Abstract
OBJECTIVE: To evaluate risk factors for mortality and discharge timing in preterm infants born before 35 weeks' gestational age (GA) with congenital heart disease (CHD).
STUDY DESIGN: Retrospective cohort study using Children's Hospitals Neonatal Consortium data from 2010-2024. Infants <35 weeks' GA with CHD were included. Primary and secondary outcomes were in-hospital mortality and post-menstrual age (PMA) at discharge. CHD subtypes were categorized as compromised systemic output, sustained cyanosis, or congestive heart failure. Multivariable generalized linear mixed models were used.
RESULTS: Among 11,261 preterm infants with CHD, mortality was 13.7%. Significant interactions between CHD subtype and gestational age were observed. Among infants with congestive heart failure, those 30-32 weeks' GA had higher mortality compared with <27 weeks' GA (adjusted odds ratio [aOR] 1.46, 95% confidence interval [CI], 1.06-2.02, p=0.012), and those 27-29 weeks GA had lower mortality odds compared with 30-32 weeks (aOR 0.69, 95% CI, 0.52-0.90, p=0.002). Surgical necrotizing enterocolitis, delivery room intubation, and trisomy 21 were the strongest mortality predictors (aOR 3.12, 2.69 and 2.27, respectively; all p<0.001). Higher GA was associated with earlier PMA at discharge (-2.4 weeks for 30-32 weeks GA vs <27 weeks GA; p<0.001).
CONCLUSIONS: Short-term outcomes vary by CHD subtype and comorbidities. Older GA was unrelated to inpatient mortality. Potentially modifiable factors such as necrotizing enterocolitis and infections could inform care. Future work incorporating prenatal decisions and surgical timing is needed.