Abstract Number: Esoc2026a2406 Increased Vascular Tortuosity in Individuals With Frailty and Its Effect on Poorer Outcomes After Mechanical Thrombectomy

Abstract Background and aims Frailty – the loss of physiological reserve reflecting biological age – is associated with an attenuated neurological recovery and increased mortality after mechanical thrombectomy. However, the mechanisms underlying this relationship remain poorly understood. This study investigated the relationship between frailty, vascular tortuosity, and the impact on outcomes after thrombectomy. Methods We performed a retrospective study of thrombectomy cases at a UK comprehensive stroke center between January 2023-December 2024. Individuals with anterior circulation strokes underwent vascular geometry analysis to calculate the tortuosity index (TI) of the extracranial internal carotid artery. Frailty was measured using a standardised frailty index. Comorbid conditions, procedure details, and outcomes were collected retrospectively. Multivariable regression was preformed to identify associations between patient characteristics and TI. Results 316 internal carotid arteries were analysed from 180 patients. Mean age was 72 (+/-12.2) years and 88 (43.9%) were women. Median TI was 11.73 IQR 5.83-22.26. On univariable analysis, frailty was associated with increased vascular tortuosity (rho=0.26, p0.01). On multivariable analysis, increased vascular tortuosity was independently associated with frailty index (beta=3.61, p=0.048) and diastolic blood pressure (beta=0.69, p=0.02), but not with age, sex, and vascular comorbidities. TI values for ipsilateral carotids demonstrate a significant correlation with procedure duration (rho=0.21,p=0.01) and 90-day modified Rankin score (rho=0.33,p=0.02). Conclusions Frailty is independently associated with Increased vessel tortuosity, which is associated with longer procedure times and poorer outcomes. This highlights the importance of biological – rather than chronological – age in stroke, and identifies a possible mechanism by which frailty affects thrombectomy outcomes. Conflict of interest LB: Nothing to disclose. NE: Grant support from the Stroke Association.