Abstract 111: Endovascular Thrombectomy May Be Safe and Effective in Patients With Large Core and Early Presentation

Abstract

Background: Large infarct cores on CT or CTP were an exclusion from most trials of Endovascular thrombectomy (EVT). However, large cores may be seen in occasional patients presenting within the early window (0-3 hours) and may not preclude potential benefit from thrombectomy. We studied clinical outcomes with thrombectomy in patients presenting with large cores measured by CT or CTP within 3 hours of last known well (LKW). Methods: From a multicenter prospective cohort study of imaging selection for EVT (SELECT), patients with a large ischemic core (CBF<30%) > 50cc or ASPECT≤5 presenting within 3 hours from LKW to imaging were identified. All patients received CT and CTP with mismatch determination by RAPID software. A blinded independent core-lab adjudicated all images. Good (90 day mRS 0-2) and safety (sICH and mortality) outcomes were compared between patients who received EVT and those with medical management (MM) only. Results: Of 445 patients enrolled, 54 met criteria for large core and early presentation; 28 had ASPECT≤5 (17 EVT, 11 MM) and 40 had CTP >50 cc (26 EVT, 14 MM) and 14 on both CT and CTP. Median (IQR) age 66 years (60, 75), NIHSS 20 (18, 23), LKW to puncture 162 min (range 69-343). Baseline characteristics were similar between EVT and MM. Patients with large core whether on CT (ASPECT≤5) or CTP (CBF>50cc) had more frequent good outcome with EVT (30% overall, CT 35%, and CTP 27% vs 0% MM, p=0.04, Fig 1) Furthermore, EVT resulted in smaller average final infarcts (77 vs 202 ml, p=0.03), similar mortality (31% vs 29%, p=0.87) and sICH (16% vs 6%,p=0.34). In patients who achieved good outcome with thrombectomy, EVT resulted in smaller infarct growth 31 ml (10-58) vs 111 cc (67-233) in patients who had poor outcome, p=0.01. Outcome rates were similar if large core was defined as >70ml. Conclusion: Patients with large core infarct measured by CT or CTP presenting within 3 hours may benefit from EVT. Time may trump imaging in patients with large core who present early.