Outcomes of Delayed Norwood Operation in High-Risk Patients—Time to Reconsider the Dogma of a Primary Norwood Operation?

Abstract

Abstract Objectives The delayed Norwood (DN) approach, preceded by bilateral pulmonary artery banding (bPAB), has emerged as a strategy to improve outcomes in high-risk infants by addressing neonatal haemodynamic instability and organ immaturity. Methods This single-centre, retrospective study analysed 20 consecutive patients with hypoplastic left heart syndrome/variants and multiple risk factors who underwent a DN operation following bPAB between 2019 and 2024. Results Bilateral pulmonary artery banding was performed at a median age of 2.5 days (interquartile range [IQR]: 2-4). Preoperative risk factors included prematurity (35%), low birth weight <2.5 kg (25%), non-cardiac comorbidities (25%), genetic syndromes (50%), preoperative cardiogenic shock (35%), and restrictive atrial septum (25%). The median age at DN was 36 days (IQR: 29-79), with an operative survival rate of 75%. Patients who underwent the DN within 4 weeks of bPAB did not require any pulmonary artery (PA) reinterventions. Median lactate clearance time was 8 hours (IQR: 5-18), and the median vasoactive inotropic score decreased by 47% within 48 hours postoperatively. Cerebral near-infrared spectroscopy values improved in patients without postoperative extracorporeal membrane oxygenation (ECMO) support from 53% to 58% and 63% at 0, 12, and 36 hours, respectively. Conclusions The DN approach, preceded by initial bPAB in a high-risk patient cohort, achieved surgical outcomes comparable to those of lower-risk patients undergoing primary Norwood operation. A DN procedure around 4-6 weeks of following bPAB may improve survival rates in high-risk patients with a reduction in surgical or catheter-based reinterventions.