Arterial occlusive lesions recanalize more frequently in women than in men after intravenous tissue plasminogen activator administration for acute stroke

Background and Purpose - Previous reports suggest that women achieve better outcome than men after intravenous thrombolysis for ischemic stroke. Coagulation and fibrinolysis differ between sexes. These findings prompted us to investigate possible gender differences in arterial recanalization after intravenous tissue plasminogen activator (IV tPA). Methods - We identified 100 consecutive patients who presented with acute ischemic stroke and received IV tPA within 6 hours of onset. Only patients with large artery anterior circulation strokes, as determined by MRI/MRA or CT/CTA before treatment, who had follow-up vascular study within 72 hour after treatment were included. We compared demographics, clinical features, admission medications, symptom-to-needle and treatment-to-repeat vascular imaging times, baseline National Institutes of Health Stroke Severity score, radiological and laboratory data, stroke mechanism, and outcome between the sexes. Results - 39 patients met all inclusion/exclusion criteria (22 men and 17 women). The recanalization rate was significantly higher in women (94 % versus 59 %; P = 0.02). This difference remained statistically significant after excluding patients whose strokes were attributed to internal carotid artery occlusive lesions, and when the analysis was limited to those treated within 3 hours of stroke onset. All other confounding variables did not differ significantly between the sexes. Conclusions - In our cohort, vascular occlusive lesions were more likely to recanalize in women than men in response to IV tPA. These preliminary findings need to be validated in larger prospective studies.