ABSTRACT NUMBER: ESOC2026A1099 MECHANICAL THROMBECTOMY VERSUS BEST MEDICAL TREATMENT FOR ISOLATED POSTERIOR CEREBRAL ARTERY OCCLUSION: RESULTS FROM A MULTICENTER REGISTRY IN SPAIN

Abstract Background and aims Evidence for mechanical thrombectomy (MT) in isolated posterior cerebral artery occlusion (iPCAO) is limited. We compared MT versus best medical treatment (BMT) in a Spanish multicenter cohort. Methods Retrospective multicenter registry of adults with iPCAO between 2019-2025. Data on demographics, vascular risk factors, and clinical and radiological characteristics were collected. Primary outcome was good functional outcome (defined as modified Rankin Scale [mRS] 0–2) at 90-days. Secondary outcomes were excellent outcome (mRS 0–1) and early neurological improvement at discharge (NIHSS decrease ≥4). Safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Treatment effects were estimated with propensity-score inverse probability of treatment weighting (IPTW). Results 656 patients were included from 17 stroke centers in Spain; 214 (32.6%) underwent MT. Intravenous thrombolysis use was similar in both groups (~28%). MT patients had higher baseline NIHSS (median 8 vs 4) and more P1 occlusions (58.8% vs 29.1%). Successful reperfusion (mTICI 2b–3) was achieved in 79.4% of MT cases. See table for main results. Conclusions MT is associated with early neurological recovery but showed no 90-day functional benefit after adjustment and was associated with more sICH. These results support the need for better patient selection and randomized-designed studies in iPCAO. Conflict of interest Name of author: nothing to disclose Table 1 - belongs to Results