Abstract A087: Comparison of Short-Term Outcomes of Carotid Artery Stenting versus Endarterectomy in Asymptomatic Carotid Artery Stenosis: A Nationwide Inpatient Database Study in Japan

Background: Uncertainties remain in optimal management of asymptomatic carotid stenosis, including comparative safety of carotid artery stenting (CAS) versus carotid endarterectomy (CEA). Evidence from contemporary clinical practice comparing these interventions remains limited. This study compared in-hospital outcomes of CAS versus CEA in asymptomatic carotid artery stenosis in Japan. Methods: We conducted a retrospective cohort study using Japanese nationwide inpatient database on CAS and CEA from 2019-2021. Asymptomatic status was defined as preadmission modified Rankin Scale (mRS) = 0, Japan Coma Scale = 0, non-emergent admission, and no prior ischemic stroke or transient ischemic attack. One-to-one propensity score matching (PSM) was performed using baseline characteristics to compare in-hospital mortality, perioperative stroke, myocardial infarction, pneumonia, disability at discharge (mRS > 2), and length of stay. After PSM, conditional logistic regression analysis was used to compare outcomes. Prespecified analyses included asymptomatic elderly patients (≥75 years) and overall cohort including symptomatic patients. Results: Of 17,540 CAS and 8,176 CEA procedures (Table 1), 6,086 CAS and 3,159 CEA were asymptomatic. After PSM, 3,154 matched pairs achieved good covariate balance (SMD < 0.1) (Table 2). In asymptomatic patients, conditional logistic regression with CAS as reference revealed no significant differences for mortality (OR 0.48, 95% CI 0.12–1.87; p = 0.286), myocardial infarction (OR 0.72, 95% CI 0.30–1.75; p = 0.472), or disability at discharge (OR 1.19, 95% CI 0.81–1.77; p = 0.377), while CEA was associated with significantly higher pneumonia odds (OR 1.47, 95% CI 1.10–1.96; p = 0.008). CEA also demonstrated longer hospital stay. In elderly asymptomatic patients (≥75 years) (Table 3), CEA had significantly lower stroke odds (OR 0.71, 95% CI 0.52–0.95; p = 0.023) and higher pneumonia odds (OR 1.67, 95% CI 1.08–2.60; p = 0.023), with longer hospital stay. In overall cohort, no significant differences were observed for other outcomes, except for higher pneumonia rates and longer hospital stay with CEA. Conclusions: CAS and CEA demonstrated comparable short-term outcomes in asymptomatic patients, with CAS offering lower pneumonia rates and shorter hospital stay, while CEA showed stroke benefits in elderly patients. These findings suggest need for individualized management approaches.