Endovascular thrombectomy after large-vessel ischemic stroke: a meta-analysis of individual patient data from five randomised trials
In 2015, five randomized trials showed efficacy of endovascular thrombectomy over medical care in patients with acute ischemic stroke caused by large vessel occlusion (LVO) of arteries of the proximal anterior circulation. A recent publication in the Lancet from the trial investigators from these trials, reported the pooled patient analysis of these studies to determine whether therapy is efficacious across diverse populations. Individual data for 1287 patients (634 assigned to endovascular thrombectomy, 653 assigned to control) was assessed in mixed effects meta-analysis. Endovascular thrombectomy led to significantly reduced disability at 90 days compared with control (adjusted cOR 2.49). The number needed to treat with endovascular thrombectomy to reduce disability by at least one level on mRS for one patient was 2.6. Subgroup analysis of the primary endpoint showed no heterogeneity of treatment effect across prespecified subgroups for reduced disability. Effect sizes favoring endovascular thrombectomy over control were significant in several strata of special interest, including in patients aged 80 years or older (cOR 3.68), those randomized more than 300 min after symptom onset (1.76), and those not eligible for intravenous alteplase (2.43). Mortality at 90 days and risk of parenchymal hematoma and symptomatic intracranial hemorrhage did not differ between populations. These studies provide resounding evidence for endovascular thrombectomy over standard medical care in patients with acute ischemic stroke caused by LVO of the anterior circulation. These findings will have global implications on structuring systems of care to provide timely treatment to patients with acute ischemic stroke due to LVO.