Abstract 79: Direct Bypass To Endovascular Capable Stroke Center Compared To Secondary Transfer From Primary Stroke Centers

Introduction: All stroke care in our metropolitan region is provided by three primary stroke centers (PSCs) and a central endovascular thrombectomy capable stroke center (EVT-SC). There is a hybrid organizational structure with all potential large vessel occlusion (LVO) patients taken to the nearest stroke center during office-hours, and directly bypassed to the EVT-SC after-hours. Aim: To compare process times and EVT outcomes in PSC locality patients who were transferred to the EVT-SC by these two methods. Methods: Between August 2017 and February 2021, consecutive anterior LVO patients transferred via road with EVT initiation within 6 hours were included. Patients were grouped into method of presentation: 1) PSC locality patients directly bypassed to EVT-SC (‘EVT-SC direct’); 2) PSC locality patients taken to local PSC with subsequent transfer to EVT-SC (‘PSC-transfer’); 3) patients normally resident in the EVT-SC locality (‘EVT-SC local’). The primary outcome was 3-month functional independence (modified Rankin Scale score 0-2). Secondary outcomes included symptomatic intracranial hemorrhage, and mortality at 7-days and at 3-months. Results: 343 patients (142 women; mean±SD age 66.5±16.0 years) were included. There were 91 (26.5%) EVT-SC direct, 168 (49.0%) PSC-transfer, and 84 (24.5%) EVT-SC local patients. For EVT-SC direct patients, the median (interquartile range) distance travelled was 13 (10-18) miles. EVT-SC direct patients were younger (mean±SD age 63.8±15.1 years versus 68.5±15.0 years; P =0.02), had shorter LKN-to-thrombolysis (120 vs 147 minutes, P =0.004) and LKN-to-puncture times (190 vs 230 minutes, P< 0.001), compared to the PSC-transfer patients. With multivariable logistic regression analysis, at 3-months EVT-SC direct patients were more likely to be functionally independent (OR=2.04, [95% CI, 1.12-3.73]; P =0.02), and less likely to be dead (OR=0.33, [95% CI, 0.12-0.91]; P =0.03). For every 100 patients directly bypassed to EVT-SC, there were 14 additional patients functionally independent and 9 less deaths at 3-months. Conclusion: The results of this study suggest where the distance is less than 20 miles, direct bypass to EVT-SC is associated with better process times and outcomes.