Elevated mean platelet volume is associated with poor outcome after mechanical thrombectomy

Background Elevated mean platelet volume (MPV), indicating higher platelet activity, could be a predictor of prognosis in patients with acute ischemic stroke receiving medical therapy. Objective To investigate the relationship between MPV and functional outcome in patients with acute anterior circulation stroke 3 months after undergoing mechanical thrombectomy (MT). Methods A total of 153 consecutive patients with acute stroke following MT, in two separate stroke centers, were enrolled between May 2013 and March 2016. MPV was measured on admission. Subjects were divided into two groups according to average MPV level. Univariate and multivariate analyses were performed. MPV was also incorporated into the Houston IA Therapy (HIAT) score, which was developed as a scoring system to predict poor prognosis, and the prediction capability was compared with the HIAT score alone. Results The average MPV was 10.4 fL. Patients with high MPV had a significantly lower rate of functional independence (28.9% vs 57.1%, p=0.000). After multivariable analysis, elevated MPV remained an independent predictor of unfavorable outcome (OR=3.93, 95% CI 1.73 to 8.94, p=0.001). When the MPV cut-off value was set at 10.4 fL using the receiver operating characteristic (ROC) analysis, MPV ≥10.4 fL predicted unfavorable outcome with 62.1% sensitivity and 66.7% specificity, respectively. Addition of MPV to the HIAT score did not improve predictive power compared with the HIAT score system alone by a comparison of the areas under the two ROC curves (0.70 vs 0.62, p=0.174). Conclusions Elevated MPV is an independent predictor of poor outcome in patients with acute anterior circulation stroke undergoing MT at 3 months.