Association of Reperfusion and Procedural Characteristics with Endovascular Thrombectomy Outcomes in Large Core Stroke: Sub‐Analysis from the SELECT2 Trial

Endovascular thrombectomy (EVT) was shown to be safe and efficacious in patients with large core stroke in multiple randomized controlled trials. However, the impact of reperfusion and other procedural metrics on EVT outcomes in this population has not been well‐characterized. Methods From the SELECT2 trial, we evaluated the association between reperfusion status, first‐pass effect (near‐complete or complete reperfusion [extended thrombolysis in cerebral infarction (eTICI) 2c‐3] in 1 pass), procedure time and primary technique (aspiration vs stent‐retriever) with functional outcomes in patients receiving EVT across ASPECTS (3 vs 4 vs 5) and core estimate strata (<70 vs ≥70ml, <100 vs ≥100ml, and <150 vs ≥150ml). Results Of 180 patients who received thrombectomy, 144 (80%) achieved successful reperfusion (eTICI 2b‐3) and demonstrated better clinical outcomes (adjusted generalized odds ratios [aGenOR]: 1.48, 95% confidence interval [CI]: 1.01–2.15), compared with unsuccessful reperfusion. Results were consistent across ASPECTS and core estimate strata. Additionally, complete or near‐complete reperfusion (eTICI 2c‐3) was associated with better functional outcome (aGenOR: 1.99, 95% CI: 1.33–2.97) in patients achieving successful reperfusion. Functional outcome point estimates favored those with first‐pass‐effect (42 of 167 (25%), aGenOR: 1.46, 95% CI: 0.96–2.24). Longer procedure time was associated with worse modified Rankin scale (mRS) distribution (aGenOR: 0.92, 95% CI: 0.87–0.96, p ‐value = 0.001 for 10 minutes increment). Aspiration‐first technique was used in 43 of 154 (25%) patients and was not associated with higher reperfusion (88% vs 78%, p = 0.18) or better functional outcome (aGenOR: 0.74, 95% CI: 0.50–1.10) as compared with stent‐retriever first. Interpretation Successful reperfusion resulted in improved clinical outcomes in large core patients across baseline ischemic core strata. Near complete or complete reperfusion was further associated with better outcomes, whereas prolonged procedures were associated with worse outcomes. Results were consistent regardless of the technique used. ANN NEUROL 2025;97:175–184