The Role of Extracellular Vesicles in Transient Ischaemic Attacks and Ischaemic Stroke: A Systematic Review

Stroke is the second leading cause of death and a major contributor of long‐term disability globally. Ischaemic stroke (IS) is the most common type of stroke; characterised by a blood clot that causes oxygen deprivation in the brain. Survivors often face long‐lasting disabilities, imposing significant social and economic burden. Up to a quarter of IS are preceded by a transient ischaemic attack (TIA), where temporary symptoms occur due to a short‐term interruption in blood flow. Currently, there is no reliable method to identify which TIA patients are at greatest risk of stroke. Early identification of circulating biomarkers in this cohort could inform clinical follow‐up and help prevent future strokes. Extracellular vesicles (EVs) are membrane bound nanoparticles, released by all cell types playing key roles in cell‐to‐cell communication. EVs have recently emerged as effective biomarkers in disease diagnostics, yet their involvement in IS and TIA remains poorly understood. To explore this, a systematic review was undertaken following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) Guidelines. A comprehensive search of PubMed, Scopus and Web of Science up to May 2025 yielded 1206 articles, of which 31 met the inclusion criteria and were analysed. This review highlights the necessity for standardised methodologies, particularly in EV isolation and characterisation, to allow data comparability and clarity of the role of EVs in the pathophysiology of IS and TIA.