Cerebral and end-organ protection outcomes following the Norwood procedure: A retrospective cohort study

Background: Hypoplastic left heart syndrome (HLHS) remains one of the most challenging congenital heart defects, and the Norwood procedure is the cornerstone of first-stage palliation. Two perfusion strategies - deep hypothermic circulatory arrest (DHCA) and selective antegrade cerebral perfusion (SACP) - are widely used during aortic arch reconstruction. However, comparative evidence regarding cerebral and end-organ protection in neonates is inconsistent. Objectives: To evaluate end-organ protection outcomes associated with SACP versus DHCA during the Norwood procedure. Methods: We conducted a retrospective single-center cohort study of 93 neonates with HLHS undergoing the Norwood procedure between 2014 and 2025. Patients were divided into two groups: DHCA (n = 45) and SACP (n = 48). Primary endpoint was acute kidney injury (AKI) according to pediatric KDIGO criteria. Secondary endpoints included hospital mortality, neurological injuries. Results: Overall hospital mortality was 15 % (DHCA 17.7 % vs. SACP 12.5 %, p = 0.566). Ischemic brain lesions were significantly more frequent in the DHCA group (17.8 %) compared to the SACP group (2.1 %, p = 0.013). DHCA duration >45 min identified as a key risk factor of ischemic injury (HR 1.08, 95 % CI 1.02–1.14, p = 0.003). Hemorrhagic brain lesions occurred in 4.4 % (DHCA) vs. 10.4 % (SACP, p = 0.436), low body weight < 2.6 kg was an independent predictor. AKI incidence was higher in the DHCA group (55.5 %) than in the SACP group (33.3 %, p = 0.038). SACP was associated with a lower AKI risk (HR 0.32, 95 % CI 0.12–0.84, p = 0.047), while a vasoactive-inotropic score > 10 within 48 h predicted AKI (HR 1.03, 95 % CI 1.01–1.07, p = 0.019). Conclusions: In neonates undergoing the Norwood procedure, SACP was associated with lower rates of AKI and ischemic cerebral injury compared to DHCA. Perfusion strategy choice should be considered alongside patient risk factors to optimize outcomes.