Background Thrombectomy is currently recommended for eligible patients with stroke who are treated within 6 hours after the onset of symptoms. Methods We conducted a multicenter, randomized, open-label trial, with blinded outcome assessment, of thrombectomy in patients 6 to 16 hours after they were last known to be well and who had remaining ischemic brain tissue that was not yet infarcted. Patients with proximal middle-cerebral-artery or internal-carotid-artery occlusion, an initial infarct size of less than 70 ml, and a ratio of the volume of ischemic tissue on perfusion imaging to infarct volume of 1.8 or more were randomly assigned to endovascular therapy (thrombectomy) plus standard medical therapy (endovascular-therapy group) or standard medical therapy alone (medical-therapy group). The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability) at day 90. Results The trial was conducted at 38 U.S. centers and terminated early for efficacy after 182 patients had undergone randomization (92 to the endovascular-therapy group and 90 to the medical-therapy group). Endovascular therapy plus medical therapy, as compared with medical therapy alone, was associated with a favorable shift in the distribution of functional outcomes on the modified Rankin scale at 90 days (odds ratio, 2.77; P<0.001) and a higher percentage of patients who were functionally independent, defined as a score on the modified Rankin scale of 0 to 2 (45% vs. 17%, P<0.001). The 90-day mortality rate was 14% in the endovascular-therapy group and 26% in the medical-therapy group (P=0.05), and there was no significant between-group difference in the frequency of symptomatic intracranial hemorrhage (7% and 4%, respectively; P=0.75) or of serious adverse events (43% and 53%, respectively; P=0.18). Conclusions 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. (Funded by the National Institute of Neurological Disorders and Stroke; DEFUSE 3 ClinicalTrials.gov number, NCT02586415 .).
Landmark study worth considering in conjunction with the recently published DAWN trial. This is a small RCT with encouraging results but taken together with DAWN is suggestive of some very dramatic implications for emergency care in urban and non-urban settings. Cost-effectiveness remains uncertain. Also, the question of how feasible (and reproducible) this intervention is over a wide range of resource settings remains unanswered. Similarly, can we afford it as a society?
This is great information for internists when they are speaking to patients at risk for a stroke, but I don't think it will change the way they manage patients in the outpatient or hospital setting.
As a hospitalist, this well done RCT now extends the benefits of endovascular therapy for acute ischemic stroke to a new population. They must be highly selected, but this will afford many stroke victims who present beyond 6 hours of symptom onset a chance at a better clinical outcome.
Like the studies before such as MRClean, Escape, Revascat, Swift prime led to the Grade A recommendation for ET therapy, I see this happening very soon. As a hospitalist constantly involved in Code Gray (stroke Rapid response) teams, it’s important to be familiar with ET and new guidelines as this will change patient outcomes significantly. This is a milestone study and has great future implications in patient care. Methodology is well defined with strong results.
This trial confirms the benefits of thrombectomy seen in the DAWN trial for stroke patients who present late after stroke onset, or have stroke symptoms upon awakening with an "ischemic penumbra" of an at-risk brain.
Another study using another technique that shows that we can use "tissue windows" instead of "time windows" to treat ischemic stroke.