Mechanical thrombectomy in nonagenarians: real-world outcomes from a highly selected cohort treated at a comprehensive stroke center

Abstract

Abstract Background Evidence supporting mechanical thrombectomy (MT) in very elderly patients remains limited, as nonagenarians are underrepresented in randomized trials and frequently excluded from MT in routine practice. We evaluated the effectiveness and safety of MT in carefully selected patients aged ≥ 90 years treated at a comprehensive stroke center. Methods We conducted a retrospective single-center cohort study including consecutive patients with anterior circulation large vessel occlusion treated with MT. Fifty nonagenarians treated between 2017 and 2025 were compared with 100 younger patients treated in 2023. In both groups, only patients with preserved pre-stroke functional independence (modified Rankin Scale [mRS] 0–2) were included. Nonagenarians underwent detailed pre-treatment clinical assessment prior to treatment. Primary outcomes were functional independence (mRS 0–2) and all-cause mortality at 90 days. Secondary outcomes included successful reperfusion (mTICI 2b–3), neurological status at discharge, and hemorrhagic complications. Multivariable regression models were used to adjust for baseline imbalances and clinically relevant prognostic factors. Results Nonagenarians had a substantially higher burden of comorbidities and worse pre-stroke functional status than younger patients. Successful reperfusion rates were similar between groups (92% vs. 90%). Functional independence at 90 days was achieved in 18% of nonagenarians and 50% of younger patients, while 90-day mortality was 52% and 20%, respectively. In unadjusted analyses, nonagenarians had lower odds of functional independence and higher odds of mortality. After adjustment for baseline clinical and prognostic factors, the estimated associations were attenuated, although confidence intervals remained wide and the study could not exclude a clinically relevant age-associated effect. Parenchymal hematoma occurred more frequently among nonagenarians, whereas rates of symptomatic intracerebral hemorrhage were comparable between groups. Conclusions In this highly selected real-world cohort, MT achieved high rates of successful reperfusion in nonagenarians, but functional outcomes and mortality were substantially less favorable than in younger patients. Adjustment for baseline clinical and prognostic factors attenuated the estimated associations, although clinically relevant age-associated differences could not be excluded. These findings support cautious, individualized treatment decisions incorporating chronological age, pre-stroke function, comorbidity burden, imaging findings, and the overall clinical profile.