Skip to content

Major News in Stroke Treatment

New guidelines increase the window for effective clot busting

clock face with a blurry red second hand

iStockphoto/Getty Images

Traditionally, doctors thought they had only six hours to resolve a clot before massive brain damage occurred. However, two new studies show that they have between 16 and 24 hours to provide treatment.

In what amounts to a sea change in stroke treatment, doctors are being told they have up to four times longer to save the lives and brains of patients suffering from the most common type of stroke.

Doctors long thought they had six hours to resolve a clot before massive brain damage occurred, but two new studies, both published in the New England Journal of Medicine, show that they have between 16 and 24 hours to perform a clot-busting thrombectomy. Determining which patients would benefit from the procedure, which involves threading a catheter through an artery to send in a clot-grabbing device, requires careful screening of brain scans to find the patients in whom a stroke's damage to brain tissue hasn't spread as quickly, or as far, as it was once assumed to do.

Both studies were presented at a stroke conference held by the American Heart Association/American Stroke Association in Los Angeles. At the meeting the organization issued treatment guidelines to reflect this new 24-hour window; the guidelines are expected to greatly increase the number of patients who are eligible for clot-busting procedures. 

“This is going to make a huge, huge difference in stroke care,” William J. Powers, M.D., the guidelines-writing group chair and chair of neurology at the University of North Carolina School of Medicine in Chapel Hill, said upon the release of the treatment protocols. The guidelines also allow for the clot-dissolving medicine Alteplase (the earlier line of treatment) to be given up to 4 1/2 hours after a stroke.

In releasing the guidelines, the association stressed that increased responsibility will now fall on hospitals that don't have access to stroke specialists to connect via methods like videoconferencing with neurologists at larger centers to evaluate and treat patients.  

The responsibilities that fall to stroke patients and their families remain the same. As always, the most important step they can take to preserve life and prevent future disability, doctors say, is calling 911 at the first signs of stroke, which include facial drooping, slurred speech and arm weakness.