Abstract DP026: Interaction of Periprocedural Antiplatelets and Intravenous Thrombolysis in Intracranial Stenting for Acute Ischemic Stroke: RESISTANT Registry Subanalysis

Introduction: Intracranial stenting during endovascular thrombectomy (EVT) is a common practice in the setting of failed reperfusion or severe stenosis. Immediate stent patency requires periprocedural antiplatelet therapy (APT). How APT intensity interacts with prior intravenous thrombolysis (IVT) to influence hemorrhagic risk remains uncertain. We aimed to assess whether the APT regimen modifies the association of IVT with early intracranial hemorrhage after intracranial stenting during EVT. Methods: This was a subanalysis of the RESISTANT registry, a multicenter, international, retrospective cohort (2016 to 2023) of adults with acute ischemic stroke who underwent intracranial stenting during EVT. APT regimens were categorized as conservative (intravenous or oral aspirin alone, or aspirin plus an oral P2Y12 inhibitor) and aggressive (any regimen including intravenous GPIIb/IIIa inhibitor or intravenous cangrelor). Four main groups were compared according to the APT regimen (conservative/aggressive) and the use of IVT (+/-). The primary outcome was a composite of sICH and parenchymal hematoma types 1 and 2 (sICH-PH2-PH1). Multivariable logistic regression models were used to evaluate the interaction between IVT and APT, adjusting for clinically relevant covariates. Results: Among the 823 included patients, 44 (5.3%) received conservative APT with IVT, 130 (15.8%) received conservative APT without IVT, 145 (17.6%) received aggressive APT with IVT, and 504 (61.2%) received aggressive APT without IVT. Among patients who received IVT, sICH-PH2-PH1 rates were 9.3% with conservative APT and 10.7% with aggressive APT; among those without IVT, rates were 3.2% and 9.9%, respectively. Administration of IVT (adjusted odds ratio [aOR] 5.84, 95%CI 1.07 to 43.92; p=0.05) and aggressive APT (aOR 4.81, 95% CI 1.41 to 30.22; p=0.03) were each associated with higher odds of hemorrhagic complications, with a significant IVT by APT interaction (P interaction =0.05; Figures 1 and 2 ). Within the aggressive APT plus IVT subgroup, sICH-PH2-PH1 occurred in 20% of patients treated with cangrelor and 6.1% treated with a glycoprotein IIb/IIIa inhibitor ( Figure 3 ). Conclusion: Among patients requiring intracranial stenting, aggressive periprocedural APT and prior IVT are each associated with higher hemorrhagic risk, with the combination showing the worst observed crude outcome. Prospective evaluation of protocolized APT pathways in the IVT setting is warranted.