Tissue Plasminogen Activator Thrombolytic Therapy for Acute Ischemic Stroke in 4 Hospital Groups in Japan

In October 2005 in Japan, the recombinant tissue plasminogen activator (tPA) alteplase was approved for patients with acute ischemic stroke within 3 hours of onset at a dose of 0.6 mg/kg. The present study was undertaken to assess the safety and efficacy of alteplase in Japan. Between October 2005 and December 2009, a total of 114 consecutive patients admitted to 4 hospitals received intravenous tPA within 3 hours of stroke onset. Clinical backgrounds and outcomes were investigated. The patients were divided into 2 chronological groups: an early group, comprising 45 patients treated between October 2005 and December 2007, and a later group, comprising 69 patients treated between January 2008 and December 2009. The mean time from arrival at the hospital to the initiation of treatment was significantly reduced in the later group, from 82.6 minutes to 70.9 minutes. Intracerebral hemorrhage (ICH) occurred in 26 patients (22.8%); compared with patients without ICH, these patients had a significantly higher prevalence of cardiogenic embolism (88.5% vs 58.0%); greater warfarin use (26.8% vs 6.8%); higher mean National Institutes of Health Stroke Scale (NIHSS) scores on admission (16 vs 10), at 3 days after admission (14 vs 5), and at 7 days after admission (13.5 vs 3); and a lower Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Score (7.8 vs 9.1). Patients who received edaravone had a higher prevalence of cardiogenic embolism (70.9% vs 36.4%), a higher recanalization rate (77.7% vs 36.4%), and lower NIHSS scores on admission and at 3 and 7 days after admission compared with those who did not receive edaravone. Our data suggest that administration of intravenous alteplase 0.6 mg/kg within 3 hours of stroke onset is safe and effective, that the NIHSS and Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Score are useful predictors of ICH after tPA administration, and that warfarin-treated patients are more likely to develop symptomatic ICH despite an International Normalized Ratio <1.7.