Efficacy and safety of i.v. alteplase therapy up to 4.5 hours after acute ischemic stroke onset

The efficacy and safety of i.v. alteplase up to 4.5 hours after acute ischemic stroke (AIS) onset were evaluated. Stroke is the leading cause of disability in the elderly, and i.v. alteplase (recombinant tissue plasminogen activator) is the only Food and Drug Administration (FDA)-approved thrombolytic agent for the treatment of AIS. Alteplase has been shown to decrease the percentage of patients disabled by a stroke. Until recently, the use of alteplase was only recommended within 3 hours of the onset of AIS symptoms. However, two clinical trials published in 2008 demonstrated that therapy with i.v. alteplase remains safe and effective when given 3-4.5 hours after AIS onset. Although FDA has not yet approved expanding the time interval to 4.5 hours for treatment with i.v. alteplase, the American Stroke Association recently published a statement recommending administration of alteplase in eligible patients 3-4.5 hours after symptom onset. There is clinical evidence supporting the safety and efficacy of i.v. alteplase administration to eligible patients who present within 4.5 hours of AIS symptom onset. Treatment with alteplase decreases the likelihood of disability from an AIS and is not associated with an increased rate of mortality. Expanding the time window for treatment with alteplase would likely increase the percentage of AIS patients who are able to receive alteplase and thus ultimately decrease the percentage of those left disabled from an AIS. Evidence supports the safety and efficacy of i.v. alteplase administration to eligible patients within 4.5 hours of AIS symptom onset.