BACKGROUND: Mechanical thrombectomy (MT) has become the standard treatment for acute ischemic stroke caused by large vessel occlusion (LVO). Despite successful recanalization, approximately one-half of the patients do not achieve a favorable outcome, which is known as "futile recanalization" (FR). The present study aimed to explore the association between stress hyperglycemia and FR after MT. METHODS: Data from 224 eligible patients with LVO, who underwent MT at the authors' hospital between January 2015 and December 2023, were retrospectively reviewed. Patients were divided into FR and non-FR groups according to functional independence at 3 months according to a modified Rankin scale. Factors influencing FR were identified using multivariate regression and a receiver operating characteristic (ROC) curve analysis. RESULTS: FR was observed in 40 (38.4%) of 104 patients who fulfilled the inclusion criteria. Multivariable regression analysis revealed that older age (odds ratio [OR] 1.09
95% confidence interval [CI] 1.03-1.15
P = 0.001), an increased number of passes (OR 1.57 [95% CI 1.03-2.40]
P = 0.034), and a greater stress hyperglycemia ratio (SHR) (OR 16.0 [95% CI 1.49-172.8]
P = 0.021) were independently associated with FR after MT. ROC curve analysis revealed that a model of combining age, SHR, Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores, procedure duration, systolic blood pressure, and number of passes (area under the ROC curve: 0.83, [P <
0.01]) were accurate. CONCLUSIONS: Results of this study revealed that older age, an increased number of passes, and greater SHR were independently associated with FR after MT in patients with acute ischemic stroke caused by LVO.