Category: Pharmacology & Therapeutics
Keywords: alteplase, tPA, warfarin, INR, ischemic stroke (PubMed Search)
Issue 1: Mean INR in study patients was only 1.22 (median 1.2). An INR of 1.2 represents very little actual anticoagulation.
Issue 2: In the small subgroup of patients with INR 1.5 to 1.7 (n = 269) there was a higher risk of ICH (7.8%), but did not reach statistical significance (it was significant in the unadjusted risk population).
Bottom line: Patients with INRs < 1.5 may be ok to receive tPA. Patients with INRs 1.5 or greater need further study.
Xian Y, Liang L, Smith EE, et al. Risk of Intracranial Hemorrhage Among Patients With Acute Ischemic Stroke Receiving Warfarin and Treated with Intravenous Tissue Plasminogen Activator. JAMA. 2012;307(24):2600-8.
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