Symptomatic intracerebral hemorrhage among eligible warfarin-treated patients receiving intravenous tissue plasminogen activator for acute ischemic stroke.

OBJECTIVE To determine whether warfarin-treated patients with an international normalized ratio less than 1.7 who receive intravenous tissue plasminogen activator for acute ischemic stroke are at increased risk for symptomatic intracerebral hemorrhage. DESIGN Retrospective study. SETTING Academic hospital. PATIENTS Consecutive patients with acute ischemic stroke who are treated with intravenous tissue plasminogen activator. MAIN OUTCOME MEASURE Symptomatic intracerebral hemorrhage. RESULTS One hundred seven patients were included (mean age, 69.2 years; 43.9% men; median National Institutes of Health Stroke Scale score, 14; median onset-to-treatment time, 140 minutes; baseline warfarin use, 12.1%). The median international normalized ratio was 1.04 (range, 0.82-1.61). The overall rate of symptomatic intracerebral hemorrhage was 6.5%, but it was nearly 10-fold higher among patients taking warfarin compared with those not taking warfarin at baseline (30.8% vs 3.2%, respectively; P = .004). Baseline warfarin use remained strongly associated with symptomatic intracerebral hemorrhage (P = .004) after adjusting for relevant covariates, including age, atrial fibrillation, National Institutes of Health Stroke Scale score, and international normalized ratio. CONCLUSIONS Despite an international normalized ratio less than 1.7, warfarin-treated patients are more likely than those not taking warfarin to experience symptomatic intracerebral hemorrhage following treatment with intravenous tissue plasminogen activator. Larger studies in this subgroup are warranted.