Endovascular treatment for M2 occlusions in the era of stentrievers: A descriptive multicenter experience

© 2015, BMJ Publishing Group. All rights reserved. Background: Patients with M2 middle cerebral artery (MCA) occlusions are not always considered for endovascular treatment. Objective: To study outcomes in patients with M2 occlusion treated with endovascular procedures in the era of stentrievers. Methods: We studied patients prospectively included in the SONIIA registry (years 2011-2012) - a mandatory, externally audited registry that monitors the quality of reperfusion therapies in Catalonia in routine practice. Good recanalization was defined as postprocedure Thrombolysis in Cerebral Infarction (TICI) score 2b-3; dramatic recovery as drop in National Institutes of Health Stroke Scale (NIHSS) score >10 points or NIHSS score <2 at 24-36 h; and good outcome as modified Rankin score (mRS) 0-2 at 3 months. A 24 h CT scan determined symptomatic intracranial hemorrhage (SICH) and infarct volume. Results: Of 571 patients who received endovascular treatment, 65 (11.4%) presented an M2 occlusion on initial angiogram, preprocedure NIHSS 16 (IQR 6). Mean time from symptom onset to groin puncture was 289 ±195 min. According to interventionalist preferences 86.2% (n=56) were treated with stentrievers (n=7 in combination with intra-arterial tissue plasminogen activator (tPA), 4.6% (n=3) received intra-arterial tPA only, and 9.2% (n=6) diagnostic angiography only. Good recanalization (78.5%) was associated with dramatic improvement (48% vs 14.8%; p=0.02), smaller infarct volumes (8 vs 82 cc; p=0.01) and better outcome (mRS 0-2: 66.3% vs 30%; p=0.03). SICH (9%) was not associated with treatment modality or device used. After adjusting for age and preprocedure NIHSS, good recanalization emerged as an independent predictor of dramatic improvement (OR=5.9 (95% CI 1.2 to 29.2), p=0.03). Independent predictors of good outcome at 3 months were age ( OR=1.067 (95% CI 1.005 to 1132), p=0.03) and baseline NIHSS ( OR=1.162 (95% CI 1.041 to 1.297), p<0.01). Conclusions: Endovascular treatment of M2 MCA occlusion with stentrievers seems safe. Induced recanalization may double the chances of achieving a favorable outcome, especially for patients with moderate or severe deficit.