Assessment of the level of circulating microvesicles in ischemic stroke

Objective. To analyze the level of circulating microvesicles (MV) in the peripheral blood of patients during the acute phase of ischemic stroke (IS) and to evaluate their relationship with clinical parameters. Material and methods. The study included 47 patients diagnosed with IS on Day 1 after disease onset, along with a control group of 50 healthy subjects. Flow cytometric analysis was performed to measure total levels of circulating MVs and the platelet-derived MVs (pMVs). Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) and the Modified Rankin Scale (mRs) at admission and at 14 and 28 days. Results. The total levels of MVs in patients with IS were significantly elevated (median 4.2×106/mL) compared to the control group (1.11×106/mL; p<0.05). A positive correlation was observed between total MV concentration and stroke severity, as measured by the NIHSS at admission (r=0.30; p=0.03), after 14 days (r=0.51; p=0.0003), and after 28 days (r=0.50; p=0.0001). Moreover, a correlation was noted with the mRs values at 14 days (r=0.40; p=0.005) and at 28 days (r=0.43; p=0.002). Among patients with atrial fibrillation (AF), the proportion of pMVs was significantly higher compared to those without AF (34% vs. 21%; p=0.007). Receiver Operating Characteristic (ROC) analysis indicated that the blood MV level demonstrates good discriminatory capability as a biomarker of ischemic stroke severity at 28 days (area under the ROC curve=0.81). Conclusions. The level of circulating MVs is substantially increased in patients during the acute phase of IS, correlating with stroke severity and functional outcomes. This biomarker may serve as a prognostic indicator for patient recovery. Furthermore, the elevated pMV proportion associated with AF may be critical for the timely diagnosis of the cardioembolic subtype of IS.