Abstract DP229: Real-World Effectiveness of CTP-Based Endovascular therapy (EVT) in Elderly: Outcomes between Large Vessel and Medium Vessel Occlusions

Introduction: There is limited data regarding optimizing selection of elderly patients (age ≥80 years) with CT Perfusion (CTP) for endovascular thrombectomy (EVT). We aimed to evaluate outcomes in elderly patients selected for EVT with CTP compared to younger patients. Methods: A retrospective study from a large academic medical center. Patients with occlusion and treated with EVT between December 2017 and December 2024 were included in this study. Patients were excluded if: CTP completed after EVT, CTP failed or missing baseline or 90-day modified Rankin Scale scores (mRS). We compared nonagenarians (≥90 years old), octogenarians (80-89 years old) and younger patients (<80 years old). Propensity scores using inverse probability of treatment weighting were used to adjust baseline covariates between the age groups. Primary outcome was good 90-day functional outcome (mRS ≤2 or at baseline). Secondary outcomes included excellent reperfusion (TICI ≥2C) and symptomatic intracranial hemorrhage (sICH) post-EVT. Outcomes for medium vessel occlusions (MeVO) were studied in a subgroup of elderly patients (≥80 years old). Outcomes were evaluated using binomial logistic regression models. Results: There were 720 patients selected for EVT using CTP and after exclusions, 689 patients were included. Mean age±SD was 74.10±14.04 years [424(61.5%) <80 years old; 158(22.9%) 80-89 years old; 107(15.5%) ≥90 years old] with initial NIHSS of 14 (IQR, 7 – 19) and 389 (55.6%) were female. Older patients were less likely to achieve a good 90-day outcome compared to younger patients: octogenarians adjusted Odds Ratio (aOR) = 0.49 [95%CI 0.32 – 0.75], P=0.001; nonagenarians aOR = 0.38 [95%CI 0.20 – 0.70], P=0.002. sICH was more likely in nonagenarians, aOR = 2.19 [95%CI 1.11 – 4.35], P=0.03, but not octogenarians, P=0.63. There was no difference in excellent reperfusion across the age groups, all P>0.05. Elderly patients with fast progressing core volumes had worse 90-day outcomes compared to elderly patients with slow progressing cores, aOR = 0.39[95%CI 0.27 – 0.57], P<0.001. Elderly patients with MeVO were less likely to achieve a good functional outcome at 90 days compared to younger patients, all P<0.05. Conclusions: Elderly patients, especially nonagenarians, were less likely to achieve good functional outcomes after EVT. Ischemic core growth was associated with outcomes in elderly patients and may be a variable to consider for better outcomes in these patients.