Abstract WP1: Thrombectomy Outcomes in Acute Ischemic Stroke due to Middle Cerebral Artery M2 Occlusion with Stent-Retriever, Aspiration, MERCI: Multi-Center Experience

Abstract

Introduction: Recent trials demonstrated that mechanical thrombectomy improve functional outcome in anterior circulation acute ischemic stroke (AIS) due to emergent large vessel occlusion (ELVO) of the middle cerebral artery (MCA) M1 segment. However, such data regarding AIS due to MCA M2 segment ELVO is limited. Analysis of the STAR, SWIFT, and SWIFT-PRIME trials found thrombectomy in MCA M2 occlusion to be feasible in achieving successful reperfusion. The most optimal technique and/or device used for such reperfusion is not clearly defined. We aim to compare the outcome for the contemporary techniques and devices used for thrombectomy of AIS patients due to MCA M2 ELVO. Methods: A retrospective review of AIS patients with MCA M2 ELVO receiving thrombectomy from three tertiary care academic medical centers was conducted. Thrombectomy technique and thrombectomy device utilized were recorded. Outcomes were successful angiographic reperfusion (TICI ≥2b), favorable modified Rankin Scale (mRS≤2) at discharge and at 90 days, and rate of symptomatic intracerebral hemorrhage (sICH). Results: From October 1999 through June 2016, 253 AIS patients underwent thrombectomy for MCA M2 ELVO. Thrombectomy methods utilized were Stent-retriever (n=118), Aspiration only [manual or Penumbra device] (n=83), and MERCI retriever (n=52). Table 1 shows rate of outcomes measured. There was no difference in baseline NIHSS or in stroke onset to groin puncture time. Stent-retriever group showed a significantly higher recanalization rate, lower sICH rate, and favorable 90-day mRS versus Aspiration group or MERCI group, respectively. No significant difference was seen in discharge mRS between the groups. Conclusions: Thrombectomy for AIS patients with MCA M2 ELVO with Stent-retriever appears to be feasible with a significantly higher rate of recanalization, lower sICH rate, and favorable 90-day mRS when compared to Aspiration and MERCI.