Abstract TMP9: Procedural and Functional Outcomes of ADAPT Thrombectomy for Stroke Involving Anatomical Divisions of the M2 Segment

Abstract

Introduction: Endovascular thrombectomy (ET) is the current standard of care for acute ischemic stroke (AIS) for large vessel occlusion. Recently, there has been interest and an effort to extend thrombectomy to patients with M2 occlusions. Here, we evaluate the difference in presentation, and procedural and clinical outcomes of patients undergoing ADAPT thrombectomy between superior or inferior divisions of M2 and M1. Methods: We retrospectively reviewed a database of patients undergoing ADAPT for AIS between 06/2013 and 04/2018. Patients with M1 or M2 segment AIS were included. M2 occlusions were classified to superior and inferior divisions. Procedural outcomes were obtained from procedural notes, and functional outcomes were collected at the 90-day visit to neurologist. Results: A total of 205 patients with M1, 65 with M2 superior division (M2S), and 57 patients with inferior division (M2I) AIS were included. As shown in Table 1, M1 and M2S patients had comparable NIHSS at presentation and were both significantly higher than M2I group (p< 0.01). M2 occlusions had significantly longer procedure times and higher number of aspiration attempts (p<0.05). M2S occlusions had significantly lower recanalization rates and higher rates of stent retriever use. The rates of good outcome (mRS 0-2) were 46% in M1, 34% in M2S, and 44% in M2I patients. On multivariate analysis controlling for presenting deficits and ASPECTs, an M2S occlusion was associated with longer procedure times (p<0.01), lower odds of good outcomes (OR=0.4, p<0.05), and lower odds of TICI 2C/3 recanalization (OR=0.36, p<0.05) compared to M1 occlusions. No difference in post-procedural hemorrhage was observed. Conclusions: ADAPT is safe and effective in M2 occlusions, but the procedural success and efficacy of ADAPT in M2 stroke is influenced by the anatomic division.