• An interesting article
• All this time we have been following the dictum 'time is brain' although in practice a lot of patients have been benefited by thrombolysis after 6 hours. No the MERCI collaboratos have come out with with data to prove the same. A big thumbs up for them...It not only ahall pave the path for more patient oriented work, but also alter our thinking of the pathophysiology of stroke and the path our research should take.
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• Original Contributions

Effect of Time to Reperfusion on Clinical Outcome of Anterior Circulation Strokes Treated With Thrombectomy

Pooled Analysis of the MERCI and Multi MERCI Trials

1. Raul G. Nogueira, MD; 
2. Wade S. Smith, MD, PhD; 
3. Gene Sung, MD;
4. Gary Duckwiler, MD; 
5. Gary Walker, PhD; 
6. Robin Roberts, BSc, MSc;
7. Jeffrey L. Saver, MD; 
8. David S. Liebeskind, MD 
9. on Behalf of the MERCIMulti MERCI Writing Committee

+Author Affiliations

1. From the Departments of Neurology, Neurosurgery, and Radiology (R.G.N.),
2. Emory University School of Medicine, Marcus Stroke & Neuroscience Center,
3. Grady Memorial Hospital, Atlanta, GA; Department of Neurology (W.S.S.), University of California,
4. San Francisco, CA; Department of Neurology (G.S.), University of Southern California, Los Angeles,
5. CA; Department of Interventional Neuroradiology (G.D.), University of California, Los Angeles,
6. CA; Division of Clinical Research (G.W.), Concentric Medical Inc, Mountain View, CA;
7. Department of Clinical Epidemiology & Biostatistics (R.R.), McMaster University, Hamilton,
8. ON, Canada; Department of Neurology (J.L.S., D.S.L.), University of California, Los Angeles, CA.

1. Correspondence to Raul G. Nogueira, MD, Emory Faculty Office Building 80 Jesse Hill Dr. SE, Room 398, Atlanta, GA 30303. E-mail rnoguei@emory.edu

Abstract

Background and Purpose—Previous studies have demonstrated a strong correlation between treatment time and outcomes after intravenous recombinant tissue-type plasminogen activator. However, the temporal profile of ischemia may vary according to the level of occlusion, and it is likely that more proximal occlusions have a more variable temporal course than their distal counterparts. We sought to establish how time influences outcomes in anterior circulation proximal arterial occlusions.

Methods—All patients from the MERCI/Multi MERCI trials with intracranial internal carotid artery and/or middle cerebral artery (M1-M2 segments) occlusions who were successfully revascularized were included in univariate/multivariate analyses to define the predictors of independent functional outcomes (modified Rankin Scale score ≤2) and mortality at 90 days. The effect of time to reperfusion on outcomes was calculated after adjustment for age, baseline National Institutes of Health Stroke Scale, and glucose levels.

Results—A total of 175 patients presenting with internal carotid artery/M1/M2 occlusions were revascularized. There was no definite association between time (to treatment or reperfusion) and outcomes in the unadjusted analysis. Baseline National Institutes of Health Stroke Scale score and age were independent predictors of independent outcome and mortality. High glucose demonstrated a strong trend toward worse outcomes. After adjustment for age, baseline National Institutes of Health Stroke Scale score, and glucose, there was a strong trend toward fewer independent outcomes with later reperfusion times. Notably, 40% of the patients reperfused at ≥6.9 hours achieved independent functional outcomes.

Conclusions—Time (to treatment or reperfusion) is only one of the many variables that may impact outcome in proximal arterial occlusions strokes. Reperfusion therapies should be started promptly, but our findings also suggest that stroke patients presenting at later time points may still benefit.

Key Words:

• stroke outcomes
• thrombectomy