Extended Time Window for Stroke Treatment. The Public Gets the Wrong Message
The recent presentation and publication of two clinical trials supporting the effective treatment of ischemic stroke as long as 24 hours after onset have been widely disseminated by the press. Articles have correctly hailed this as a major advance in stroke diagnosis and treatment. Both the DEFUSE 3 and DAWN trials have robust treatment effects, in some cases stronger than for patients treated within 6 hours. The studies are presented as a dramatic advance which could be misunderstood as benefiting all stroke patients.
The Washington Post reported “New research will radically change response to strokes”. The article makes the following statement: “The new findings suggest they (doctors) may have as long as 16 hours in many cases”. It is the word many that can be misleading to anyone reading this message. The tone of most articles emphasizes that it will now be possible to treat stroke patients as long as 24 hours after symptoms. What is not generally stated, however, is that this approach will only benefit a minority of stroke patients, and that for most strokes “Time is Brain” still applies, and that a person experiencing stroke symptoms should get to a stroke center as soon as possible to have an opportunity to preserve brain tissue which is at risk.
A patient told me this past week that “I am up to date with the news. I know that I can take 24 hours to get to the hospital if I am having a stroke”. I am certain that this was not the intended message, but this is the way it has been perceived. If I had any doubt, last night a member of our local volunteer EMS called ahead to our ED with a patient whose stroke started 12 hours earlier, commenting that he knew there was still ‘plenty of time’.
The most important information to be derived from these studies is that not all strokes progress at the same rate, and there are now diagnostic studies to find the patients who have blockage of major arteries, but have not yet sustained major damage. These are the patients that were shown to benefit in these treatment trials. And the fact that they can greatly benefit from treatment so late is indeed revolutionary.
These late treatment trials will indeed lead to widespread changes in stroke care, especially in the treatment of patients who wake up with stroke symptoms, and have previously been automatically excluded from treatment. Hospitals in these studies utilized specialized CT scans, with software for automatic analysis that is not yet widely available. As stroke care advances, the ability to get the right patients to centers that can perform the advanced interventional therapies will become widespread. But for now, the extended time windows for treatment will only be available to a small minority of stroke patients.