Not To Skip Yet: Impact of Intravenous Thrombolysis on Final Infarction Volume and Clinical Outcomes in early Arrivals Acute Large Vessel Occlusion: A Retrospective Cohort Study

Background Combination of intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) is still the standard of care for select patients with acute large vessel occlusion (LVO) stroke within 4.5-hours of last known well (LKW). However, the impact of bridging therapy on clinical outcomes for eligible patients who present directly to comprehensive stroke centers (CSC) remains controversial. Methods This is a retrospective cohort obtained from Get With The Guidelines-Stroke Database available at the Medical University of South Carolina CSC for LVO patients who presented within 4.5-hours-of-LKW between January/2018 and June/2022. This study aimed to evaluate the benefit of IVT in reducing the final infarction volume (FIV) after complete recanalization. Results Of 220 patients who presented with LVO and had complete recanalization (mTICI2c/3), 100 (45%) arrived within 4.5 hours of LKW and 39 patients (39%) received IVT in addition to mechanical thrombectomy (IVT-MT). IVT-MT group had a smaller final infarct volume (FIV) than the MT-only group (7cc vs.16 cc, p=0.03). IVT was associated with 26cc reduction in FIV 95%CI [-45.7, -6.80), p=0.009). This effect was modified by the Collaterals score for anterior LVO 11cc 95%CI [-20.33- -1.92]. FIV influenced discharge NIHSS 3.095 95%CI [0.030-0.136], p= 0.003, and 90-day functional independence mRS (0-2) aOR 0.98 95%CI [0.96-0.99], p=0.022. Consequently, the IV-MT group had better 24-hours NIHSS 2 IQR (0-5) vs. 6 (2-13) p= 0.034, better discharge NIHSS 2 IQR (0-2) vs. 4 (1-11) p= 0.048, and more proportion of patients achieved functional independence at 90-days 32% vs. 10% however this difference did not reach statistical significance p=0.41. Conclusion This study suggests that the combined IVT-MT approach can benefit LVO patients beyond the drip and ship model. IVT potentiates the effect of successful recanalization via the reduction of FIV and subsequent improved outcomes ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial This is a retrospective cohort and was not registered in clinicaltrials.gov ### Funding Statement Funding was through the department of neurology at MUSC ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: MUSC institutional IRB board I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data is available upon request from the corresponding author * LVO : Large vessel occlusion IVT : Intravenous thrombolysis ASPECTS : Alberta Stroke Program Early CT Score LKW : Last Known well. CSC : Comprehensive stroke center. mTICI score : Modified treatment in cerebral ischemia FIV : Final infarction volume