ABSTRACT NUMBER: ESOC2026A2451 REOCCLUSION FOLLOWING SUCCESSFUL ENDOVASCULAR RECANALIZATION IN ANTERIOR CIRCULATION STROKE

Abstract Background and aims Reocclusion may negate the benefits of endovascular treatment (EVT). We assessed the incidence and clinical impact of reocclusion in patients with anterior circulation large vessel stroke randomized to intravenous thrombolysis (IVT) + EVT versus direct EVT. Methods We included patients from the MR CLEAN NO IV trial with successful recanalization on the final angiographic run. Reocclusion was assessed on 24-hour CTA or MRA. Patients with unsuccessful recanalization or unavailable or poor-quality follow-up imaging were excluded.Our primary outcome was functional outcome (90-day ordinal modified Rankin Scale (mRS)). Additionally, we assessed whether reocclusion rates were associated with baseline characteristics, including intracranial atherosclerotic stenosis (ICAS) and collaterals score, and with randomization to IVT+EVT versus direct EVT. Results Of 539 participants, 410 were included. Reocclusion occurred in 15 patients (3.7%). Reocclusion was associated with worse functional outcome (median mRS 5 [IQR 2–6] vs 2 [IQR 2–4]; cOR 0.23, 95%CI 0.09–0.59; p=0.002, Figure 1). IVT+EVT was not significantly associated with reocclusion (direct EVT: 9/210 [4.3%] vs IVT+EVT: 6/200 [3.0%]; OR 1.46, 95%CI 0.52–4.43; p=0.48). Patients with reocclusion more frequently had ICAS on angiography (36% vs 1.9%; p<0.001). Conclusions Reocclusion occurred in approximately 4% of patients after EVT and was associated with worse functional outcome. We did not find evidenve of a protective effect of IVT+EVT against reocclusion, though event rates were low and it is not possible to exclude a meanigful effect. ICAS was associated with reocclusion. Conflict of interest Dr Majoie reports grants from European Commission to other; grants from Health Evaluation Netherlands to other; grants from Stryker Corporation to other; stock holdings in Nicolab; grants from Dutch Heart Foundation to other; and grants from Boehringer Ingelheim to other. Dr Roos reports stock holdings in Nicolab. The other authors report no conflicts. All other authors have nothing to disclose. Figure 1 - belongs to Results