P0414 - Testing the Single Ventricle NEONATE Scoring system: Can it identify infants at high risk for Interstage Mortality and Transplant in our patient population?

Background
Infants born with single right ventricle congenital heart disease (SVCHD) physiology, such as hypoplastic left heart syndrome and variants, are at a high risk for death or transplant during the interstage (IS) defined as the period between Stage 1 surgery (aorto-pulmonary shunt with arch reconstruction) and Stage 2 surgery (superior cavopulmonary anastomosis). The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) has recently proposed the NEONATE score to identify those patients at highest risk for interstage mortality or transplant. We tested the validity of this score in our population.
Objectives
To test the ability of the NEONATE score in identifying poor outcomes in patients with SVCHD physiology (death or transplant during IS) followed by our program over the last 10 years.
Methods
All patients with SVCHD disease who were enrolled by our interstage monitoring program (IMP) and completed the interstage period between May 2009 and April 2020 were included. We excluded patients who either died prior to Stage 1 surgery or were never discharged during interstage. Data was collected on components of the NEONATE score at the time of stage 1 hospital discharge [N=Norwood surgery type, E= post-operative ECMO, O=opioids, N=No digoxin, A=arch obstruction, T ≥moderate tricuspid regurgitation (TR) and E=Extra Oxygen with ≥ moderate TR]. NEONATE score categories included low risk (score <12), medium risk (13 to 17) and high risk (score ≥ 17) for poor IS outcomes. A positive test was defined as NEONATE score ≥ 17. Groups with poor and good outcomes were compared using standard statistical tests.
Results
A total of 113 newborns from May 2009 to April 2020 with SVCHD disease were identified. Twenty-four patients were excluded (death before Stage 1: n=4, never discharged after Stage 1 surgery: n=20). Of the 93 study subjects, 13 (14%) had poor IS outcomes. Of those patients with a clinically poor outcome, 77% (n=10) had a high NEONATE score ≥ 17, compared to 32.5% of those with good outcomes (n=26; p=0.004). Overall, 36/93 patients (39%) had a NEONATE score ≥ 17 and had a significantly higher rate of poor IS outcome (10/36 vs 3/57, p=0.004). The NEONATE score ≥17 (positive test) had an overall sensitivity of 77% and specificity of 68% in identifying patients likely to have death or transplant during interstage.
Conclusions
The NEONATE score ≥ 17 had a high sensitivity but relatively lower specificity in identifying infants who had poor outcomes during the inter-stage period at our institution in the last 10 years. Nevertheless, this is a useful and promising tool to guide management and allocation of resources to this vulnerable group during the critical interstage period. Longitudinal studies are necessary to study the impact of this score on improving future outcomes.