Single Ventricle Infant Deaths Without Transplant Referral: Room for Improvement?

Infants with hypoplastic left heart syndrome undergoing single ventricle (SV) palliation may need early heart transplant, but optimal referral timing is unknown, and referrals may be inequitable. We performed a retrospective study of infants undergoing stage 1 SV palliation (S1P) from 2016-2022 enrolled in the National Pediatric Cardiology-Quality Improvement Collaborative (NPC-QIC). Competing risk methods were used to evaluate predictors of Transplant Referral (TxR) and death without TxR. Neighborhood opportunity was determined through use of Child Opportunity Index (COI). A total of 2,960 infants were included. Infants from lower opportunity neighborhoods had lower median birth weights, were less likely to be prenatally diagnosed, and were more likely to require mechanical ventilation pre-operatively than those from higher opportunity neighborhoods. At one year, an estimated 79% of infants were alive, 16% had died, and 5% had a TxR, with no differences in outcomes by neighborhood opportunity or race. In multivariable analysis, neither neighborhood opportunity nor race was associated with either outcome when controlling for known risk factors. Pre-operative tricuspid regurgitation was most predictive of TxR and was also a major risk factor for death without TxR. Multiple non-cardiac risk factors were predictive of death without TxR. One-year survival after S1P approached 80%, though death without TxR was three times more common than TxR. No clear disparities were seen, though non-cardiac risk factors for death were more prevalent in those from lower opportunity neighborhoods. Standardized guidelines may help identify high risk infants who may benefit from earlier TxR.