Subtherapeutic warfarin is not associated with increased hemorrhage rates in ischemic strokes treated with tissue plasminogen activator.

University of Toronto, Toronto Western Hospital, Department of Medicine, Division of Neurology, 399 Bathurst Street, 5th Floor, West Wing, room 443, Toronto, Ontario M5T 2S8, Canada.
Stroke (Impact Factor: 6.02). 02/2011; 42(4):1041-5. DOI: 10.1161/STROKEAHA.110.599183
Source: PubMed

ABSTRACT Concern exists that preadmission warfarin use may be associated with an increased risk of intracerebral hemorrhage in patients with ischemic stroke receiving intravenous tissue plasminogen activator, even in those with an international normalized ratio <1.7. However, evidence to date has been derived from a small single-center cohort of patients.
We used data from Phase 3 of the Registry of the Canadian Stroke Network. We compared the rates of post-tissue plasminogen activator hemorrhage, including any intracerebral hemorrhage, symptomatic intracerebral hemorrhage, and gastrointestinal hemorrhage in patients with and without preadmission warfarin use. For those receiving warfarin, we restricted the analysis to patients with an international normalized ratio <1.7 on presentation. Secondary outcomes included functional status and mortality. Multivariate analyses were performed to adjust for other prognostic factors.
Our cohort included 1739 patients with acute ischemic stroke treated with intravenous tissue plasminogen activator of whom 125 (7.2%) were receiving warfarin before admission and had an international normalized ratio <1.7. Preadmission warfarin use was not associated with any secondary intracerebral hemorrhage (OR, 1.2; 95% CI, 0.7 to 2.2), symptomatic intracerebral hemorrhage (OR, 1.1; 95% CI, 0.5 to 2.3), or gastrointestinal hemorrhage (OR, 1.1; 95% CI, 0.2 to 5.6). Multivariate analysis showed that preadmission warfarin use was independently associated with a reduced risk of poor functional outcome (OR, 0.6; 95 CI, 0.3 to 0.9), but not with in-hospital mortality (OR, 0.6; 95% CI, 0.3 to 1.0).
The results from the present study suggest that tissue plasminogen activator treatment appears to be safe in patients with acute ischemic stroke taking warfarin with an international normalized ratio <1.7 and may reduce the risk of poor functional outcome.

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    ABSTRACT: Background The indications and contraindications for intravenous (IV) recombinant tissue plasminogen activator (rtPA) use in ischemic stroke can be confusing to the practicing neurologist. Here we seek to describe practice patterns regarding decision-making among US stroke clinicians. Methods Stroke clinicians (attending and fellow) from the 8 National Institutes of Health SPOTRIAS (Specialized Programs of Translational Research in Acute Stroke) centers were asked to complete a survey ahead of the 2012 SPOTRIAS Investigators' meeting. Results A total of 51 surveys were collected (71% response rate). Most of the responders were attending physicians (68%). Only 18% of clinicians reported strictly adhering to current American Heart Association guidelines for treatment within 3 hours from symptom onset; this increased to 51% for the European Cooperative Acute Stroke Study (ECASS) III criteria in the 3 to 4.5 hours time frame. All clinicians treat eligible patients in the 3 to 4.5 hours time frame. The great majority will recommend rtPA in the following scenarios: (1) elderly individuals irrespective of age (97%); (2) severe stroke irrespective of National Institutes of Health Stroke Scale (NIHSS) (95%); or (3) suspected stroke with seizures at symptom onset (91%). None recommended rtPA in the setting of an international normalized ratio >1.7. Most clinicians defined mild strokes as an exclusion based on the perceived disability of the deficit (80%) rather than on a specific NIHSS threshold. Conclusions Most surveyed stroke clinicians seem to find that the current IV rtPA eligibility criteria for the 3-hour time frame too restrictive. All would recommend rtPA to eligible patients in the 3 to 4.5 hours time frame despite the absence of an U.S. Food and Drug Administration (FDA)-approved indication.
    Journal of Stroke and Cerebrovascular Diseases 09/2014; · 1.99 Impact Factor
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    ABSTRACT: This study aimed to assess the risk and benefit of tissue-type plasminogen activator treatment after oral anticoagulation with rivaroxaban or apixaban compared with warfarin or placebo.
    Stroke 07/2014; 45(8). · 6.02 Impact Factor
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    ABSTRACT: This article reviews some of the current literature in support or against extension of the intravenous tissue plasminogen activator window, use of intra-arterial therapy or devices, as well alternative pharmacologic therapies that may extend the window for treatment of patients with acute ischemic stroke, with consideration of the relative risk of thrombolytic complications, factors for worse outcomes, and unclear stroke onset, as seen in patients with wake-up stroke. The issue of newer concomitant antithrombotic therapies as they affect the decision for acute ischemic stroke thrombolytic therapy is also explored.
    Neurologic Clinics 08/2013; 31(3):677-704. · 1.61 Impact Factor


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May 16, 2014