Current recommendations say that patients are eligible for thrombectomy within 6 hours of a stroke, but newly released results from the DEFUSE 3 trial suggest that the window of opportunity may extend up to 16 hours in certain patients. The results of the trial were published in the New England Journal of Medicine, and the trial was ended early for efficacy.
DEFUSE 3 was a randomized, open-label trial with blinded outcome assessment and was conducted at 38 US centers. Patients were randomized to either endovascular therapy (thrombectomy), medical therapy, or endovascular and medical therapy. Patients were included in the trial within 6 to 16 hours of when they were last known to be well and if they had remaining ischemic brain tissue that was not yet infarcted. The primary outcome was disability at 90 days as measured by the modified Rankin scale.
Results indicated that patients who received endovascular plus medical therapy had better functional outcomes at 90 days (45% achieved functional independence) compared with patients who received medical therapy alone (17% achieved functional independence). Also at 90 days, the mortality rate was 14% among patients in the endovascular group and 26% in the medical-therapy group. There was no significant difference between groups in serious adverse events or frequency of symptomatic intracranial hemorrhage.
“Endovascular thrombectomy for ischemic stroke 6 to 16 hours after a patient was last known to be well plus standard medical therapy resulted in better functional outcomes than standard medical therapy alone among patients with proximal middle-cerebral-artery or internal-carotid-artery occlusion and a region of tissue that was ischemic but not yet infarcted,” the researchers concluded.
The study was funded by the NIH’s National Institute of Neurological Disorders and Stroke (NINDS). In the announcement from the NIH, Walter Koroshetz, MD, Director of NINDS, said, "These striking results will have an immediate impact and save people from life-long disability or death. I really cannot overstate the size of this effect. The study shows that one out of three stroke patients who present with at-risk brain tissue on their scans improve, and some may walk out of the hospital saved from what would otherwise have been a devastating brain injury."
Albers GW, Marks MP, Kemp S. Thrombectomy for stroke at 6 to 16 hours with selection by perfusion imaging. N Engl J Med. 2018 Jan 24. doi: 10.1056/NEJMoa1713973. [Epub ahead of print]