Prognostic Value of Clot Burden Score in Acute Ischemic Stroke after Reperfusion Therapies: A Systematic Review and Meta-Analysis

Clot burden score (CBS) was designed to weight the thrombus status in cerebral anterior circulation. We performed a systematic review and meta-analysis to investigate the prognostic value of CBS in acute ischemic stroke (AIS) patients undergoing reperfusion therapies.We searched relevant databases for eligible articles reporting CBS in AIS patients. The effect sizes of good functional outcome, recanalization, or hemorrhagic transformation (HT) were pooled with random-/fixed-effect models. Sensitivity analyses and heterogeneity tests were performed.Fifteen eligible studies enrolling 3302 AIS patients undergoing reperfusion therapies were included. AIS patients with per 1-point increase CBS were associated with good functional outcome (pooled odds ratio [OR]: 1.15, 95% confidence interval [CI]: 1.09-1.20) and high rate of recanalization (pooled OR: 1.27, 95% CI: 1.14-1.40). Results from categorical groups indicated high CBS at baseline was associated with higher likelihood of good functional outcome (pooled OR: 1.59, 95% CI: 1.30-1.94) and superior recanalization rates (pooled OR: 2.53, 95% CI: 1.79-3.57). Further stratified analyses showed in intravenous thrombolysis (IVT) alone group, increasing CBS was associated with good functional outcome (continuous pooled OR: 1.18, 95% CI: 1.10-1.27; categorical pooled OR: 3.38, 95% CI: 2.01-5.69) or recanalization (categorical pooled OR: 4.13, 95% CI: 2.00-8.51), but not in endovascular therapy alone group. No significant association was found between CBS and HT.CBS could be a predictor for AIS after reperfusion therapies in functional outcome and successful recanalization particularly in patients receiving IVT alone; while CBS might not be a predictor for HT.