Hospital transfer associated with increased mortality after endovascular revascularization for acute ischemic stroke

Background Patients with an acute ischemic stroke (AIS) due to large vessel occlusion often require transfer to an endovascular center for treatment. Objective To assess the effect of hospital transfer on outcomes after endovascular revascularization. Methods Outcomes of endovascular revascularization were compared between directly admitted and transferred patients using data from a national database and our own institution. Results 118 institutions within the database reported outcomes of 8533 inpatient admissions for endovascular treatment of AIS. Mortality rate (14.9% vs 18.6%; p=0.049) and mortality index (1.1 vs 1.6; p=0.048) were significantly lower among directly admitted patients than among transferred patients. Within our institutional cohort of 140 patients who underwent endovascular therapy, directly admitted patients had a significantly faster time to revascularization than transferred patients (277.4 vs 420.4min; p≤0.0001). Among transferred patients, an increasing distance of transferred hospital to our home institution was associated with an increasing risk of mortality (unit OR=1.26, 95% CI 1.07 to 1.54; p=0.0061). Conclusions Outcomes of revascularization may improve with methods to identify patients with large vessel occlusion before hospital admission, thus increasing the likelihood of initial triage to a comprehensive stroke center for patients eligible for endovascular intervention.