Abstract TP306: Unexpected language recovery pattern after proximal left middle cerebral artery (MCA) versus distal left M1 arterial segment thrombectomy

Background: The impact of arterial segment location on post-thrombectomy language improvement has not been well characterized. We evaluated trends in language function after thrombectomy and hypothesized that patients with proximal left MCA occlusions would show greater language improvement when compared to distal M1 occlusions post thrombectomy. Methods: A retrospective analysis of 160 patients who underwent thrombectomy of proximal left MCA vs. distal M1 occlusions was conducted. Baseline demographics, stroke severity, and language function were extracted. Language outcomes were assessed using NIHSS language sub-score (Question 9) before thrombectomy and 24-hour post. Multiple logistic regression was utilized to compare outcomes between proximal MCA trunk and distal M1 groups, adjusting for age, baseline NIHSS and language score. Patients with baseline aphasia (Item-9 > 0) and a defined endpoint of ≥1 point improvement in Item-9 at 24-hour post-thrombectomy were analyzed. We conducted a multivariable logistic regression, adjusting for age, sex, baseline Item-9 severity, thrombolytic use, and reperfusion success. Results: 160 patients with baseline aphasia were included (53.12% female, mean age [71.09 ± 13.78]) in the study. In this cohort, the left MCA main trunk vs. distal M1 was associated with lower odds of ≥1 point language improvement at 24 h (adjusted OR 0.48, 95% CI 0.24–0.95, p= 0.0362). Female sex showed higher odds of improvement (OR 2.05, 1.01–4.26, p= 0.0469). Greater baseline Item-9 severity trended toward lower odds (OR 0.67, 0.42–1.05). Thrombolytic use was not associated with improvement (OR 1.05, 0.48–2.40). Model discrimination: AUC 0.65 (95% CI 0.56–0.74). Conclusion: After thrombectomy, patients with distal left M1 demonstrated significantly greater early (24-hour) language improvement compared to patient with proximal left MCA occlusions following thrombectomy independent of age, baseline language severity, thrombolytic use, and reperfusion success. These findings support thrombus location as a practical predictor for early language recovery and may assist bedside prognostication after thrombectomy.