Early Left Ventricular Dysfunction and Severe Pulmonary Hypertension Predict Adverse Outcomes in Low-Risk Congenital Diaphragmatic Hernia

Objectives: Given significant focus on improving survival for high-risk congenital diaphragmatic hernia, there is the potential to overlook the need to identify risk factors for suboptimal outcomes in low-risk congenital diaphragmatic hernia cases. We hypothesized that early cardiac dysfunction or severe pulmonary hypertension were predictors of adverse outcomes in this low-risk congenital diaphragmatic hernia population. Design: This is a retrospective cohort study using data from the Congenital Diaphragmatic Hernia Study Group registry. Low-risk congenital diaphragmatic hernia was defined as Congenital Diaphragmatic Hernia Study Group defect size A/B without structural cardiac and chromosomal anomalies. Examined risk factors included left ventricular dysfunction, right ventricular dysfunction, and severe pulmonary hypertension on the first postnatal echocardiogram. The primary outcome was composite adverse events, defined as either death, extracorporeal membrane oxygenation utilization, oxygen requirement on day 30 of life, or hospitalization greater than or equal to 8 weeks. Multivariable adjustment was performed with logistic regression and inverse probability weighting. Setting: Neonatal index hospitalization for congenital diaphragmatic hernia. Patients: Low-risk congenital diaphragmatic hernia infants born between January 2015 and December 2018. Interventions: First postnatal echocardiogram performed within 24 hours from birth. Measurements and Main Results: Seven-hundred seventy-eight patients were identified as low-risk congenital diaphragmatic hernia. Left ventricular dysfunction, right ventricular dysfunction, and severe pulmonary hypertension were present in 10.8%, 20.5%, and 57.5%, respectively. The primary outcome occurred in 21.3%. Death occurred in 3.0% and 9.1% used extracorporeal membrane oxygenation. On unadjusted analysis, all three risk factors were associated with the primary outcome. On all multivariable adjustment methods, left ventricular dysfunction and severe pulmonary hypertension remained significant predictors of adverse outcomes while right ventricular dysfunction no longer demonstrated any effect. Conclusions: Early left ventricular dysfunction and severe pulmonary hypertension are independent predictors of adverse outcomes among low-risk congenital diaphragmatic hernia infants. Early recognition may lead to interventions that can improve outcome in this at-risk cohort.