Abstract WP59: Endovascular Therapy for Distal Middle Cerebral Artery Occlusion: Sub-analyses of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan Registry 2 (RESCUE-Japan Registry 2)

Abstract

Objective: The efficacy of endovascular therapy (EVT) for distal middle cerebral artery (MCA) occlusion remain debatable. We compared the EVT with conservative therapy (no EVT) in real-world patients with distal MCA occlusion. Methods: We analyzed the data from the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan Registry 2, which enrolled the consecutive patients with acute ischemic stroke due to large vessel occlusions. We selected patients with isolated M2 or M3 occlusion, and those with functional independence (modified Rankin Scale [mRS] score =<1) before the onset. We divided patients into EVT and no EVT groups. The primary outcome was a favorable outcome (mRS 0-2 at 90 days). Multivariable logistic regression model was developed to compare both groups. We conducted the subgroup analyses for age, gender, ASPECTS score, NIH Stroke Scale (NIHSS) time from onset to arrival, use of t-PA, location of occlusions (M2 vs M3). Results: A total of 427 patients [372 (87%) were M2 occlusion] were analyzed from 2420 patients originally enrolled in the registry. There were 190 patients in EVT and 237 in no EVT groups. The EVT group showed a higher baseline NIHSS score (median interquartile range [IQR], 15 [9-19] versus 8 [4-15]). The primary outcome occurred in 55.7% and 54.4% of the EVT and no EVT groups, respectively. There were no significant differences for a favorable outcome as a whole and the adjusted odds ratio (aOR) was 1.52 [95%CI, 0.97-2.42; p=0.06]. Subgroup analyses showed a favorable outcome for EVT group in the subgroup of M2 occlusion with aOR of 1.84 (95%CI, 1.13-3.00) and of NIHSS≥6 with aOR of 2.14 (95%CI, 1.29-3.55). Conclusions: In patients with distal MCA occlusion, EVT seems effective for patients with M2 segment occlusion or NIHSS≥6.