Atrioventricular septal defect and aortic arch obstruction: A challenging combination

Objective The combination of atrioventricular septal defect and aortic arch obstruction (AVSD-AAO) is rare and associated with significant morbidity and mortality. We characterized our institutional experience to identify variables influencing surgical strategy and outcomes in this heterogeneous patient population. Methods A retrospective review was performed of all patients undergoing biventricular AVSD repair at Texas Children's Hospital between January 1995 and August 2024. Patients with AVSD-AAO were identified and stratified by age at first intervention (neonates vs infants) and surgical strategy (staged vs concurrent repair). Kaplan-Meier survival estimates, competing risks analysis, and Wilcoxon rank-sum tests were employed for statistical analysis. Results Of 790 AVSD patients, 33 (4.2%) had concurrent AAO. Compared to AVSD without AAO, AVSD-AAO patients had significantly higher cumulative incidence of LAVV reoperation (32.2% vs 14.4%, p=0.0006), LVOTO repair (18% vs 4.7%, p=0.0015), and mortality (15-year survival 77.6% vs 94.2%, p<0.0001). Staged repair with initial arch repair followed by AVSD repair trended toward improved survival compared to concurrent repair (87.8% vs 67.0%, p=0.13). Survival was not different between patients who underwent initial intervention as neonates versus infants (81.9% vs 73.3%, p=0.50). Conclusion AVSD-AAO carries substantially higher rates of reoperation and mortality compared to AVSD alone. AAO is the primary driver of surgical timing due to frequent duct-dependent systemic blood flow; however, neonatal AVSD repair is challenging. Temporizing surgical interventions that optimize systemic and pulmonary blood flow may allow for somatic growth, valve maturation and normalization of pulmonary vascular resistance prior to definitive repair.