Abstract WMP12: Does IV tPA Improve Outcomes in Stroke Patients with Large Vessel Occlusions Treated with Intra-arterial Therapy?

Abstract

Introduction: The benefit of endovascular therapy (IAT) for the treatment of emergent large vessel occlusion (ELVO) in stroke patients has been established. However, it is not known whether administration of IV tPA prior to IAT is beneficial in these patients. Methods: A retrospective review of ischemic stroke patients in the Providence Health & Services Get with the Guidelines (GWTG) database was performed from 01/2012 to 05/2016. The analysis was limited to patients who presented within 4.5 hours of last known well time (LKWT) and treatment included any form of IAT. End points were limited to data available in the GWTG database, including discharge mRS, discharge NIHSS, change in NIHSS from admission to discharge, and length of stay. Continuous variables were summarized using means and standard deviation while categorical variables were summarized using frequencies and percentages. To yield a more robust estimate against outliers for the time-related variables, medians and interquartile range (IQR) were computed and assessed using Wilcoxon rank sum tests. Chi-square tests and independent two-sample t-tests were used to evaluate the demographic and outcome differences for categorical and continuous variables, respectively. Results: A total of 10,868 patients with an ischemic stroke diagnosis were found in the specified time frame and presented within 4.5 hours of LKWT. Of these, 461 patients were treated with some form of IAT, 235 received IV tPA prior to IAT, 226 had IAT alone due to contraindication to IV tPA. There was no statistical difference in patient demographics, complication rates, TICI score, discharge NIHSS or mRS at discharge. There was a significantly higher NIHSS on admission (18.3 vs 16.7, p = 0.026), greater improvement in NIHSS (11.6 vs. 7.9, p=0.012), longer door to IAT (146 vs 101.5 min, p < 0.0001), and shorter length of stay (5 vs 6 days, p = 0.016) in the IV tPA group. Conclusions: These data suggest that IV tPA, when administered to eligible patients with ELVO, provided some benefit over IAT alone, even though it delayed IAT. Future prospective randomized trials are planned that may better address this question, but these results underscore the need for retrospective analysis of existing data.