Prognostic Effects of Platelet Reactivity in Patients with Carotid Artery Stenting or Carotid Artery Endarterectomy: A Systematic Review and Meta-Analysis.

Introduction: High On-Treatment Platelet Reactivity (HTPR) is frequently observed after carotid endarterectomy (CEA) or stenting (CAS), but its association with adverse events remains uncertain. This systematic review and meta-analysis evaluate the association between HTPR and recurrent vascular events in these patients.

Methods: EMBASE, PubMed, and Cochrane Library were searched for eligible studies from inception to July 1, 2024. Two independent reviewers screened the records, extracted data, and assessed the bias using predefined criteria. A meta-analysis was conducted using RevMan 5.4 software. The primary outcome was the risk of recurrent ischemic events in patients with HTPR. Secondary outcomes included the risk of hemorrhage and carotid restenosis.

Results: Eight studies involving 1,052 patients were included in the meta-analysis. This metaanalysis found that HTPR significantly increased the risk of adverse vascular events (OR = 2.41, 95% CI: 1.37-4.24), particularly in CAS patients (OR = 1.85, 95% CI: 1.14-2.98), but not in CEA patients (OR = 4.53, 95% CI: 0.52-39.12). Furthermore, HTPR was not significantly associated with an increased risk of bleeding (OR = 0.90, 95% CI: 0.24-3.37) or carotid restenosis (OR = 1.70, 95% CI: 0.38-7.55).

Discussion: This meta-analysis demonstrates that HTPR may increase the risk of recurrent ischemic events in CAS patients, supporting the clinical utility of platelet function monitoring in this population. However, no significant association was observed between HTPR and hemorrhage or restenosis. These findings should be interpreted cautiously due to study limitations, including small sample sizes and heterogeneity in platelet function assessment methodologies. Large-scale prospective studies with standardized protocols are warranted to validate these observations.

Conclusion: HTPR may be associated with an increased risk of recurrent ischemic events in patients undergoing CAS, highlighting the potential value of platelet function monitoring.