Long-term Outcomes of Hypoplastic Left Heart Syndrome with Analysis of the Norwood Procedure in Infants Following Bilateral Pulmonary Artery Banding

Objective: To investigate the early and long-term outcomes of the deferred Norwood procedure by bilateral pulmonary artery banding (BPAB) versus the neonatal Norwood procedure. Methods: This retrospective study examined 46 patients with hypoplastic left heart syndrome and its variants undergoing the Norwood procedure for single ventricle physiology between 2004 and 2022 at 3 institutions. The patients were divided into 2 groups: neonatal Norwood procedure (group N; n = 23) and staged Norwood procedure in infants following BPAB (group I; n = 23). Preoperative risk factors, surgical results, survival rates, Fontan candidacy, and long-term complications were compared. Results: Early survival rates after the Norwood procedure were 91.3% (21 of 23) in both groups. Late survival rates after the Norwood procedure were similar at the 10-year follow-up (group N, 76.3%; group I, 68.7%; P = .63). Fontan completion rates also were comparable in the 2 groups (group N, 77.8%; group I, 85.7%; P = .67). Group N showed a higher median pulmonary artery (PA) index before bidirectional cavopulmonary connection (group N, 177 [interquartile range (IQR), 147-243] mm2/m2; group I, 152 [IQR, 146-163] mm2/m2; P = .03); this trend continued until 5 years after Fontan completion (P = .01). Group N also had a lower rate of freedom from protein-losing enteropathy (PLE) at 9.0 years after the Fontan operation (90.0% vs 52.5% for group I; P = .04), although the incidences of other Fontan-associated events were not significantly different. Conclusions: Fontan candidacy and survival rates were similar regardless of the timing of the Norwood procedure. Early performance of the Norwood procedure may lead to lower rates of late Fontan-associated events, such as PLE.