Atrioventricular septal defect and aortic arch obstruction: A challenging combination

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 the surgical strategy and outcomes in this heterogeneous patient population.

A retrospective review was performed on 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 in statistical analysis.

Of 790 AVSD patients, 33 (4.2%) had concurrent AAO. Compared to AVSD without AAO, AVSD-AAO patients had significantly higher cumulative incidence of a left atrioventricular valve reoperation (32.2% vs 14.4%, P = .0006), left ventricular outflow flow tract obstruction repair (18% vs 4.7%, P = .0015), and the mortality (15-year survival, 77.6% vs 94.2%, P < .0001). Staged repair with an initial arch repair followed by AVSD repair trended toward improved survival compared to concurrent repair (87.8% vs 67.0%, P = .13). Survival was not different between patients who underwent an initial intervention as neonates versus infants (81.9% vs 73.3%, P = .50).

AVSD-AAO carries substantially higher rates of reoperation and mortality compared with AVSD alone. AAO is the primary driver of surgical timing due to the 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, the valve maturation, and the normalization of pulmonary vascular resistance prior to definitive repair.