Abstract WP28: Yield of ASPECTS and CTA-Based Selection Criteria for Mechanical Thrombectomy in Patients Treated Within 6-24 Hours From Symptom Onset

Abstract

Background: Recent extended window (EW) trials support the benefit of mechanical thrombectomy (MT) in anterior circulation emergent large vessel occlusions (ELVO). However, only up to 1.7% of consecutive acute ischemic strokes (AIS) were eligible for EW-MT using clinical trial selection criteria. We examined eligibility and outcomes of EW-MT in consecutive ELVOs using pragmatic selection criteria. Methods: We prospectively evaluated consecutive patients presenting between 6-24 hours that underwent MT using selection criteria consisting of only non-contrast CT (ASPECTS > 6), CTA occlusion + good collateral scores (JNIS 2016;8:559-562). Effectiveness outcomes included TICI 2b-3 and 3-month modified Rankin Scores (mRS); safety outcomes included in-hospital mortality and symptomatic intracerebral hemorrhage (sICH). Results: 767 consecutive AIS patients presented within 6-24 hour window, and of these 48 (6%) anterior circulation ELVOs underwent MT (mean age 63±17 years; 56% men; median NIHSS 16 [IQR 10-19]; median groin puncture to recanalization 53 minutes [IQR 41-85]). Median ASPECTS was 9 (IQR 8-10), and 79% (n=38) of patients had good CTA collateral grade. Occlusions were primarily M1 MCA (46%), with 29% tandem occlusions. Successful recanalization (mTICI 2b or 3) was achieved in 73% (n=35), while 6% (n=3) of patients developed sICH. In-hospital mortality was 25% (n=12), however 40% (n=19) achieved 3-month mRS 0-2. Conclusions: The use of standard of care CT/CTA yields an acceptable rate of MT eligibility, allowing a group of patients facing likely death or severe disability to obtain reasonable safety and effectiveness outcomes.