Post-licensed 1-year experience of systemic thrombolysis with tissue plasminogen activator for ischemic stroke in a Japanese neuro-unit

Objective In Japan, intravenous thrombolysis with tissue plasminogen activator (tPA) for ischemic stroke within 3 h of onset was officially approved in October 2005. Methods We report initial 1-year clinical experience of intravenous alteplase at 0.6 mg/kg in a Japanese neuro-unit. Results Twenty patients received intravenous tPA, corresponding to 12% of all ischemic strokes (n =166) and 38% of ischemic strokes within 3 h of onset (n =52). The mean age was 68 years old and 15% had pre-morbid dependency with modified Rankin Scale (mRS) of 3 or 4. The median baseline National Institute of Health Stroke Scale score was 19 points (range; 5–37). Average time from stroke onset to tPA delivery was 136 min (range; 87–180). Of 18 (90%) patients receiving pretreatment vascular imaging, 16 (80%) patients had a large arterial occlusion. At 3 months, excellent outcome with mRS of 0 or 1 was 25%, and good outcome with mRS of 0–2 was 35%. One patient (5%) developed symptomatic intracranial hemorrhage within 36 h. Mortality rate was 15%. Conclusions Intravenous tPA within 3 h was safe and feasible, and possibly effective in clinical practice. The higher stroke severity in our cohort precluded to compare the sufficient effectiveness with clinical trials. In Japan, a post-licensed national surveillance is currently under way.