Introduction Acute management of ischemic stroke secondary to large vessel occlusion includes IV-thrombolysis (IVT) followed by endovascular thrombectomy (EVT) for eligible patients. Several randomized trials have failed to show non-inferiority of EVT alone to EVT + IVT in patients arriving within the window for IVT, but did demonstrate higher rates of symptomatic hemorrhage (sICH). These studies focused on patients presenting within window for IVT even if EVT happened at later time. In this study, we investigate the impact of IVT on safety and efficacy outcomes of EVT in patients undergoing EVT within 4.5 h of symptom onset.

Methods This is a multicenter retrospective study of patients undergoing EVT for anterior circulation stroke from 46 stroke centers in the United States and globally. Patients 18 years or older were included irrespective of whether IVT was administered. Patients were reviewed for their demographics, admission deficits, and technical outcomes, and were dichotomized to early window (≤4.5 h) and late window (>4.5 h) based on time of arterial puncture. Primary outcome is modified Rankin Score (mRS) at 90 days, secondary outcomes included sICH, embolization to new territory, and successful recanalization. Logistic regression analysis was used with step-wise backpropagation including baseline variables and technique used to compute adjusted odds ratios (aORs) for IVT on outcme measures.

Results Among a total of 10,458 patients were reviewed of which 6516 met criteria for anterior circulation stroke with available follow-up. The mean age was 68 years, and 48% were females. In patients undergoing EVT within 4.5 h of stroke onset, IVT was associated with higher odds of embolization to new territories (aOR= 1.39, 95%CI: 1.08–1.67, p<0.01), higher odds of sICH (aOR=1.5, 95%CI: 1.09–2.1, p=0.012), higher odds of good outcome (aOR=1.3, 95%CI: 1.1–1.6), but no impact on successful recanalization (p=0.512). In patients undergoing EVT after 4.5 h of stroke onset, IVT did not result in higher odds of embolization to new territory or sICH (p>0.1). We then performed a propensity match cohort analysis between patients with IVT use who underwent EVT within 4.5 h versus after 4.5 h. Matching resulted in a cohort of 1378 patients per group with balanced covariates (age, gender, race, comorbidities, baseline mRS, admission NIHSS, ASPECT score, thrombectomy frontline technique, SMD<0.15). Comparing early to late EVT among patients undergoing IVT+EVT, patients in the early window had significantly higher rates of embolization to new territory (OR=1.04, p<0.01) and higher rates of successful recanalization (OR=1.04, p<0.01) compared to late EVT without difference in rates of sICH.

Conclusion This retrospective real-world study demonstrates that in patients considered for EVT who are also eligible for IVT at presentation, bridging therapy is still associated with higher rates of good outcome; however, this group is more likely to be complicated by symptomatic hemorrhage and embolization to new territories.

Disclosures J. Poggi: None. Y. Zohdy: None. B. El Baba: None. F. Akbik: None. B. Howard: None. C. Cawley: None. A. Pabaney: None. F. Tong: None. S. Alkasab: 1; C; Stryker. P. Jabbour: 2; C; Balt, Cerus endovascular, MicroVention, Medtronic. N. Goyal: None. A. Arthur: 1; C; Balt, Microvention, Siemens, Medtronic, Penumbra. 2; C; Arsenal, Johnson and Johnson, Microvention, Scientia, Stryker, Balt, Medtronic, Penumbra, Siemens. 4; C; Azimuth, Cerebrotech, Magneto, Neurogami, Scientia, Synchron, Vastrax, Bendit, Endostream, Mentice, Neuros, Serenity, Tulavi, VizAI. F. Siddiqui: None. S. Yoshimura: None. M. Park: 5; C; Medtronic. W. Brinjikji: None. C. Maatouk: 2; C; Silk Road, Penumbra, Microvention, Stryker. 3; C; Silk Road, Penumbra. D. Romano: None. D. Altschul: None. R. Williamson: None. M. Moss: None. R. De Leacy: 1; C; Hyprevention, Siemens Healthineers, Kaneka Medical, SNIS foundation. 2; C; Stryker Neurovascular, Cerenovus, Imperative Care, Asahi Intec. 4; C; Synchron, Q’Apel, Endostream, Spartan Micro. 6; C; Editorial Board JNIS. M. Ezzeldin: None. P. Kan: 1; C; U18EB029353–01. 2; C; Stryker Neurovascular, Imperative Care, Microvention. 6; C; Editorial Board JNIS. M. Levitt: 1; C; Stryker, Medtronic. 2; C; Medtronic, Aeaean Advisers. 4; C; Hyperion Surgical, Synchron, Fluid Biomed, Proprio, Cerebrotech, Stereotaxis. 6; C; Travel support: Penumbra, Editorial board, Journal of NeuroInterventional Surgery, Metis Innovative: Adviser. R. Grandhi: None. J. Mascitelli: 2; C; Stryker. A. Spiotta: 2; C; Stryker, Terumo, Penumbra, RapidAI. A. Alawieh: 6; C; Penumbra. J. Grossberg: 1; C; Georgia Research Alliance, Emory Medical Care Foundation, Department of Defense, Neurosurgery Catalyst. 4; C; NTI, Cognition.