Trends in the Effectiveness of Endovascular Recanalization for Acute Stroke: Is a Change Taking Place?

Abstract

Background: Despite recent technical advances in endovascular recanalization, there is skepticism regarding its clinical effectiveness compared with intravenous thrombolysis for treating acute ischemic stroke. We aimed to delineate its effectiveness and safety and their change over time. Methods: Using a prospective, multicenter stroke registry database, we identified 872 patients with ischemic stroke who underwent recanalization therapy with intravenous thrombolysis alone (IVT; n = 533) or endovascular recanalization with or without intravenous thrombolysis (EVT; n = 339) between April 2008 and January 2012. All subjects had National Institute of Health Stroke Scale score of 10 or more and arrived at the hospital within 4.5 hours of onset. Propensity score was used to address baseline imbalances between treatment groups, but balance adjustment was not performed for subgroup analyses. Results: The primary outcome was modified Rankin Scale score of 0-2 at discharge. The year-by-year effectiveness and safety of EVT and IVT were compared. Before 2010, the primary outcome was not associated with the recanalization method. However, in 2011, EVT increased the odds of having a primary outcome compared with IVT (adjusted odds ratio [OR], 1.87; 95% confidence interval [CI], 1.08-3.23). In 2011, EVT was superior to IVT regarding the achievement of a favorable outcome at 3 months after stroke (OR, 1.99; 95% CI, 1.10-3.59). The odds of in-hospital mortality and 3-month mortality were not different over 4 years. Conclusions: There might have been a change in the effectiveness of endovascular recanalization compared with intravenous thrombolysis, but the results remain tentative until prospectively evaluated.