Reperfusion after 4·5 hours reduces infarct growth and improves clinical outcomes

Wiley: 11/21/13

The currently proven time window for thrombolysis in ischemic stroke is 4·5 h. Beyond this, the risks and benefits of thrombolysis are uncertain.

To determine whether thrombolysis and reperfusion were beneficial after 4·5 h, we examined clinical and radiological outcomes in patients treated with tissue plasminogen activator or placebo within 4·5–6 h, using data from the Echoplanar Imaging Thrombolytic Evaluation Trial.

In the Echoplanar Imaging Thrombolytic Evaluation Trial, ischemic stroke patients presenting three to six-hours after stroke onset were randomized to tissue plasminogen activator or placebo, without knowledge of magnetic resonance imaging results. This analysis was restricted to patients treated between 4·5 and 6 h. The effect of tissue plasminogen activator and reperfusion on infarct growth between baseline diffusion-weighted imaging and day 90 T2 imaging was assessed, along with good neurological outcome (≥8 point reduction or reaching 0–1 at 90 days on National Institutes of Health Stroke Scale) and functional outcome (modified Rankin scale). The effect of tissue plasminogen activator on reperfusion was also analyzed. Read More