Determinants of Futile Recanalization and the Influence of Age After Endovascular Therapy for Acute Ischemic Stroke: A Retrospective Single-Center Cohort Study

Background and Objectives: Functional independence is not always achieved after successful recanalization with endovascular therapy (EVT) for acute ischemic stroke, a phenomenon termed futile recanalization (FR). We investigated factors independently associated with FR and explored whether these associations differed by age. Materials and Methods: In this retrospective single-center study, 231 consecutive patients treated with EVT between January 2021 and December 2024 were analyzed. FR was defined as a modified Rankin Scale score > 2 at 90 days despite a modified Thrombolysis in Cerebral Infarction (mTICI) grade of 2b–3. Model 1 included all patients with successful recanalization. Model 2 was restricted to patients with anterior circulation infarction and assessable imaging and additionally included the Alberta Stroke Program Early CT Score (ASPECTS) and collateral status. Age interactions were tested. Results: Recanalization was successful in 191 patients (82.7%), of whom 114 (59.7%) had FR. In Model 1 (n = 191), admission National Institutes of Health Stroke Scale (NIHSS) score (odds ratio [OR], 1.29 per point; 95% confidence interval [CI], 1.18–1.42), admission glucose (OR, 1.01; 1.00–1.02), and puncture-to-recanalization time (OR, 1.02; 1.00–1.03) were independently associated with FR. In Model 2 (n = 146), sufficient collateral status (OR, 0.19; 0.08–0.47), ASPECTS (OR, 0.60; 0.39–0.91), NIHSS score, neutrophil-to-lymphocyte ratio (NLR), dyslipidemia, and procedural duration were independently associated with FR, whereas glucose was not retained; Model 2 had an area under the curve of 0.88. Age ≥ 80 years was not independently associated with FR; the only significant interaction was with glucose in Model 1. Conclusions: Stroke severity and procedural duration were independently associated with FR in both models. Imaging variables contributed to prognostic assessment in anterior circulation infarction. Age ≥ 80 years was not independently associated with FR. The NLR association and age-stratified findings remain exploratory.