Clinical Outcomes and Risk Factors for In-Hospital Mortality in Neonates with Hypoplastic Left Heart Syndrome

The objective of this study was to identify patient and hospitalization characteristics associated with in-hospital mortality in infants with hypoplastic left heart syndrome (HLHS). We conducted a retrospective analysis of a large administrative database, the National Inpatient Sample dataset of the Healthcare Cost and Utilization Project for the years 2002-2016. Neonates with HLHS were identified by ICD-9 and ICD-10 codes. Hospital and patient factors associated with inpatient mortality were analyzed. Overall, 18,867 neonates met the criteria of inclusion; a total of 3813 patients died during the hospitalization (20.2%). In-hospital mortality decreased over the years of the study (27.0% in 2002 vs. 18.3% in 2016). Extracorporeal membrane oxygenation utilization was 8.1%. Univariate and multivariate logistic regression analyses were used to identify risk factors for in-hospital mortality in infants with hypoplastic left heart syndrome. Independent non-modifiable risk factors for mortality were birth weight < 2500 g (Adjusted odds ratio (aOR) 2.16 [1.74-2.69]), gestational age < 37 weeks (aOR 1.73 [1.42-2.10]), chromosomal abnormalities (aOR 3.07 [2.60-3.64]) and renal anomalies (aOR 1.34 [1.10-1.61]). Independent modifiable risk factors for mortality were being transferred-in from another hospital (aOR 1.15 [1.03-1.29]), use of extracorporeal membrane oxygenation (aOR 12.74 [10.91-14.88]). Receiving care in a teaching hospital is a modifiable variable, and it decreased the odds of mortality (aOR 0. 78 [0.64-0.95]). In conclusion, chromosomal anomalies, Extra Corporeal Membrane Oxygenation, gestational age < 37 weeks or birth weight < 2500 g were associated with increased odds of mortality. Modifiable variables as receiving care at birth center and in a hospital designated as a teaching hospital decreased the odds of mortality.