Impact of Onset-to-Reperfusion Time on Stroke Mortality: A Collaborative Pooled Analysis

Study Questions:

What is the impact of symptom onset-to-reperfusion time on mortality among patients presenting with stroke?


The authors performed a collaborative pooled analysis of seven endovascular databases and assessed the impact of onset-to-reperfusion time in large-artery occlusion (internal carotid artery or middle cerebral artery) on outcomes. Successful reperfusion was defined as complete or partial restoration of blood flow within 8 hours from symptom onset. Primary outcome for this analysis was 90-day all-cause mortality. Secondary outcomes included 90-day favorable outcome (modified Rankin Scale score, 0-2), 90-day excellent outcome (modified Rankin Scale score, 0-1), and occurrence of any intracerebral hemorrhage within 24-36 hours after treatment.


The study cohort was comprised of 480 cases with successful reperfusion (median time, 285 minutes), of whom 120 presented with internal carotid artery occlusion and 360 with isolated middle cerebral artery occlusion. Increasing onset-to-reperfusion time was associated with an increased rate of mortality and intracerebral hemorrhage, and with a decreased rate of favorable and excellent outcomes. There was no heterogeneity across studies. The adjusted odds ratio for each 30-minute time increase was 1.21 (95% confidence interval [CI], 1.09-1.34; p < 0.001) for mortality, 0.79 (95% CI , 0.72-0.87) for favorable outcome, 0.78 (95% CI, 0.71-0.86) for excellent outcome, and 1.21 (95%, 1.10-1.33) for intracerebral hemorrhage.


The authors concluded that delay in reperfusion is associated with an increase in mortality in patients with large strokes.


Delay in pharmacological reperfusion is associated with increasing brain injury, and it is not surprising that the time from symptom onset-to-reperfusion is a strong predictor of mortality among patients treated with endovascular therapy. Strategies to shorten onset-to-treatment time need to be developed to improve outcome of stroke.

Clinical Topics: Vascular Medicine

Keywords: Middle Cerebral Artery, Time-to-Treatment, Stroke, Brain Injuries, Infarction, Middle Cerebral Artery, Carotid Artery, Internal, Cerebral Hemorrhage

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