Stroke patients on warfarin can be safely treated with clot-busting drug

Acute ischemic stroke patients taking the blood thinner warfarin can be treated safely with the clot-busting drug tissue plasminogen activator (tPA), according to research presented at the American Heart Association's Quality of Care and Outcomes Research Scientific Sessions 2012. "Although it's the only drug approved by the Food and Drug Administration to treat acute ischemic stroke, tPA is underused among patients on home warfarin therapy mainly because of the fear that it will cause bleeding," said Ying Xian, M.D., Ph.D., the study's lead author and a research fellow at Duke Clinical Research Institute, in Durham, N.C. Xian and colleagues used data from the American Heart Association/American Stroke Association's Get With The Guidelines®-Stroke registry to evaluate tPA safety in warfarin-treated patients who had an ischemic stroke, which occurs when a blood vessel to the brain becomes blocked. The data was from 23,437 ischemic stroke patients treated with tPA in 1,203 Get With The Guidelines-Stroke hospitals between April 2009 and June 2011. Almost 8 percent (1,802) of patients were taking warfarin prior to admission. Patients on warfarin prior to hospitalization for an ischemic stroke tended to be older (77 years vs. 71 years), had more illnesses at the time of their strokes and had more severe strokes than patients not on warfarin. Nevertheless, the risk of severe bleeding from brain hemorrhage was similar among stroke patients who received tPA after stroke, regardless of whether they were on warfarin. The researchers also didn't find notable differences between warfarin and non-warfarin patients when they compared risks of tPA-related complications or in-hospital death after tPA. "Our study suggests tPA is not associated with excessive bleeding or death among warfarin patients, when used according to American Heart Association/American Stroke Association guidelines," Xian said. "tPA has been shown to minimize brain damage and disability from stroke and should not be withheld from these patients." The study is the largest on the safety of tPA in warfarin-treated patients who meet clinical guideline criteria. However, Xian said they didn't measure functional, neurological or long-term results of tPA treatment.