Change in Stroke Treatment Guidelines
New treatment guidelines for ischemic stroke have been issued by the American Stroke Association expanding the window of treatment for clot removal from 6 to 24 hours based on brain imaging in select patients and expanding eligibility for clot busting drugs like TPA. It is projected that one out of three stroke patients could fully recover, a significant lowering of the risk of disability.
The revision was based on two studies, both published in the New England Journal of Medicine. First was the DAWN study which expanded the treatment window to 24 hours and then the DEFUSE3 study which followed up and expanded the work. The DEFUSE 3 study looked at 182 people in 38 medical centers who suffered the kinds of blockages in brain arteries that cause 50 to 60 percent of deaths and the most severe kinds of disabilities. About half received typical care, involving blood pressure medication, blood thinners and other medical interventions. The other half had images taken and the clot removal procedure known as a “thrombectomy , as well as medications.
The key is the imaging software developed at Stanford called RAPID which analyzes perfusion CT or MRI scans to look for significant areas of blood flow in the brain allowing doctors to determine what tissue is salvageable. Dr. Gregory W. Albers, a professor of Neurology at Stanford relates that we were wrong in how we have thought about how strokes evolve. While some brain tissue dies in a stroke, collateral blood vessels temporarily take over feeding a larger areas that is also starved for blood and oxygen giving doctors many more hours to save tissue that they previously believed. The adage long held that “time is brain” – that millions of neurons die each minute after stroke must be reconsidered. The diagnostic test can be read on a cellphone identifying dead and damaged tissue.
The results among the 182 persons were both reduction in death and disability. Fourteen percent of those who had thrombectomies died, compared to twenty-six percent in the medical therapy group. Forty-five percent escaped severe disabilities and were able to resume normal life with some deficits.
This is truly a game changer in the treatment of ischemic stroke. We are fortunate to have both primary and comprehensive stroke centers in the Coachella Valley.