Association of Time Course of Thrombectomy and Outcomes for Large Acute Ischemic Region: RESCUE-Japan LIMIT Sub-Analysis

Background: The effectiveness of endovascular thrombectomy (EVT) has been proven even in patients with large cerebral infarction in early time window. However, the association of the time course with the treatment effect is unknown. The aim of this analysis was to evaluate the influence of the time course from stroke onset to reperfusion on the therapeutic effect of EVT.Methods: The subjects were patients with occlusion of large vessels and sizable strokes on imaging (ASPECTS 3 to 5) in RESCUE-Japan LIMIT (a multicenter, randomized clinical open-label trial of EVT vs. medical care alone). In the current analysis, the clinical and time course characteristics associated with a favorable outcome (modified Rankin Scale (mRS) 0-2 and 0-3 at 90 days) were examined in patients treated with EVT. Results: The analysis included 71 patients (median age, 77 years; median NIHSS score on admission, 21). Occlusion sites were the internal carotid artery (48%), M1 segment of the middle cerebral artery (72%) and tandem lesions (20%). Of these patients, 23 (32%) had mRS 0-3 and 12 (17%) had mRS 0-2 at 90 days. In multivariate analysis, there were independent associations of onset to reperfusion time (OR, 0.991; 95% CI, 0.984-0.999, P = 0.01) and puncture to reperfusion time (OR, 0.952; 95% CI, 0.917-0.988, P < 0.001) with mRS 0-3 at 90 days, and of puncture to reperfusion time (OR, 0.930; 95% CI, 0.872-0.991, P = 0.004) with mRS 0-2 at 90 days. Conclusions: Earlier reperfusion was related to a favorable outcome in patients with acute large vessel occlusion with a large ischemic region. Onset to reperfusion time and especially puncture to reperfusion time were independently associated with a favorable outcome. These results suggest the importance of timing and uninterrupted EVT in this patient population.