The Stroke ‘Window’ for Treatment Opens a Crack . . .

It’s been emphasized over and over again that time is a critical issue in the management of acute ischemic stroke. It’s recommended that clot-busting medication is started within 3 hours of the first stroke symptoms. Numerous studies of the benefits of tissue plasminogen activator (Activase®) show that they are time-related: if given within the first 90 minutes the chances of a favorable outcome are tripled, whereas there is no benefit after 6 hours. It seems the 3-hour ‘window’ set by the FDA when Activase was first approved can be extended, according to a recent report in the journal Lancet.

Swedish researchers analyzed data from 12,500 ischemic stroke patients included in the International Stroke Thrombolysis Registry. They compared 664 patients given Activase between 3 and 4½ hours after first symptoms with 11,850 patients treated within 3 hours. The average time from first symptom to Activase was 195 minutes in the first group vs. 140 minutes in the second.

There were no significant differences between the 0 – 180 minutes and 0 – 270 minutes with respect to mortality, independence (a measure of disability), or a brain hemorrhage (a known but rare side effect of Activase).

The bottom line: Activase can be given up to 4½ hours after the first symptom without significant lesser activity or greater risk of a serious side effect than when given within 3 hours. The ‘window’ is a little more open!

This doesn’t mean one should dilly-dally after a stroke is suspected. Hospitals will do their share to reduce the time between admission and the start of Activase, but patients need to make their contribution. Don’t hesitate when any of the stroke or TIA symptoms occur – call 911.