifying asymptomatic patients at high-risk for stroke

Area of Science:

• Neurology
• Vascular Surgery
• Cardiology

Background:

• Carotid endarterectomy and stenting significantly reduce stroke risk in asymptomatic patients with carotid artery stenosis.
• Current interventions offer moderate absolute benefits, necessitating identification of high-risk subgroups for maximized effectiveness.
• Existing guidelines for carotid intervention in asymptomatic patients with tight stenosis lack conclusive evidence for their utility.

Purpose of the Study:

• To summarize evidence on high-risk features predicting future stroke in asymptomatic patients with carotid artery stenosis.
• To review clinical, imaging, and plaque characteristics associated with increased long-term stroke risk.
• To highlight the need for further research to refine risk stratification and optimize intervention strategies.

Main Methods:

• Systematic review of existing literature on risk factors for stroke in asymptomatic carotid stenosis.
• Analysis of clinical features, imaging findings, and plaque characteristics.
• Evaluation of current European guidelines and their evidence base.

Main Results:

• Limited reliable data exists on specific high-risk features.
• Potential high-risk indicators include contralateral symptoms, silent brain infarcts, stenosis progression, impaired cerebrovascular reactivity, echolucent plaques, large plaque size (≥80 mm), intra-plaque hemorrhage, lipid-rich necrotic core, and thin/ruptured fibrous caps.
• Ongoing trials may lack power to identify high-risk subgroups with significantly higher absolute treatment gains.

Conclusions:

• Accurate identification of high-risk asymptomatic patients with carotid artery stenosis is essential for optimizing intervention benefits.
• Further large-scale contemporary cohort studies are needed to clarify the utility of various high-risk features.
• Refined risk stratification can improve the effectiveness of carotid revascularization strategies.