The most important factor in successful thrombolytic therapy of acute ischemic stroke is early treatment. Nonetheless, selection of appropriate candidates for thrombolysis demands a neurologic evaluation and a neuroimaging study. In addition, the use of thrombolytics for acute stroke requires a system that coordinates emergency services, stroke neurology, intensive care services, neuroimaging, and neurosurgery to provide optimal treatment.
This topic will review the use of intravenous alteplase treatment for patients with acute ischemic stroke. The evidence supporting the use of intravenous thrombolysis and other methods of restoring blood flow to salvage ischemic brain tissue is reviewed in detail separately. (See "Reperfusion therapy for acute ischemic stroke".)
Other aspects of acute ischemic stroke care are discussed elsewhere. (See "Initial assessment and management of acute stroke" and "Antithrombotic treatment of acute ischemic stroke and transient ischemic attack" and "Neuroimaging of acute ischemic stroke".)
PATIENT SELECTION AND ELIGIBILITY
Randomized, controlled trials have shown that intravenous recombinant tissue plasminogen activator (tPA or alteplase) therapy is beneficial for select patients with acute ischemic stroke who start treatment within 4.5 hours of symptom onset in expert centers. This evidence is discussed in detail separately. (See "Reperfusion therapy for acute ischemic stroke", section on 'Intravenous thrombolysis'.)
For eligible patients (table 1) with acute ischemic stroke, we recommend intravenous alteplase therapy when treatment is initiated within three hours of clearly defined symptom onset. For patients who cannot be treated in less than three hours, we suggest (ie, a weak recommendation) intravenous alteplase therapy provided that treatment is initiated within 3 to 4.5 hours of clearly defined symptom onset. These recommendations are in general agreement with current guidelines from the American Heart Association/American Stroke Association (AHA/ASA)  and the American College of Chest Physicians (ACCP) .