Abstract 4: Endovascular Thrombectomy May Be Safe and Effective in Patients With Large Core Lesions on Either Simple CT or Perfusion Images

Abstract

Background: Endovascular thrombectomy (EVT) efficacy and safety is not established in patients with large core. We evaluated the clinical and radiologic outcomes following EVT in acute strokes with large ischemic core lesions defined by CT ASPECTS and/or CTP. Methods: From a multicenter prospective cohort study of imaging selection for thrombectomy (SELECT), patients with large ischemic core on CTP (rCBF< 30%) >50 ml and/or ASPECT≤5 up to 24 hrs from last known well were identified at 9 U.S centers. All patients received a baseline CT and CTP with automated ischemic core determination by RAPID. A blinded core lab adjudicated all images. The primary outcome was 90 day mRS 0-2. Safety outcomes were sICH and mortality. Outcomes of EVT patients were compared to those who received medical management (MM) only. Results: Of 445 enrolled, 106 had large core on either CT or CTP: 71 ASPECTS≤5 (EVT 37, MM 34) and 75 CTP core >50 ml (EVT 40, MM 35), 40 on both CT and CTP. Median (IQR) age 66 yr, NIHSS 20 (16-23), time to puncture 224 min (range 69-832), ASPECTS 5 (4-6) and CTP core 72 ml (41-96). Baseline characteristics were similar in EVT vs. MM patients in both CT and CTP definition groups. The EVT group had better mRS 0-2 rates as compared to MM (32 % vs 14%), aOR: 2.9 (95% CI: 1.0-7.9, p=0.041) and a favorable mRS shift on ordinal analysis aOR: 2.0 (95% CI 1.0-4.1, p=0.049), smaller final infarct volume 96 (49-196) vs 175 (127-225) ml, p=0.02, and less infarct growth 44 (0.7-107.6) vs 83 (61-133) ml, p=0.03 with similar mortality 29% EVT, 42% MM, p=0.16 and sICH 13% EVT, 7% MM, p=0.3. EVT patients were more likely to achieve mRS 0-2 if treated early (0-6) vs late (>6-24 hrs) for both CTP defined (27% vs 0%) and CT defined large core (44% vs. 18%). The good outcome declined by 20% for each hr of treatment delay (Fig 1). Conclusion: EVT may be effective and safe for patients with a large core, especially if treated early. RCTs are needed.