Characterizing Neonatal Outcomes of Cardiac Procedures Using the National Database

By Hany Aly, MD

Most common cyanotic congenital heart defect

Transposition of the great arteries (TGA) is the most common cyanotic congenital heart defect in neonates.1 Due to the ventriculoarterial discordance and atrioventricular concordance that occurs with TGA, creating a parallel circulation, the current medical approach focuses on stabilization and an early arterial switch operation. However, insufficient mixing and severe hypoxemia may require urgent intervention with balloon atrial septostomy (BAS) to improve oxygenation until surgery can occur.1

Database studies help inform benchmarks

In collaboration with other members of Cleveland Clinic Children’s neonatal cardiac critical care research team, including Mohammed Hamzah, MD, Hasan Othman, MD, Allison Peluso, MD, and Ibrahim Sammour, MD, we recently conducted a study with the main objective to compare the characteristics, outcomes and mortality risks in patients with TGA who underwent BAS during their hospitalization versus TGA patients who have not undergone this procedure.2 To do this, we utilized deidentified patient data produced from the Healthcare Cost and Utilization Project. We used the Kids’ Inpatient Database (KID), complemented with the National Inpatient Sample (NIS) database.

By utilizing these large databases, we were able to access patient data from more than 17,000 neonates with TGA, of which 27% had BAS.2 There was no statistical difference in the mortality rate of TGA patients with and without BAS. However, comparison of in-hospital mortality with and without BAS revealed increased mortality risk in no-BAS patients transferred from other institutions. Furthermore, extracorporeal membrane oxygenation (ECMO) was more likely to be utilized in no-BAS patients. However, BAS was associated with increased risk for stroke. The association of BAS and stroke was significant in all TGA patients regardless of being supported or not supported with ECMO. Finally, length of hospital stay and cost of hospital charges were higher in BAS patients.2

Utilizing the same national dataset, the neonatal cardiac critical care team conducted two additional studies with the aim to identify patient and hospitalization characteristics associated with in-hospital mortality for infants with truncus arteriosus3 and hypoplastic left heart syndrome (HLHS).4 The analyses for truncus arteriosus included more than 3,000 infants; 27% of them had 22q11.2 deletion syndrome (DiGeorge syndrome). Interestingly, 22q11.2 deletion was associated with decreased mortality compared to subjects without this deletion. However, DiGeorge syndrome was associated with higher incidence of noncardiac anomalies, higher utilization of tracheostomy and G‐tube placement, and protracted length of stay with increased cost of hospitalization.3 Significant risk factors for mortality in infants with truncus arteriosus were prematurity (adjusted odds ratio [aOR] = 2.43; 95% confidence interval [CI]: 1.40‐4.22; P = 0.002), diagnosis of stroke (aOR = 26.a2; 95% CI: 10.1‐68.1; P < 0.001), necrotizing enterocolitis (aOR = 3.10; 95% CI: 1.24‐7.74; P = 0.015) and presence of venous thrombosis (aOR = 13.5; 95% CI: 6.7‐27.2; P < .001). Patients who were supported with ECMO or had a cardiac catheterization procedure during the hospitalization had increased odds of mortality (aOR = 82.0; 95% CI: 44.5‐151.4; P < 0.001, and aOR = 1.65; 95% CI: 0.98‐2.77; P = 0.060, respectively).

In the HLHS study, we analyzed the data on 20,649 neonates. We compared the patient characteristics in two epochs: 1998-2005 and 2006-2014. The recent epoch was associated with 20% decrease in mortality (from 25.3% to 20.6%, p < 0.001) and 31% decrease in the use of BS (23.3% vs. 16.1%, p < 0.001). Risk factors associated with increased mortality in HLHS patients included chromosomal anomalies, utilization of ECMO and gestational age < 37 weeks or birth weight < 2,500 g.4

In studies such as these, the main strengths include the large sample size, time span and geographical homogeneity. Using data from a multicenter national database with a large number of patients and a wide range of practice variations allows us to evaluate outcomes better and identify factors associated with infant mortality. The type of data is always helpful in providing actual benchmarks that can be used as a resource when providing prenatal and postnatal counseling to parents of fetuses and infants with rare congenital heart diseases. Future studies are needed to identify modifiable risk factors to possibly decrease mortality and ameliorate the risk of associated complications.

References

1. Hoffman JI, Kaplan S. The incidence of congenital heart disease. J Am Coll Cardiol. 2002;39:1890–1900.
2. Hamzah M, Othman HF, Peluso AM, Sammour I, Aly H. Prevalence and outcomes of balloon atrial septostomy in neonates with transposition of great arteries. Pediatr Crit Care Med. 2020;21(4):324-331.
3. Hamzah M, Othman HF, Daphtary K, Komarlu R, Aly H. Outcomes of truncus arteriosus repair and predictors of mortality. J Card Surg. 2020;35(8):1856-1864.
4. Hamzah M, Othman HF, Elsamny E, Agarwal H, Aly H. Clinical outcomes and risk factors for in-hospital mortality in neonates with hypoplastic left heart syndrome. Pediatr Cardiol. 2020;41(4):781-788.

About the author

Dr. Aly is Chair of the Department of Neonatology and Professor of Pediatrics at Cleveland Clinic Lerner College of Medicine of Case Western Reserve University.