Bridging Evidence Gaps in Severe Carotid Stenosis: A Systematic Review of PreRevascularization Risk Stratification,
Objective:
Severe carotid artery stenosis (CAS) impairs cerebral blood flow and cognitive function. Revascularization may improve outcomes, but patient selection and timing remain challenging. This review synthesizes evidence on pre-revascularization risk factors. This systematic review synthesises pre-revascularization evidence on CAS-related cognitive decline and evaluates timing, restenosis, high-risk subgroups (dialysis, radiation-induced, sex), bilateral stenosis, hyperperfusion, and risk for stroke/death/MI outcomes.
Method:
A systematic search of PubMed, Scopus, EBSCO, Web of Science, SciFinder, and Emerald databases identified 22 published studies that reported quantitative prerevascularization data between 2013 and 2026. The search was restricted to English-language studies.
Results:
Severe CAS (≥70%) impairs memory, attention, executive function (MMSE +0.9 post-revascularization, p=0.019; MoCA R=-0.359, p<0.001). Modern medical therapy reduced 120-day stroke risk to 1.97% (vs historical 5%); large CIL volume (≥4000 mm³) predicts stroke (OR 4.6); urgent TFCAS riskier than CEA (6.5% vs 4.0%); restenosis higher after CAS (40% vs 18% CEA). High-risk subgroups: dialysis (4.7% 30-day mortality; 43.4% 3-year survival), radiation-induced (86% vulnerable plaques), female TFCAS (OR 2.85 stroke/death), contralateral occlusion (CAS OR 2.90), octogenarians (TF-CAS 6.6% vs CEA 2.5%). Bilateral stenosis requires CVR-guided staging.
Conclusion:
Pre-revascularization cognitive assessment identifies treatment-responsive deficits. Timing should be individualized (delay large CIL); CEA preferred for high-risk anatomy. Novel risk stratification (dialysis, radiation, female sex, bilateral CVR) guides patient selection beyond traditional stenosis degree.
