Intravenous Recombinant Tissue Plasminogen Activator in Acute Stroke

Severe focal ischemia leads to neuronal death within minutes. Due to the cerebral collateral network, in most instances occlusion of a major intracranial artery causes variable degrees of ischemia and oxygen supply within different parts of the vessel’s territory. The ability of brain tissue to survive under ischemic conditions is time-dependent [4]. Restoring cerebral blood flow by recanalization of the occluded artery may help to decrease the extent of ischemic necrosis. Recently, new thrombus-selective thrombolytic agents such as recombinant tissue plasminogen activator (rt-PA) and single-chain urokinase plasminogen activator (scu-PA) have become available and are being successfully used in the treatment of ischemic heart disease. Encouraged by reports of successful arterial recanalization associated with favorable clinical outcome following intra-arterial infusion of streptokinase or urokinase [2, 3, 8–10], we studied the efficacy and safety of intravenous rt-PA in patients with acute thromboembolic vertebrobasilar and middle cerebral artery stroke. The purpose of this study was to find the dosage of alteplase (rt-PA) which is safe with respect to intracranial hemorrhage and effective with respect to thrombolysis and clinical outcome in preparation for a controlled study.