Effect of warfarin withdrawal on thrombolytic treatment in patients with ischaemic stroke

Background and purpose: Abruptly discontinuing warfarin may induce a rebound prothrombotic state. Thrombolytic agents may also paradoxically induce prothrombotic conditions, which include platelet activation and thrombin generation. Therefore, prothrombotic states may be enhanced by withdrawing warfarin in patients under thrombolytic treatment. This study was aimed to determine whether patients with warfarin withdrawal have different clinical outcomes from those without warfarin use after thrombolytic treatment. Methods: A total of 148 consecutive patients with atrial fibrillation who were not on anticoagulants at admission and who received thrombolysis were included in this study. We compared the outcomes between a warfarin withdrawal group and a no-warfarin group. Results: Fourteen patients (9.5%) were included in the warfarin withdrawal group. Although baseline National Institute of Health Stroke Scale (NIHSS) scores, recanalization rates, and hemorrhage frequencies did not differ between the groups, the warfarin withdrawal group showed poorer outcomes. Increased NIHSS scores during the first 7 days were more frequent in the warfarin withdrawal group (57.1% vs. 26.9%, P = 0.029). The median percent improvement in NIHSS scores at 24 h after thrombolysis was also lower in the warfarin withdrawal group. After adjusting for covariates, warfarin withdrawal was a strong predictor of poor functional outcome at 3 months (modified Rankin score >= 3) (odds ratio, 17.067, 95% CI 2.703-107.748). Conclusions: Discontinuing warfarin was associated with early neurologic deterioration and poor long-term outcomes after thrombolytic treatment.