Abstract WP2: Tissue Based Selection for Large Vessel Occlusion Thrombectomy Leads to Similar Functional Outcomes in Conventional (0-6 Hours) and Extended (>6 Hours) Window

Abstract

Background: Recent trials have shown benefit of thrombectomy in carefully selected patients in the extended (>6 hours) window. However, it is not clear if the outcomes differ from those undergoing thrombectomy in the conventional (0-6 hours) window. We sought to evaluate if time to treatment modifies the effect of endovascular reperfusion in stroke patients with evidence of salvageable tissue on CT perfusion (CTP). Methods: We retrospectively analyzed data of consecutive patients who underwent thrombectomy in a single center cohort. Demographics, comorbidities, National Institute of Health Stroke Scale (NIHSS), vessel occlusion location, onset to skin puncture time, core infarct volume on initial CTP, recanalization (mTICI IIb/III) rates, final infarct volume and modified rankin scale (mRS) at 90 days were compared between patients who underwent thrombectomy in conventional (0-6 hours) and extended (>6 hour) window. Results: 119 patients were studied of which 55% were female. Univariate analysis showed that the groups (Conventional vs. Extended) were balanced for age (p=0.37), NIHSS (p=0.35), vessel occlusion location (p=0.51), initial core infarct volume (p=0.64) and recanalization (mTICI IIb/III) rates (p=0.55). Final infarct volume (p=0.18) and favorable outcome (mRS 0-2) at 90 days (p=0.65) were similar. Shift analysis did not reveal any significant difference in 90 day outcome (p=0.34). (Figure) After adjustment; age (p=0.004) and final infarct volume (p<0.001) were predictive of favorable outcome. Conclusion: Tissue based selection with CTP for thrombectomy in large vessel occlusion stroke is independent of onset time for favorable functional outcome.