Double Jeopardy: A Distinct Mortality Pattern Among Preterm Infants with Congenital Heart Disease.

Contemporary United States (US) data on the survival of preterm infants with congenital heart disease (CHD) are unavailable despite the over-representation of CHD and improving surgical outcomes in the preterm population. The aim of this study is to use population-based data to compare 1-year survival and early mortality (< 3 days) by gestational age (GA) between preterm infants with and without cyanotic CHD (CCHD) in the US. This national retrospective cohort included all liveborn, preterm infants between 21 and 36 weeks GA with a birth certificate indicating the presence or absence of CCHD (n = 2,654,253) born between 2014 and 2019 in the US. Data were provided by the US Center for Disease Control database linking birth and death certificates. Of liveborn preterm infants, 0.13% (n = 3619) had CCHD. 1-year survival was significantly lower in infants 23-36 weeks with CCHD compared to those without. The greatest survival gap occurred between 28 and 31 weeks (28 weeks adjusted risk difference 37.5%; 95% CI 28.4, 46.5; 31 weeks 37.9%; 30.5, 45.3). Early mortality accounted for more than half of deaths among infants 23-31 weeks with CCHD (23 weeks-68%, CI 46.7, 83.7; 31 weeks-63.9%, 52.9, 73.6). Survival trends demonstrated worsened 1-year survival in infants 35-36 weeks with CCHD over the study period. The pattern of mortality for preterm infants with CCHD is distinct from those without. The significant survival gap in the very preterm population and notably high rate of early death in the infants with CCHD calls for renewed attention to early neonatal intensive care for this dually affected population.