Shifting strategies to address systemic outflow tract obstruction in single ventricle anatomy with transposed great arteries.

Abstract

Double inlet left ventricle and tricuspid atresia both with transposed great arteries are at risk of systemic outflow tract obstruction. This study aimed to document evolving management strategies for these substrates and compare historical versus contemporary surgical approaches on long-term Fontan outcomes. A retrospective study of patients with double inlet left ventricle-transposed great arteries/tricuspid atresia-transposed great arteries who underwent single ventricle palliation in Australia and New Zealand from 1965 to 2023 was conducted using the Fontan Registry. Participants were divided into 2 groups: those who received their Glenn procedure before 2005 (or born before 2005 if no Glenn performed; group A) and those from 2005 onward (group B). Overall, 163 patients with double inlet left ventricle-transposed great arteries and 95 patients with tricuspid atresia-transposed great arteries were identified. Group B had a higher proportion of patients (50%) who underwent aggressive palliation (eg, Damus-Kaye-Stansel, palliative arterial switch, or Norwood) compared with group A (32.0%; P = .007). In group B, these procedures were performed earlier (77.5% aged <1 year vs 43.9% in group A; P = .004) and performed preemptively without documented systemic outflow tract obstruction (75% vs 35%; P = .036). Median follow-up for groups A and B was 27.5 and 10.1 years, respectively. Transplant-free survival was 93.1% at 15 years for group A and 100% for group B (P = .05). Cumulative incidence of systemic outflow tract obstruction reintervention was 22.7% at 15 years for group A compared with 1.5% for group B (P = .0001). Surgical palliation strategies have shifted significantly to earlier, more aggressive palliation since 2005. This has likely contributed to a significant reduction in systemic outflow tract obstruction reintervention.