The Interventional Management of Stroke (IMS) II Study

Background and Purpose— The purpose of this study was to further investigate the feasibility and safety of a combined intravenous and intra-arterial approach to recanalization for ischemic stroke.Methods— Subjects, ages 18 to 80, with a baseline NIHSS ≥10 had intravenous recombinant tissue plasminogen activator (rt-PA) started (0.6 mg/kg over 30 minutes) within 3 hours of onset. For subjects with an arterial occlusion at angiography, additional rt-PA was administered via the EKOS micro-infusion catheter or a standard microcatheter at the site of the thrombus up to a total dose of 22 mg over 2 hours of infusion or until thrombolysis.Results— The 81 subjects had a median baseline NIHSS score of 19. The median time to initiation of intravenous rt-PA was 142 minutes as compared with 108 minutes for placebo and 90 minutes for rt-PA–treated subjects in the NINDS rt-PA Stroke Trial (P <0.0001). The 3-month mortality in IMS II subjects was 16% as compared with the mortality of placebo (24%) and rt-PA–treated subjects (21%) in the NINDS rt-PA Stroke Trial. The rate of symptomatic intracerebral hemorrhage in IMS II subjects (9.9%) was not significantly different than that for rt-PA treated subjects in the NINDS t-PA Stroke Trial (6.6%). IMS II subjects had significantly better outcomes at 3 months than NINDS placebo-treated subjects for all end points (OR ≥2.7) and better outcomes than NINDS rt-PA–treated subjects as measured by the Barthel Index and Global Test Statistic.Conclusions— A randomized trial of standard intravenous rt-PA as compared with a combined intravenous and intra-arterial approach is warranted and has begun.