Abstract TP27: Time-window of Endovascular Therapy for Elvo Patients Will be Extended Beyond 24 Hours After Onset ?

Abstract

Background and Purpose: Eendovascular thrombectomy(EVT) had a clinical benefit when it was performed within 6 hours after onset symptom in the emergent large vessel occlusion(ELVO) patients. Recently, it is proved that EVT 6 to 24 hours after stroke onset with mismatch between deficit and infarct is benefit. However, it is not unclear whether EVT is effective more than 24 hours after stroke onset. Method: We enrolled ELVO patients treated with EVT more than 24 hours after stroke onset from our prospective registry. We investigated clinical background including onset to puncture time, clinical stroke type, and recanalization rate. We evaluated patient outcome at 3 months after onset and classified patients into two group; good outcome group as modified Rankin Scale (mRS) 0-2 and poor outcome group as mRS 3-6, respectively. We compared clinical background between two groups. Result: In our stroke registry, 443 patients were treated with EVT from January 2011 to July 2019. Among them, 21 patients(5.4%, age was 69(55-72) years old, and male was 16(76%)) were treated with EVT more than 24 hours after stroke onset. All patients had ELVO and clinical and DWI mismatch, which might be thought to be benefit from EVT. Onset to puncture time was median 2632 (1605-6116) minutes and NIHSS scale was 6(2.5-15), and DWI-ASPECTS were 9(7-10). ICA, M1 and BA occlusion were 8(38%), 4 (19%), and 1(4%) patients, respectively. Symptomatic hemorrhage was none. Regarding to patient outcome at 3 months, good and poor outcome were 14(66.7%) and 7(33.3%) patients, respectively. Among the 19 patients with premorbid mRS 0-2, 14(73%) patients achieved good outcome at 3 months. Age, gender, onset to puncture time, DWI-ASPECTS, and ICA occlusion were not different between good and poor outcome groups. However, good outcome patients less frequently had NIHSS score (3.5(2-7) vs. 15(12-23), P=0.006), and cardioembolic stroke (0% vs. 14%, P=0.333). Conclusion: More than a half of ELVO patients with clinical DWI mismatch more than 24 hours after stroke onset had good outcome from EVT. There is possibility that time window of EVT for ELVO patients is extended beyond 24 hours after stroke onset.