For stroke patients with potentially salvageable ischemic brain tissue, can thrombectomy from 6 hours to 16 hours after onset of symptoms result in improved outcomes?

Patients presenting with acute ischemic stroke from occlusion of a large vessel cerebral artery and who have imaging evidence of reversible ischemic brain tissue can benefit from thrombectomy even after 6 hours from onset of symptoms. (LOE = 1b)

Albers GW, Marks MP, Kemp S, et al, for the DEFUSE 3 Investigators. Thrombectomy for stroke at 6 to 16 hours with selection for perfusion imaging. N Engl J Med 2018; Jan 24. doi:10.1056/NEJMoa1713973. [Epub ahead of print] Nogueira RG, Jadhav AP, Haussen DC, et al, for the DAWN Trial Investigators. Thrombectomy 6 to 24 hours after stroke with a mismatch between deficit and infarct. N Engl J Med 2018;378(1):11-21.  [PMID:29364767]

Randomized controlled trial (nonblinded)

Government

Concealed

Inpatient (any location) with outpatient follow-up

For patients with internal carotid artery and/or proximal middle cerebral artery occlusion, endovascular thrombectomy performed within 6 hours of onset of stroke symptoms has been shown to be effective. For the Albers et al study, investigators enrolled stroke patients who presented 6 hours to 16 hours after onset of symptoms and had evidence of potentially reversible ischemic brain tissue on imaging studies. Patients were randomized, using concealed allocation, to receive thrombectomy plus standard medical care (n = 92) or standard medical care alone (n = 90). Baseline characteristics were balanced in the 2 groups and approximately half the patients in each group awoke from sleep with symptoms of stroke. The primary outcome was the score on the 90-day modified Rankin scale (range 0 - 6; higher scores indicate greater disability). The thrombectomy group had a signficantly more favorable distribution of Rankin scores than the control group. Forty-five percent of patients in the thrombectomy group were functionally independent (modified Rankin score 0 - 2 at 90 days) as compared with only 17% of the control group (relative risk 2.67; 95% CI 1.60 - 4.48; P < .001). For safety outcomes, 90-day mortality was lower in the thrombectomy group (14% vs 26%; P = .05) and there was no significant difference detected in symptomatic intracranial hemorrhage or serious adverse events between the 2 groups. The Nogueira et al study is an industry-funded trial that showed similar findings in patients with disproportionately severe clinical deficits relative to infarct volume on imaging who presented 6 hours to 24 hours after onset of stroke symptoms. In this trial, patients who underwent thrombectomy plus standard medical care had better functional outcomes at 90 days than those who received medical care alone.