Abstract TMP16: IV tPA Does Not Delay Endovascular Thrombectomy and is Associated With Improved Clinical Outcomes

Background: Whether bridging therapy with IV tPA delays endovascular thrombectomy (EVT) or alters clinical outcomes is unknown. Methods: In this prospective multicenter cohort study of imaging selection for EVT (SELECT), consecutive patients with anterior circulation (ICA, M1, M2) occlusions who presented within 24 hrs from last known well were enrolled at 9 centers. We stratified patients into those who received IV tPA prior to EVT vs those who did not. Results: Of 445 enrolled, 284 received EVT; 222 (78%) treated within 6 hrs and 62 (22%) >6-24 hrs. 65% received IV tPA. Baseline characteristics were similar between the tPA and no tPA groups. There were no workflow delays associated with IV tPA: arrival to groin puncture, median (IQR) 92 (64-117) min in the tPA group vs. 82 (64-113) no IV tPA, p=0.52. The rate of functional independence (90 day mRS 0-2) was 57% with IV tPA vs. 47% without, aOR 1.7 (95% CI 0.95-3.05), p=0.07. The ordinal analysis showed a significant shift towards better 90 day mRS scores in the tPA group, aOR 1.9, 95% CI: 1.19-3.00, p=0.007. Mortality was 11% (tPA) vs 18% (no tPA), p=0.07 and sICH rates were 7% (tPA) vs. 5% (no tPA), p=0.5. Restricting the analyses to patients presenting directly to EVT centers within 4.5 hours (N=115), no significant delays were evident; arrival to puncture with tPA 95 (76-121) min vs 86 (68-114) without tPA, p=0.4. Functional independence was 62% with tPA vs 51% without, aOR 1.73 (95% CI 0.78-3.83, p=0.18) with a statistically significant shift in favor of tPA on the ordinal analysis, aOR 1.8, 95% CI: 1.08-3.45, p=0.038. Patients with M2 occlusions, smaller baseline infarct core volume, earlier treatment, and milder strokes were most likely to have better outcomes with tPA vs no tPA (Fig 1). Conclusion: IV tPA administration did not result in delays to EVT and was associated with higher rates of good outcome. Randomized trials are required to more definitively establish the efficacy of bridging therapy with tPA prior to EVT.