Single-ventricle reconstruction 2.0: A closer look at our understanding of care for infants undergoing the Norwood procedure

Outcomes Following Norwood Procedures: Analysis of a "Small Volume" Program

BACKGROUND

Institutional survival following Norwood procedures is traditionally correlated with a center's surgical volume. Multiple single and multi-institutional studies conducted at large-volume centers have recently demonstrated improved survival following Norwood procedures. We report both short- and long-term outcomes at a single, small-volume institution and comment on factors potentially influencing outcomes at this institution.

METHODS

All patients undergoing Norwood procedures from January 1, 2005, to January 1, 2020, at our institution were included in this study. Kaplan-Meier survival and Cox regression risk factor analyses were performed in addition to first interstage risk factor scoring to compare observed versus expected survival.

RESULTS

The cohort included 113 patients. Kaplan-Meier freedom from death or transplant was 88%, 80%, and 76% at 1, 5, and 10 years, respectively. Freedom from death following hospital discharge after Norwood procedures was 94%, 87%, and 83% at 1, 5, and 10 years, respectively. The presence of genetic syndromes was a significant risk factor for mortality. First interstage observed-to-expected mortality following discharge was 0.57 (P = .04). Postoperative length of stay was comparable to that reported for the period 2015 to 2018 in the Society of Thoracic Surgeons Database.

CONCLUSIONS

Survival outcomes at this single, small-volume institution were similar to those reported by large-volume centers and multi-institutional collaborative studies. These results may be related to structural and functional features that have been demonstrated to influence outcomes in other studies. These factors are achievable by small-volume programs with sufficient resource allocation.

Evolution of care pathways for babies with hypoplastic left heart syndrome: integrating mechanistic and clinical process investigation, standardization, and collaborative study

Since initial descriptions of staged palliation for hypoplastic left heart syndrome (HLHS) in the 1980’s, much has been learned about the pathophysiology of the single ventricle circulation. New therapies that leverage systems biology and clinical derivatives have been developed. While in-hospital mortality and morbidity for babies with HLHS have continued to improve, there remains a long (and daresay winding) road ahead to achieve ideal outcomes. Important variation in even these abbreviated in-hospital metrics persists among institutions and currently utilized prediction models explain only a small amount of this variation. Moreover, long-term survival and neurodevelopmental health for patients with HLHS are infrequently reported and remain suboptimal despite improved in-hospital outcomes. This focused review will describe the evolution of national outcomes for HLHS over time and the potential factors motivating improved time-related mortality. Emerging modifiable risk-factors that hold promise in terms of moving the needle for long-term success, including social determinants of health and the delineation of genetic profiles, will be discussed. Specifically, this review will integrate contemporary data based on the first murine HLHS models that suggest a genetically elicited modular phenotype with environmental factors known to impact the initial durability of surgical therapies. A comprehensive approach to the management of HLHS, which leverages both proactive transplantation and hybrid palliation, in addition to traditional Norwood palliation, will be emphasized to extend and match management to the complete spectrum of patient risk-profiles. Finally, we will explore the critical role that national collaboratives and quality reporting initiatives have played in improving outcomes and shifting the focus to more meaningful long-term survival and neurodevelopment.

Development of a validated risk score for interstage death or transplant after stage I palliation for single-ventricle heart disease

OBJECTIVE

To develop a risk score to predict mortality or transplant in the interstage period.

BACKGROUND

The "interstage" period between the stage 1 and stage 2 palliation is a time of high morbidity and mortality for infants with single-ventricle congenital heart disease.

METHODS

This was an analysis of patients with single-ventricle congenital heart disease requiring arch reconstruction who were enrolled in the National Pediatric Cardiology Quality Improvement Collaborative registry from 2008 to 2015. The primary composite endpoint was interstage mortality or transplant. Multivariable logistic regression and classification and regression tree analysis were performed on two-thirds of the patients ("learning cohort") to build a risk score for the composite endpoint, that was validated in the remaining patients ("validation cohort").

RESULTS

In the 2128 patients analyzed in the registry, the overall event rate was 9% (153 [7%] deaths, 42 [2%] transplants). In the learning cohort, factors independently associated with the composite endpoint were (1) type of Norwood; (2) postoperative ECMO; (3) discharge with Opiates; (4) No Digoxin at discharge; (5) postoperative Arch obstruction, (6) moderate-to-severe Tricuspid regurgitation without an oxygen requirement, and (7) Extra Oxygen required at discharge in patients with moderate-to-severe tricuspid regurgitation. This model was used to create a weighted risk score ("NEONATE" score; 0-76 points), with >75% accuracy in the learning and validation cohorts. In the validation cohort, the event rate in patients with a score >17 was nearly three times those with a score ≤17.

CONCLUSIONS

We introduce a risk score that can be used post-stage 1 palliation to predict freedom from interstage mortality or transplant.