Abstract 332: Multi‐Center Comparison of Safety and Efficacy of Intravenous Thrombolytics in Patients Undergoing Endovascular Therapy: Regression Discontinuity Analysis

Introduction Many clinical practices have switched from alteplase (tPA) to tenecteplase (TNK) given recent clinical trial results. The safety and efficacy of TNK in endovascular treated cohorts, compared to tPA and no thrombolytic remain incompletely characterized. Methods From our prospectively collected multi‐center institutional registry, we identified patients treated with endovascular therapy with and without thrombolysis. All 4 hospitals in the cohort switched from tPA to TNK on a single day (March 7 2023), and patients were included if they were treated within 300 days before or after this date. The primary outcome was likelihood of functional independence (mRS 0‐2) at 90 days. Secondary endpoints included rates of intracranial hemorrhage and substantial reperfusion (TICI 2c‐3). Analysis was performed using sharp regression discontinuity, taking advantage of the fact that switch from tPA to TNK occurred at a specific time, such that other measured and unmeasured confounders should be matched. Results Among 161 patients that met inclusion criteria, median age was 69 [IQR 57 ‐ 78], median NIHSS 17 [IQR 11 ‐ 22] and 50% were female. 100 (62%) of patients did not receive thrombolysis, 37 (23%) tPA and 24 (15%) TNK. In univariable analysis, rates of substantial reperfusion were comparable (71% vs. 73% vs. 71%, no thrombolysis vs. tPA vs. TNK, p=0.9), as were rates of hemorrhagic transformation (38% vs. 30% vs. 29%, no thrombolysis vs. tPA vs. TNK, p=0.85). Rates of functional independence were similar (27% vs. 43% vs. 33%, no treatment vs. tPA vs. TNK, p=0.19). In regression discontinuity analysis, restricted to only the patients who were treated with tPA or TNK, there were no differences in likelihood of functional independence (coef = ‐0.96, p=0.83). Conclusion In this multi‐center cohort of patients treated with EVT, we did not identify any differences in rates of reperfusion, hemorrhage or functional independence after switching from tPA to TNK.