Thrombolytic Therapy in Acute Ischemic Stroke.

The use of intravenous thrombolytic therapy for the treatment of patients with acute ischemic stroke is now approved in the United States, Canada, Germany, and the European Union. Guidelines published in 1996 from the American Heart Association and American Academy of Neurology committees recommended intravenous administration of recombinant tissue-plasminogen activator (rt-PA) (0.9 mg/kg; maximum of 90 mg) given in a 10% bolus, followed by an infusion lasting 60 minutes, to patients within 3 hours of onset of ischemic stroke. The recommendations stipulate that a computed tomography scan before the infusion should not show major infarction, mass effect, edema, or hemorrhage. Yet, only a small fraction of eligible patients (< 5%) have received rt-PA during the 7 years since its approval in the United States. Although effective, thrombolysis carries an important risk (5% to 10%) of brain hemorrhage and edema that can prove fatal. Many physicians and medical centers are not presently equipped or willing to give thrombolytic drugs for stroke treatment.