Abstract 127: Intra-Arterial Therapy in Stroke Patients Transferred from Referral Centers

Abstract

Background: The effectiveness of intra-arterial therapy (IAT) for patients presenting to endovascular capable centers with acute ischemic stroke (AIS) and large artery occlusion (LAO) has not been proven. Most AIS patients present to hospitals which do not have IAT capability and many are transferred to tertiary centers for IAT. We addressed if IAT improves outcome of patients transferred from outside facilities. Methods: In a multicenter retrospective study, we identified 615 AIS patients with LAO transferred to centers that offered IAT within 12 hours from ictus during 01/05-03/14. Patients were divided into two groups (IAT vs No IAT) (Figure 1). Logistic regression was performed for good and poor (discharge mRS 0-2 and 4-6, respectively) outcome. Univariate and multivariate analyses evaluated independent predictors of good and poor outcome after IAT. Results: Patients in the IAT group had more severe strokes, arrived faster to tertiary centers, had less ischemic changes on CT and better collateral flow compared to the non-IAT group (Table 1). Fewer IAT patients had ASPECTS deterioration during transfer. IAT patients had 4 times the odds for good outcome (OR 3.7, 95%CI 2.2-6.3, p<0.0001) compared to those without IAT, even after adjusting for stroke severity, ASPECTS, ASPECTS decay, collateral flow, time, and tPA (OR 2.51 95%CI 1.2-5.8, p=0.02). mRS distribution demonstrated a shift towards better outcomes in IAT treated patients (Fig 2). Patients with better outcome had better ASPECTS/collaterals, were younger and had lower NIHSS. Time to IAT was not an independent predictor of outcome. Conclusion: IAT may improve outcome in selected transfer patients with LAO, a group that was under-represented in prior trials. In late-treated patients, collateral flow, the extent of infarct, and age may be more important than time in determining outcome from IAT. Identifying patients at referral hospitals who may benefit from IAT and expediting their transfer should be tested in RCTs.