Barriers in Acute Stroke Therapy: Evolution of Endovascular Interventions for Stroke

Author(s): Sun Jing

Whether interventional approaches to stroke neurology have lagged behind those aimed at heart attack for reasons biological or practical are topics for another day. However, the balance has changed. Tissue plasminogen activator (tPA) was first approved in the United States for intravenous administration to patients with acute stroke in 1996, and a study for catheter-directed intra-arterial infusion of a thrombolytic agent for this indication was first published in 1998. The first positive randomized controlled study using mechanical thrombectomy devices for stroke came from the Netherlands just last year, and results from 4 additional trials published in 2015 support combined treatment with tPA and catheterbased thrombectomy [1]. In the recent positive stroke trials, removable devices consisting of self-expanding, clot-retrieving stents achieved higher rates of recanalization than earlier methods of thrombus extraction, representing the first effective new treatment for stroke in nearly 20 years. The measures employed in these studies have lengthened the time-totreatment window and help guide the selection of patients who benefit most from acute endovascular intervention [2]. With absolute benefits substantially greater than systemic intravenous thrombolysis alone, the combination of intravenous tPA and endovascular therapy have improved outcomes for selected patients who receive endovascular treatment within 6 h of symptom onset [3].