Refining The Society of Thoracic Surgeons Congenital Heart Surgery Database Mortality Risk Model With Enhanced Risk Adjustment for Chromosomal Abnormalities, Syndromes, and Noncardiac Congenital Anatomic Abnormalities

Impact of heart failure on reoperation in adult congenital heart disease: An innovative machine learning model

OBJECTIVES

The study objectives were to evaluate the association between preoperative heart failure and reoperative cardiac surgical outcomes in adult congenital heart disease and to develop a risk model for postoperative morbidity/mortality.

METHODS

Single-institution retrospective cohort study of adult patients with congenital heart disease undergoing reoperative cardiac surgery between January 1, 2010, and March 30, 2022. Heart failure defined clinically as preoperative diuretic use and either New York Heart Association Class II to IV or systemic ventricular ejection fraction less than 40%. Composite outcome included operative mortality, mechanical circulatory support, dialysis, unplanned noncardiac reoperation, persistent neurologic deficit, and cardiac arrest. Multivariable logistic regression and machine learning analysis using gradient boosting technology were performed. Shapley statistics determined feature influence, or impact, on model output.

RESULTS

Preoperative heart failure was present in 376 of 1011 patients (37%); those patients had longer postoperative length of stay (6 [5-8] vs 5 [4-7] days, P < .001), increased postoperative mechanical circulatory support (21/376 [6%] vs 16/635 [3%], P = .015), and decreased long-term survival (84% [80%-89%] vs 90% [86%-93%]) at 10 years (P = .002). A 7-feature machine learning risk model for the composite outcome achieved higher area under the curve (0.76) than logistic regression, and ejection fraction was most influential (highest mean |Shapley value|). Additional risk factors for the composite outcome included age, number of prior cardiopulmonary bypass operations, urgent/emergency procedure, and functionally univentricular physiology.

CONCLUSIONS

Heart failure is common among adult patients with congenital heart disease undergoing cardiac reoperation and associated with longer length of stay, increased postoperative mechanical circulatory support, and decreased long-term survival. Machine learning yields a novel 7-feature risk model for postoperative morbidity/mortality, in which ejection fraction was the most influential.

Clinical Risk Assessment and Prediction in Congenital Heart Disease Across the Lifespan: JACC Scientific Statement

Congenital heart disease (CHD) comprises a range of structural anomalies, each with a unique natural history, evolving treatment strategies, and distinct long-term consequences. Current prediction models are challenged by generalizability, limited validation, and questionable application to extended follow-up periods. In this JACC Scientific Statement, we tackle the difficulty of risk measurement across the lifespan. We appraise current and future risk measurement frameworks and describe domains of risk specific to CHD. Risk of adverse outcomes varies with age, sex, genetics, era, socioeconomic status, behavior, and comorbidities as they evolve through the lifespan and across care settings. Emerging technologies and approaches promise to improve risk assessment, but there is also need for large, longitudinal, representative, prospective CHD cohorts with multidimensional data and consensus-driven methodologies to provide insight into time-varying risk. Communication of risk, particularly with patients and their families, poses a separate and equally important challenge, and best practices are reviewed.

Comparing apples to apples: Exploring public reporting of congenital cardiac surgery outcomes based on common congenital heart operations

OBJECTIVE

We sought to simplify reporting of outcomes in congenital heart surgery that compares well-defined patient groups and accommodates multiple stakeholder needs while being easily understandable.

METHODS

We selected 19 commonly performed congenital heart surgeries ranging in complexity from repair of atrial septal defects to the Norwood procedure. Strict inclusion/exclusion criteria ensured the creation of 19 well-defined diagnosis/procedure cohorts. Preoperative, procedural, and postoperative data were collected for consecutive eligible patients from 9 centers between January 1, 2016, and December 31, 2021. Unadjusted operative mortality rates and hospital length of stay for each of the 19 diagnosis/procedure cohorts were summarized in aggregate and stratified by each center.

RESULTS

Of 8572 eligible cases included, numbers in the 19 diagnosis/procedure cohorts ranged from 73 for tetralogy of Fallot repair after previous palliation to 1224 for ventricular septal defect (VSD) repair for isolated VSD. In aggregate, the unadjusted mortality ranged from 0% for atrial septal defect repair to 28.4% for hybrid stage I. There was significant heterogeneity in case mix and mortality for different diagnosis/procedure cohorts across centers (eg, arterial switch operation/VSD, n = 7-42, mortality 0%-7.4%; Norwood procedure, n = 16-122, mortality 5.3%-25%).

CONCLUSIONS

Reporting of institutional case volumes and outcomes within well-defined diagnosis/procedure cohorts can enable centers to benchmark outcomes, understand trends in mortality, and direct quality improvement. When made public, this type of report could provide parents with information on institutional volumes and outcomes and allow them to better understand the experience of each program with operations for specific congenital heart defects.

The Society of Thoracic Surgeons Congenital Heart Surgery Database: 2023 Update on Outcomes and Research

The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (CHSD) continues to be the most comprehensive database of congenital and pediatric cardiothoracic surgical procedures in the world and contains information on 664,210 operations as of June 30, 2023. The 35th harvest of the STS CHSD data was undertaken in Spring 2023, spanning the 4-year period January 1, 2019, through December 31, 2022, and included 144,919 operations performed at 114 participating sites in North America. The harvest analysis was successfully executed by the STS Research and Analytic Center. The overall unadjusted mortality rate was 2.68% and has remained stable over the 4 years included in the current harvest window. Mortality is highest in neonates (7.4%) and lowest in children (1.1%). As in prior analyses, observed mortality and postoperative length of stay in the database increase with an increase in STS-European Association for Cardio-Thoracic Surgery (STAT) Congenital Heart Surgery Mortality Categories. This quality report summarizes contemporary outcomes, provides the odds ratios for the CHSD risk model variables based on this analysis, and describes on-going efforts to improve data collection and augment analytical approaches. Lastly, 5 research publications completed in the last year using data from the CHSD are also summarized.

The American Association for Thoracic Surgery (AATS) 2023 Expert Consensus Document: Recommendation for the care of children with trisomy 13 or trisomy 18 and a congenital heart defect

OBJECTIVES

Recommendations for surgical repair of a congenital heart defect in children with trisomy 13 or trisomy 18 remain controversial, are subject to biases, and are largely unsupported with limited empirical data. This has created significant distrust and uncertainty among parents and could potentially lead to suboptimal care for patients. A working group, representing several clinical specialties involved with the care of these children, developed recommendations to assist in the decision-making process for congenital heart defect care in this population. The goal of these recommendations is to provide families and their health care teams with a framework for clinical decision making based on the literature and expert opinions.

METHODS

This project was performed under the auspices of the AATS Congenital Heart Surgery Evidence-Based Medicine Taskforce. A Patient/Population, Intervention, Comparison/Control, Outcome process was used to generate preliminary statements and recommendations to address various aspects related to cardiac surgery in children with trisomy 13 or trisomy 18. Delphi methodology was then used iteratively to generate consensus among the group using a structured communication process.

RESULTS

Nine recommendations were developed from a set of initial statements that arose from the Patient/Population, Intervention, Comparison/Control, Outcome process methodology following the groups' review of more than 500 articles. These recommendations were adjudicated by this group of experts using a modified Delphi process in a reproducible fashion and make up the current publication. The Class (strength) of recommendations was usually Class IIa (moderate benefit), and the overall level (quality) of evidence was level C-limited data.

CONCLUSIONS

This is the first set of recommendations collated by an expert multidisciplinary group to address specific issues around indications for surgical intervention in children with trisomy 13 or trisomy 18 with congenital heart defect. Based on our analysis of recent data, we recommend that decisions should not be based solely on the presence of trisomy but, instead, should be made on a case-by-case basis, considering both the severity of the baby's heart disease as well as the presence of other anomalies. These recommendations offer a framework to assist parents and clinicians in surgical decision making for children who have trisomy 13 or trisomy 18 with congenital heart defect.

Contemporary Relationship Between Hospital Volume and Outcomes in Congenital Heart Surgery

BACKGROUND

Studies examining the volume-outcome relationship in congenital heart surgery (CHS) are more than a decade old. Since then, mortality has declined, and case-mix adjustment has evolved. We determined the current relationship between hospital CHS volume and outcomes.

METHODS

Patients aged ≤18 years undergoing index operations in The Society of Thoracic Surgeons-Congenital Heart Surgery Database (2017-2020) were included. Associations between annual hospital volume and case-mix-adjusted operative mortality, major complications, failure to rescue (FTR), and postoperative length of stay (PLOS) were assessed using Bayesian hierarchical models, overall, by The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) category, and for the Norwood procedure.

RESULTS

Across 101 centers (76,714 index operations), median annual volume was 144 operations/y. Operative mortality was 2.7%. Lower-volume hospitals had higher mortality, with an apparent transition zone at ∼190 operations/y (95% credible interval [CrI], 115-450 operations/y), below which a sustained uptick in the estimated odds of death occurred. Odds of death compared with a 450 operations/y reference were 50 operations/y (odds ratio [OR], 1.84; 95% CrI, 1.41-2.37), 100 operations/y (OR, 1.37; 95% CrI, 1.08-1.71), 200 operations/y (OR, 0.92; 95% CrI, 0.1-1.18), 300 operations/y (OR, 0.89; 95% CrI, 0.76-1.04). The volume-outcome effect was more apparent for STAT 4 to 5 than STAT 1 to 3 operations. In the overall cohort, PLOS and complications were similar across hospital volumes, whereas FTR rates were higher at lower-volume hospitals. Lower-volume hospitals had worse outcomes after the Norwood procedure, most notably mortality and FTR.

CONCLUSIONS

Hospital volume is associated with mortality and FTR after CHS. The relationship is strongest for high-risk operations. These data can inform ongoing initiatives to improve CHS care.

Noncardiac anomalies in children with congenital heart disease

Introduction

Noncardiac anomalies (NCAs) in patients with congenital heart defects (CHDs) are crucial for perioperative management and etiology studies. This study aimed to investigate NCAs in Chinese children with CHDs.

Methods

Medical records for CHD-diagnosed children hospitalized from 1 January 2015 to 31 December 2019 were collected and subjected to retrospective analyses to excavate potential association rules between CHDs and noncardiac malformations.

Results

A total of 3,788 CHD patients were included in this study. The main phenotypes of CHD were Ventricular Septal Defect (VSD, 33.69%), Atrial Septal Defect (ASD, 12.72%), and Tetralogy of Fallot (TOF, 5.54%). A total of 887 (23.42%) cases showed noncardiac anomalies, which were mainly associated with the central nervous system (34.61%), nose/ear/mandibular/face (19.39%), genitourinary system (15.78%), and musculoskeletal system (15.56%). Compared to other CHD subtypes, septal defects had a lower percentage of associated NCAs (P = 3.7 × 10-9) while AVSD had a higher percentage (P = 0.0018).

Disscussion

NCAs are prevalent among CHD-diagnosed children in China, and the spectrums of NCAs in different CHD subcategories were different.

The common trisomy syndromes, their cardiac implications, and ethical considerations in care

PURPOSE OF REVIEW

To review the incidence of congenital heart disease in the trisomies, highlight the history of cardiac surgery in trisomy 21 comparing it to the increase in cardiac surgery in trisomies 13 and 18, discuss ethical issues specific to trisomies 13 and 18, and suggest a pathway of shared decision-making in the management of congenital heart disease in trisomy 13 and 18, specifically congenital heart surgery.

RECENT FINDINGS

Congenital heart disease is prevalent in the trisomies and the management of these defects, especially surgical intervention, has changed. In the late 20th century, survival after cardiac surgery in trisomy 21 vastly improved, significantly decreasing morbidity and mortality secondary to pulmonary hypertension. Similarly, procedures and surgeries have been performed with increasing frequency in trisomy 13 and 18 patients and concomitantly, survival in this patient population is increasing. Yet across the United States, the willingness to perform cardiac surgery in trisomy 13 and 18 is variable, and there is ethical controversy about the correct action to take. To address this concern, a shared decision-making approach with an informed parent(s) is advised.

SUMMARY

As the care and management of congenital heart disease changed in trisomy 21, so too it has with trisomy 13 and 18. Physicians and parents should develop goal-directed treatment plans balancing the risk versus benefit and consider cardiac surgical repair if feasible and beneficial.

Systems of Care Factors Should Be Considered in Regionalization of Congenital Cardiac Surgery

BACKGROUND

Regionalization of care has been proposed to optimize outcomes in congenital cardiac surgery (CCS). We hypothesized that hospital infrastructure and systems of care factors could also be considered in regionalization efforts.

METHODS

Observed-to-expected (O/E) mortality ratio and hospital volumes were obtained between 2015 and 2018 from public reporting data. Using a resource dependence framework, we examined factors obtained from American Hospital Association, Children's Hospital Association, and hospital websites. Linear regression models were estimated with volume only, then with hospital factors, stratified by procedural complexity. Robust regression models were reestimated to assess the impact of outliers.

RESULTS

We found wide variation in the volume of congenital cardiac surgeries performed (89-3920) and in the surgical outcomes (O/E ratio range, 0.3-3.1). Six outlier hospitals performed few high-complexity cases with high mortality. Univariate analysis including all cases indicated that higher volume predicted lower O/E ratio (β = -0.02; SE = 0.008; P = .011). However, this effect was driven by the most complex cases. Models stratified by The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category show that volume is a significant predictor only in category 5 cases (β = -1.707; SE = 0.663; P = .012). Robust univariate regression accounting for outliers found no effect of volume on O/E ratio (β = 0.005; SE = 0.002; P = .975). Elimination of outliers through robust multivariate regression decreased the volume-outcome relationship and found a modest relationship between health plan ownership and outcomes.

CONCLUSIONS

Systems of care factors should be considered in addition to volume in designing regionalization in CCS. Patient-level data sets will better define these factors.

Operative mortality after Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category 1 to 3 procedures: Deficiencies and opportunities for quality improvement

OBJECTIVES

We examined cases of operative mortality at a single quaternary academic center for patients undergoing relatively lower-risk (Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category 1-3) procedures, as a means of identifying systemic weaknesses and opportunities for quality improvement.

METHODS

A retrospective review of all operative mortality events for patients who underwent a Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category 1, 2, or 3 index procedure (2009-2020) at our institution was performed. After a detailed chart review was performed by 2 independent faculty for each case, factors and system deficiencies that contributed to mortality were identified.

RESULTS

A total of 42 mortalities were identified. A total of 37 patients (88%) had at least 1 Society of Thoracic Surgeons-designated risk factor, including prior cardiac operations (48%), extracardiac malformations (43%), and preoperative ventilation (33%). Eight patients (19%) had non-Society of Thoracic Surgeons-designated preoperative patient-level variables considered as at potential risk, including severe ventricular dysfunction, pulmonary hypertension, lung hypoplasia, and undiagnosed severe coronary abnormalities. Four patients (10%) had no identified preoperative risk factors. After detailed chart review, 5 broad categories were identified: patient-related factors (n = 33; 78%), postoperative infection (n = 13; 31%), postoperative residual lesions (n = 7; 17%), Fontan physiology failure (n = 4; 10%), and unexplained left ventricular failure after tetralogy of Fallot repair (n = 3; 7%). A total of 74% of patients had at least 1 preoperative, intraoperative, or postoperative system deficiency. A total of 50% of surgeries were urgent or emergency.

CONCLUSIONS

Operative mortality after Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category 1 to 3 procedures is related to the presence of multifactorial risk patterns (Society of Thoracic Surgeons and non-Society of Thoracic Surgeons-designated patient-level risk factors and variables, broad risk categories, system deficiencies, emergency surgery). A multidisciplinary approach to care, with early recognition and treatment of modifiable additional burdens, could reduce this risk.

A machine learning approach to predicting 30-day mortality following paediatric cardiac surgery: findings from the Australia New Zealand Congenital Outcomes Registry for Surgery (ANZCORS)

OBJECTIVES

We aim to develop the first risk prediction model for 30-day mortality for the Australian and New Zealand patient populations and examine whether machine learning (ML) algorithms outperform traditional statistical approaches.

METHODS

Data from the Australia New Zealand Congenital Outcomes Registry for Surgery, which contains information on every paediatric cardiac surgical encounter in Australian and New Zealand for patients aged <18 years between January 2013 and December 2021, were analysed (n = 14 343). The outcome was mortality within the 30-day period following a surgical encounter, with ∼30% of the observations randomly selected to be used for validation of the final model. Three different ML methods were used, all of which employed five-fold cross-validation to prevent overfitting, with model performance judged primarily by the area under the receiver operating curve (AUC).

RESULTS

Among the 14 343 30-day periods, there were 188 deaths (1.3%). In the validation data, the gradient-boosted tree obtained the best performance [AUC = 0.87, 95% confidence interval = (0.82, 0.92); calibration = 0.97, 95% confidence interval = (0.72, 1.27)], outperforming penalized logistic regression and artificial neural networks (AUC of 0.82 and 0.81, respectively). The strongest predictors of mortality in the gradient boosting trees were patient weight, STAT score, age and gender.

CONCLUSIONS

Our risk prediction model outperformed logistic regression and achieved a level of discrimination comparable to the PRAiS2 and Society of Thoracic Surgery Congenital Heart Surgery Database mortality risk models (both which obtained AUC = 0.86). Non-linear ML methods can be used to construct accurate clinical risk prediction tools.

Variation in Case-Mix Across Hospitals: Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND

The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database was queried to document variation of patient characteristics, procedure types, and programmatic case-mix.

METHODS

All index cardiac operations in patients less than 18 years of age in the STS Congenital Heart Surgery Database (July 2016 to June 2020) were eligible for inclusion except patients weighing ≤2.5 kg undergoing isolated patent ductus arteriosus closure. At the hospital level, we describe variations in patient and procedural characteristics known from previous analyses to be associated with outcomes. We also report variations across hospitals of programmatic case-mix.

RESULTS

Data were analyzed from 117 sites (90 322 total operations, 87 296 total index cardiac operations eligible for STAT [STS-European Association for Cardio-Thoracic Surgery] 2020 Mortality Score). The median annual total index cardiac operations eligible for STAT 2020 Mortality Score per hospital was 157 (interquartile range [IQR], 94-276). Wide variability was documented in total annual index cardiac operations eligible for STAT 2020 Mortality Score per hospital (ratio 90th/10th percentile = 9.01), operations in neonates weighing <2.5 kg (ratio 90th/10th percentile = 4.09), operations in patients with noncardiac anatomic abnormalities (ratio 90th/10th percentile = 3.46), and operations in patients with preoperative mechanical ventilation (ratio 90th/10th percentile = 3.97). At the hospital level, the median percentage of all index cardiac operations in STAT 2020 Mortality Category 5 was 3.7% (IQR, 1.7%-4.9%), the median percentage of all index cardiac operations in STAT 2020 Mortality Category 4 or 5 was 24.4% (IQR, 19.0%-28.4%), the median hospital-specific mean STAT Mortality Category was 2.39 (IQR, 2.20-2.47), and the median hospital-specific mean STAT Mortality Score was 0.86 (IQR, 0.73-0.91).

CONCLUSIONS

Substantial variation of patient characteristics, procedure types, and case-mix exists across pediatric and congenital cardiac surgical programs. Knowledge about programmatic case-mix augments data about indirectly standardized programmatic observed-to-expected (O/E) mortality. Indirectly standardized O/E ratios do not provide a complete description of a given pediatric and congenital cardiac surgical program. The indirectly standardized programmatic O/E ratios associated with a given program apply only to its specific case-mix of patients and may represent a quite different case-mix than that of another program.

Cardiovascular Complications of Down Syndrome: Scoping Review and Expert Consensus

Cardiovascular disease is a leading cause of morbidity and mortality in individuals with Down syndrome. Congenital heart disease is the most common cardiovascular condition in this group, present in up to 50% of people with Down syndrome and contributing to poor outcomes. Additional factors contributing to cardiovascular outcomes include pulmonary hypertension; coexistent pulmonary, endocrine, and metabolic diseases; and risk factors for atherosclerotic disease. Moreover, disparities in the cardiovascular care of people with Down syndrome compared with the general population, which vary across different geographies and health care systems, further contribute to cardiovascular mortality; this issue is often overlooked by the wider medical community. This review focuses on the diagnosis, prevalence, and management of cardiovascular disease encountered in people with Down syndrome and summarizes available evidence in 10 key areas relating to Down syndrome and cardiac disease, from prenatal diagnosis to disparities in care in areas of differing resource availability. All specialists and nonspecialist clinicians providing care for people with Down syndrome should be aware of best clinical practice in all aspects of care of this distinct population.

Tailored strategy to match anatomy and physiology with intervention can improve outcomes of symptomatic neonates with Ebstein anomaly

OBJECTIVE

Neonatal presentation of Ebstein anomaly (EA) represents the most severe form of this condition. Despite significant advances, operative mortality remains high and management decisions represent a formidable challenge. We used a strategy aimed to match anatomy and physiology with type and time of intervention to increase survival.

METHODS

We performed a review of all patients with fetal or neonatal diagnosis of EA managed at a single center between 2007 and 2020.

RESULTS

Among 18 patients with EA, 8 underwent neonatal intervention. The most common indication included cyanosis and heart failure (8/8), end organ dysfunction (6/8), and maldistribution of cardiac output (6/8). Only 2/8 had antegrade pulmonary blood flow. Associated conditions included pulmonary regurgitation in 4/8, atrial tachyarrhythmia in 4, and a ventricular septal defect in 3. Three patients underwent initial stabilization with main pulmonary artery occlusion including bilateral pulmonary artery banding in 2. Five patients underwent biventricular repair with conversion to right ventricle exclusion in 2 cases. Three others underwent the Starnes procedure as initially planned. The median age at surgery was 10 days (range, 1-30) and median weight 2.6 kg (range, 1.9-4.0). The median duration of mechanical ventilation and intensive care unit stay were 9 days (range, 5-34) and 30 days (range, 15-100), respectively. Operative mortality was 1/8. At a median follow-up of 130 months (range, 5-146), there were no late deaths, and all survivors remain in functional class I and free of valvular reintervention.

CONCLUSIONS

Symptomatic neonates with EA can be effectively managed with good outcomes. Preoperative stabilization and choice of management pathway on the basis of anatomy and physiology can help reduce morbidity and mortality.

Bioethics Forum of Cardiology in the Young. Quo Vadis?

The Editorial Board of Cardiology in the Young has recently discussed the need for a Bioethics Forum and has given authorisation to proceed with its creation. Herein, we provide the organisational structure and launch process to introduce properly this interesting and timely endeavour. By this communication, we are establishing this Bioethics Forum of Cardiology in the Young . We hope to attract manuscripts concerning timely bioethical subjects and to offer the readership the opportunity to respond to these topics with supporting or opposing views as appropriate. New articles regarding timely topics will be written by the readership, as well as by invited authors, and these articles will be published. We hope to stimulate interactive discussion concerning the published manuscripts, and these manuscripts and the associated discussions will be open to all interested parties.

Precision Medicine in Pediatric Cardiology

Precision medicine is a developing strategy for individualized treatment of a wide range of diseases. Congenital heart disease is the most common of all congenital defects and carries a high degree of variability in outcomes because of unidentified causes. Advances have identified individual genetic and environmental factors that have helped understand variations in morbidity and mortality in pediatric cardiology. A focus on genomics and pharmacogenetics has also been key to risk prediction and improvement in drug safety and efficacy in the pediatric population. With the rapidly evolving understanding of these individual factors, there also come challenges in implementation of personalized medicine into our health care model. This review outlines the key features of precision medicine in pediatric cardiology and highlights the clinical effects of these findings in patients with congenital heart disease. [Pediatr Ann. 2022;51(10):e390-e395.].

Considerations for Biventricular Conversion of Fontan Circulation

Despite significant improvements in the management of Fontan circulation in patients with single ventricle physiology, long-term outcomes continue to be suboptimal. Conversion to biventricular circulation is increasingly gaining popularity, particularly in the subset of patients who are not ideal Fontan candidates. Meticulous image-guided planning, extensive preoperative discussions, and a team-based approach are required for successful execution of complex biventricular conversion. A segmental approach to the anatomy of the heart defect allows methodical planning of the technique of biventricular conversion. Ventricular size and function continue to be the Achilles heel of successful biventricular repair. Long-term studies comparing outcomes in patients converted to biventricular circulation to those in patients with Fontan physiology are required to appropriately tailor management approaches to an individual patient.

Diastolic Blood Pressure Alleles Improve Congenital Heart Defect Repair Outcomes

BACKGROUND

Congenital heart defects (CHDs) affect 40 000 US births per year, half of which require surgical intervention. Individual differences in surgical outcomes including mortality and complications are not well understood but may be due to genetic variability. We hypothesized that polygenic risk scores (PRSs) for blood pressure in adults are associated with treatments and postsurgical outcomes in children with CHD, as CHD survivors are at higher risk of negative cardiometabolic disease.

METHODS

We used imputed genotype data from pediatric participants requiring surgery for CHD (median age at surgery, 201 days; n_max=2498). Base data for the systolic and diastolic blood pressure PRSs (n_max=760 226) came from published genome-wide association study. The blood pressure PRSs were tested for association with postsurgical outcomes. All effects presented are per SD increase in PRS and adjusted for age, sex, body mass index, surgical complexity score, and first 10 principal components of ancestry.

RESULTS

A higher diastolic blood pressure PRS was associated with decreased in-hospital mortality risk (odds ratio, 0.57 [0.39-0.82]; P=0.0022). Additional analyses suggest an interaction between diastolic blood pressure PRS and vasopressor dose. Those with a diastolic blood pressure PRS 1 SD above the mean, receiving a vasopressor dose in the top tertile, were estimated to have 52% (32%-66%) lower risk of in-hospital mortality compared with those with a vasopressor dose in the bottom tertile.

CONCLUSIONS

These results suggest a genetically determined postsurgical survival advantage for CHD patients with blood pressure increasing alleles. Further study may reveal novel mechanisms contributing to postoperative morbidity and mortality, and this approach may assist in early identification of children at risk for adverse postoperative outcomes.

Risk Stratification for Congenital Heart Surgery for ICD-10 Administrative Data (RACHS-2)

BACKGROUND

As the cardiac community strives to improve outcomes, accurate methods of risk stratification are imperative. Since adoption of International Classification of Disease-10th Revision (ICD-10) in 2015, there is no published method for congenital heart surgery risk stratification for administrative data.

OBJECTIVES

This study sought to develop an empirically derived, publicly available Risk Stratification for Congenital Heart Surgery (RACHS-2) tool for ICD-10 administrative data.

METHODS

The RACHS-2 stratification system was iteratively and empirically refined in a training dataset of Pediatric Health Information Systems claims to optimize sensitivity and specificity compared with corresponding locally held Society of Thoracic Surgeons-Congenital Heart Surgery (STS-CHS) clinical registry data. The tool was validated in a second administrative data source: New York State Medicaid claims. Logistic regression was used to compare the ability of RACHS-2 in administrative data to predict operative mortality vs STAT Mortality Categories in registry data.

RESULTS

The RACHS-2 system captured 99.6% of total congenital heart surgery registry cases, with 1.0% false positives. RACHS-2 predicted operative mortality in both training and validation administrative datasets similarly to STAT Mortality Categories in registry data. C-statistics for models for operative mortality in training and validation administrative datasets-adjusted for RACHS-2-were 0.76 and 0.84 (95% CI: 0.72-0.80 and 0.80-0.89); C-statistics for models for operative mortality-adjusted for STAT Mortality Categories-in corresponding clinical registry data were 0.75 and 0.84 (95% CI: 0.71-0.79 and 0.79-0.89).

CONCLUSIONS

RACHS-2 is a risk stratification system for pediatric cardiac surgery for ICD-10 administrative data, validated in 2 administrative-registry-linked datasets. Statistical code is publicly available upon request.

Mortality Prediction Following Cardiac Surgery in Children - An STS Congenital Heart Surgery Database Analysis

BACKGROUND

The Society of Thoracic Surgeons' Congenital Heart Surgery Database (STS CHSD) provides risk-adjusted operative mortality rates to approximately 120 North American congenital heart centers. Optimal case-mix adjustment methods for operative mortality risk prediction in this population remain unclear.

METHODS

A panel created diagnosis-procedure (D-P) combinations of encounters in the CHSD. Models for operative mortality using the new D-P categories, procedure-specific risk factors, and syndromes/abnormalities included in the CHSD were estimated using Bayesian additive regression trees (BART) and lasso models. Performance of the new models was compared to the current STS-CHSD risk model.

RESULTS

Of 98,825 operative encounters (69,063 training; 29,762 testing), 2,818 (2.85%) STS-defined operative mortalities were observed. Differences in sensitivity, specificity, true and false positive predicted values were negligible across models. Calibration for mortality predictions at the higher end of risk from the lasso and BART models was better than predictions from the STS-CHSD model, likely due to new models' inclusion of diagnosis-palliative procedure variables affecting < 1% of patients overall, but accounting for 27% of mortalities. Model discrimination varied across models for high-risk procedures, hospital volume, and hospitals.

CONCLUSIONS

Overall performance of the new models did not differ meaningfully from the STS-CHSD risk model. Addition of procedure-specific risk factors and allowing diagnosis to modify predicted risk for palliative operations may augment model performance for very high-risk surgeries. Given the importance of risk adjustment in estimating hospital quality, a comparative assessment of surgical program quality evaluations using the different models is warranted.

Re-evaluating Congenital Heart Surgery Center Performance Using Operative Mortality

BACKGROUND

The Society of Thoracic Surgeons' Congenital Heart Surgery Database provides observed to expected (O/E) operative mortality ratios to more than 100 congenital heart centers in North America. We compared the current approach (STS-CHSD) for estimating O/E ratios to approaches incorporating information on diagnosis as moderators of procedures, other unutilized risk factors, and additional variation in confidence interval (CI) construction to characterize center performance.

METHODS

Bayesian additive regression trees (BART) and lasso models linked operative mortality to diagnosis-procedure categories, procedure-specific risk factors, and syndromes/abnormalities. Bootstrapping accounted for variation in STS-CHSD (STS Bootstrap) and lasso CIs. We compared O/E estimates, interquartile range (IQR) of CI widths, and concordance of center performance categorizations (worse-than-, as-, or better-than-expected mortality) of the new approaches to the STS-CHSD.

RESULTS

In 110 surgical centers including 98,822 surgical operative encounters, there were 2818 (2.85%) operative mortalities (center range: 0.37% to 10%). Compared to the STS-CHSD, BART and lasso estimated O/E ratios varied more and had narrower CIs (IQR of CI: STS-CHSD = 1.11, STS Bootstrap = 0.98; lasso = 0.80; BART = 0.96). Concordance of performance categorization with the STS-CHSD ranged from 84% (lasso) to 91% (STS Bootstrap); more than 70% of discordant centers improved categories. Discordant centers had smaller volumes, fewer operative mortalities, and treated more patients with congenital lung abnormalities.

CONCLUSIONS

Relative to the STS-CHSD, up to 16% of hospitals changed performance categories, most improving performance. Given the significance of quality reports for congenital heart centers, inclusion of additional risk factors and unaddressed variation should be considered.

Comparison of Postoperative, In-Hospital Outcomes After Complete Repair of Tetralogy of Fallot Between 22q11.2 Deletion Syndrome and Trisomy 21

22q11.2 deletion syndrome (22q11) and trisomy 21 (T21) are frequently associated with tetralogy of Fallot (TOF). We hypothesized that there are differences in postoperative length of stay (LOS) and occurrence of postoperative interventions after complete repair of TOF when comparing children with 22q11 to those with T21. Using the Pediatric Health Information System, we performed a retrospective cohort study of patients who underwent complete repair of TOF from 2004 to 2019. Three groups were identified: 22q11, T21, and controls (those without a coded genetic syndrome). Outcomes were postoperative LOS and composite occurrence (yes/no) of at least one postoperative intervention. Bivariate and multivariate comparisons were made among groups; odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the control group as the comparator. There were 6924 subjects (n = 493 22q11, n = 455 T21, n = 5976 controls). In bivariate analysis, 22q11 was associated with a longer LOS compared to T21 (OR 2.37 [2.16, 2.60] vs. 1.25 [1.12, 1.39], p < 0.001), and 22q11 more often underwent postoperative intervention (OR 3.42 [CI 2.56, 4.57] vs. 1.38 [CI 0.91, 2.11]; p < 0.001). In multivariate analysis, 22q11 was also associated with longer LOS (adjusted OR 1.35 [1.26, 1.44] vs. 1.12 [1.04, 1.20]; p < 0.001), but there was no difference in the adjusted odds of postoperative intervention. Children with 22q11 are more likely to experience adverse outcomes after repair of TOF compared to those with T21; the differences are most pronounced for LOS.

Are outcomes in congenital cardiac surgery better than ever?

BACKGROUND AND AIM OF THE STUDY

Congenital heart disease is the most common congenital defect among infants born in the United States. Within the first year of life, 1 in 4 of these infants will need surgery. Only one generation removed from an overall mortality of 14%, many changes have been introduced into the field. Have these changes measurably improved outcomes?

METHODS

The literature search was conducted through PubMed MEDLINE and Google Scholar from inception to October 31, 2021. Ultimately, 78 publications were chosen for inclusion.

RESULTS

The outcome of overall mortality has experienced continuous improvements in the modern era of the specialty despite the performance of more technically demanding surgeries on patients with complex comorbidities. This modality does not account for case-mix, however. In turn, clinical outcomes have not been consistent from center to center. Furthermore, variation in practice between institutions has also been documented. A recurring theme in the literature is a movement toward standardization and universalization. Examples include mortality risk-stratification that has allowed direct comparison of outcomes between programs and improved definitions of morbidities which provide an enhanced framework for diagnosis and management.

CONCLUSIONS

Overall mortality is now below 3%, which suggests that more patients are surviving their interventions than in any previous era in congenital cardiac surgery. Focus has transitioned from survival to improving the quality of life in the survivors by decreasing the incidence of morbidity and associated long-term effects. With the transformation toward standardization and interinstitutional collaboration, future advancements are expected.

Benchmarking in Congenital Heart Surgery Using Machine Learning-Derived Optimal Classification Trees

Background: We have previously shown that the machine learning methodology of optimal classification trees (OCTs) can accurately predict risk after congenital heart surgery (CHS). We have now applied this methodology to define benchmarking standards after CHS, permitting case-adjusted hospital-specific performance evaluation. Methods: The European Congenital Heart Surgeons Association Congenital Database data subset (31 792 patients) who had undergone any of the 10 "benchmark procedure group" primary procedures were analyzed. OCT models were built predicting hospital mortality (HM), and prolonged postoperative mechanical ventilatory support time (MVST) or length of hospital stay (LOS), thereby establishing case-adjusted benchmarking standards reflecting the overall performance of all participating hospitals, designated as the "virtual hospital." These models were then used to predict individual hospitals' expected outcomes (both aggregate and, importantly, for risk-matched patient cohorts) for their own specific cases and case-mix, based on OCT analysis of aggregate data from the "virtual hospital." Results: The raw average rates were HM = 4.4%, MVST = 15.3%, and LOS = 15.5%. Of 64 participating centers, in comparison with each hospital's specific case-adjusted benchmark, 17.0% statistically (under 90% confidence intervals) overperformed and 26.4% underperformed with respect to the predicted outcomes for their own specific cases and case-mix. For MVST and LOS, overperformers were 34.0% and 26.4%, and underperformers were 28.3% and 43.4%, respectively. OCT analyses reveal hospital-specific patient cohorts of either overperformance or underperformance. Conclusions: OCT benchmarking analysis can assess hospital-specific case-adjusted performance after CHS, both overall and patient cohort-specific, serving as a tool for hospital self-assessment and quality improvement.

Nomenclature for Pediatric and Congenital Cardiac Care: Unification of Clinical and Administrative Nomenclature - The 2021 International Paediatric and Congenital Cardiac Code (IPCCC) and the Eleventh Revision of the International Classification of Diseases (ICD-11)

Substantial progress has been made in the standardization of nomenclature for paediatric and congenital cardiac care. In 1936, Maude Abbott published her Atlas of Congenital Cardiac Disease, which was the first formal attempt to classify congenital heart disease. The International Paediatric and Congenital Cardiac Code (IPCCC) is now utilized worldwide and has most recently become the paediatric and congenital cardiac component of the Eleventh Revision of the International Classification of Diseases (ICD-11). The most recent publication of the IPCCC was in 2017. This manuscript provides an updated 2021 version of the IPCCC. The International Society for Nomenclature of Paediatric and Congenital Heart Disease (ISNPCHD), in collaboration with the World Health Organization (WHO), developed the paediatric and congenital cardiac nomenclature that is now within the eleventh version of the International Classification of Diseases (ICD-11). This unification of IPCCC and ICD-11 is the IPCCC ICD-11 Nomenclature and is the first time that the clinical nomenclature for paediatric and congenital cardiac care and the administrative nomenclature for paediatric and congenital cardiac care are harmonized. The resultant congenital cardiac component of ICD-11 was increased from 29 congenital cardiac codes in ICD-9 and 73 congenital cardiac codes in ICD-10 to 318 codes submitted by ISNPCHD through 2018 for incorporation into ICD-11. After these 318 terms were incorporated into ICD-11 in 2018, the WHO ICD-11 team added an additional 49 terms, some of which are acceptable legacy terms from ICD-10, while others provide greater granularity than the ISNPCHD thought was originally acceptable. Thus, the total number of paediatric and congenital cardiac terms in ICD-11 is 367. In this manuscript, we describe and review the terminology, hierarchy, and definitions of the IPCCC ICD-11 Nomenclature. This article, therefore, presents a global system of nomenclature for paediatric and congenital cardiac care that unifies clinical and administrative nomenclature.The members of ISNPCHD realize that the nomenclature published in this manuscript will continue to evolve. The version of the IPCCC that was published in 2017 has evolved and changed, and it is now replaced by this 2021 version. In the future, ISNPCHD will again publish updated versions of IPCCC, as IPCCC continues to evolve.

Does It Measure Up?

Measuring outcomes in pediatric cardiac care has been one of the more widespread, and at the same time controversial and often polarizing, quality improvement initiatives undertaken in the medical field. Risk models, such as the Society of Thoracic Surgeons Congenital Heart Surgery Risk Model, have been developed to account for comorbidities while predicting the expected mortality for a given surgical encounter. In this issue of the journal, Bertsimas and colleagues report on machine learning approaches to predict adverse outcomes in congenital heart surgery using the European Congenital Heart Surgeons Association's congenital database. A head-to-head comparison of machine learning models and the currently available risk models utilizing the same data set are required to better understand the strengths and weaknesses of each of these approaches. Such a focused analysis will shed light on future approaches for risk modeling, which will undoubtedly continue to benefit from the guidance provided by expert clinical intuition.

Nomenclature for Pediatric and Congenital Cardiac Care: Unification of Clinical and Administrative Nomenclature - The 2021 International Paediatric and Congenital Cardiac Code (IPCCC) and the Eleventh Revision of the International Classification of Diseases (ICD-11)

Substantial progress has been made in the standardization of nomenclature for paediatric and congenital cardiac care. In 1936, Maude Abbott published her Atlas of Congenital Cardiac Disease, which was the first formal attempt to classify congenital heart disease. The International Paediatric and Congenital Cardiac Code (IPCCC) is now utilized worldwide and has most recently become the paediatric and congenital cardiac component of the Eleventh Revision of the International Classification of Diseases (ICD-11). The most recent publication of the IPCCC was in 2017. This manuscript provides an updated 2021 version of the IPCCC.The International Society for Nomenclature of Paediatric and Congenital Heart Disease (ISNPCHD), in collaboration with the World Health Organization (WHO), developed the paediatric and congenital cardiac nomenclature that is now within the eleventh version of the International Classification of Diseases (ICD-11). This unification of IPCCC and ICD-11 is the IPCCC ICD-11 Nomenclature and is the first time that the clinical nomenclature for paediatric and congenital cardiac care and the administrative nomenclature for paediatric and congenital cardiac care are harmonized. The resultant congenital cardiac component of ICD-11 was increased from 29 congenital cardiac codes in ICD-9 and 73 congenital cardiac codes in ICD-10 to 318 codes submitted by ISNPCHD through 2018 for incorporation into ICD-11. After these 318 terms were incorporated into ICD-11 in 2018, the WHO ICD-11 team added an additional 49 terms, some of which are acceptable legacy terms from ICD-10, while others provide greater granularity than the ISNPCHD thought was originally acceptable. Thus, the total number of paediatric and congenital cardiac terms in ICD-11 is 367. In this manuscript, we describe and review the terminology, hierarchy, and definitions of the IPCCC ICD-11 Nomenclature. This article, therefore, presents a global system of nomenclature for paediatric and congenital cardiac care that unifies clinical and administrative nomenclature.The members of ISNPCHD realize that the nomenclature published in this manuscript will continue to evolve. The version of the IPCCC that was published in 2017 has evolved and changed, and it is now replaced by this 2021 version. In the future, ISNPCHD will again publish updated versions of IPCCC, as IPCCC continues to evolve.

Evolving Cost-Quality Relationship in Pediatric Heart Surgery

BACKGROUND

For the >40,000 US children undergoing congenital heart surgery annually, the relationship between hospital quality and costs remains unclear. Prior studies report conflicting results and clinical outcomes have continued to improve over time. We examined a large contemporary cohort, aiming to better inform ongoing initiatives seeking to optimize healthcare value in this population.

METHODS

Clinical information (Society of Thoracic Surgeons Congenital Database) was merged with standardized cost data (Pediatric Health Information Systems) for children undergoing heart surgery from 2010-2015. In-hospital cost variability was analyzed using Bayesian hierarchical models adjusted for case-mix. Quality metrics examined included in-hospital mortality, post-operative complications, length of stay (PLOS), and a composite.

RESULTS

Overall 32 hospitals (n=45,315 patients) were included. Median adjusted cost/case varied across hospitals from $67,700 to $51,200 in the high vs. low cost tertile (ratio 1.32, 95% credible interval 1.29-1.35), and all quality metrics also varied across hospitals. Across cost tertiles there were no significant differences in the quality metrics examined, with the exception of PLOS. The PLOS findings were driven by high-risk STAT 4-5 cases [adjusted median LOS 16.8 vs. 14.9 days in high vs. low cost tertile (ratio 1.13, 1.05-1.24)], and ICU PLOS.

CONCLUSIONS

Contemporary congenital heart surgery costs vary across hospitals but were not associated with most quality metrics examined, highlighting that performance in one area does not necessarily convey to others. Cost variability was associated with PLOS, particularly related to ICU PLOS and high-risk cases. Care processes influencing PLOS may provide targets for value-based initiatives in this population.

Risk evaluation in adult congenital heart surgery: analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database risk models on data from the European Congenital Heart Surgeons Association Congenital Database

 

OBJECTIVES

We sought to evaluate the predictive power of the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) mortality score and the adult congenital heart surgery (ACHS) mortality score for the adults undergoing congenital heart operations entered into the European Congenital Heart Surgeons Association (ECHSA) database.

METHODS

The data set comprised 17 662 major operations performed between 1997 and 2019, on patients 18 years of age or older, in European centres participating in the ECHSA database. Each operation was assigned a STAT mortality score and category and an ACHS mortality score. Operative mortality was based on the 30-day status and on the status at hospital discharge. The discriminatory power of the STAT and ACHS scores was assessed using the area under the receiver operating characteristic curve (c-index).

RESULTS

A total of 17 214 (97.46%) operations were assigned ACHS scores. The 3 most frequent primary procedures were closure of the atrial septal defect (19.0%), aortic valve replacement (8.8%) and non-valve-sparing aortic root replacement (6.1%). Operative mortality for ACHS-coded operations was 2.07%. The procedures with the highest mortality were atrial septal defect creation/enlargement (19.0%), lung transplantation (18.8%) and heart transplantation (18.2%). A total of 17 638 (99.86%) operations were assigned a STAT score and category. The operative mortality for STAT-coded operations was 2.27%. The c-index for mortality was 0.720 for the STAT mortality score and 0.701 for the ACHS score.

CONCLUSIONS

The ACHS mortality score and the STAT mortality score reached similar, moderate predictive power in adult patients undergoing congenital heart surgery in ECHSA database.

Adverse Outcomes Prediction for Congenital Heart Surgery: A Machine Learning Approach

OBJECTIVE

Risk assessment tools typically used in congenital heart surgery (CHS) assume that various possible risk factors interact in a linear and additive fashion, an assumption that may not reflect reality. Using artificial intelligence techniques, we sought to develop nonlinear models for predicting outcomes in CHS.

METHODS

We built machine learning (ML) models to predict mortality, postoperative mechanical ventilatory support time (MVST), and hospital length of stay (LOS) for patients who underwent CHS, based on data of more than 235,000 patients and 295,000 operations provided by the European Congenital Heart Surgeons Association Congenital Database. We used optimal classification trees (OCTs) methodology for its interpretability and accuracy, and compared to logistic regression and state-of-the-art ML methods (Random Forests, Gradient Boosting), reporting their area under the curve (AUC or c-statistic) for both training and testing data sets.

RESULTS

Optimal classification trees achieve outstanding performance across all three models (mortality AUC = 0.86, prolonged MVST AUC = 0.85, prolonged LOS AUC = 0.82), while being intuitively interpretable. The most significant predictors of mortality are procedure, age, and weight, followed by days since previous admission and any general preoperative patient risk factors.

CONCLUSIONS

The nonlinear ML-based models of OCTs are intuitively interpretable and provide superior predictive power. The associated risk calculator allows easy, accurate, and understandable estimation of individual patient risks, in the theoretical framework of the average performance of all centers represented in the database. This methodology has the potential to facilitate decision-making and resource optimization in CHS, enabling total quality management and precise benchmarking initiatives.

Updating an Empirically Based Tool for Analyzing Congenital Heart Surgery Mortality

OBJECTIVES

STAT Mortality Categories (developed 2009) stratify congenital heart surgery procedures into groups of increasing mortality risk to characterize case mix of congenital heart surgery providers. This update of the STAT Mortality Score and Categories is empirically based for all procedures and reflects contemporary outcomes.

METHODS

Cardiovascular surgical operations in the Society of Thoracic Surgeons Congenital Heart Surgery Database (January 1, 2010 - June 30, 2017) were analyzed. In this STAT 2020 Update of the STAT Mortality Score and Categories, the risk associated with a specific combination of procedures was estimated under the assumption that risk is determined by the highest risk individual component procedure. Operations composed of multiple component procedures were eligible for unique STAT Scores when the statistically estimated mortality risk differed from that of the highest risk component procedure. Bayesian modeling accounted for small denominators. Risk estimates were rescaled to STAT 2020 Scores between 0.1 and 5.0. STAT 2020 Category assignment was designed to minimize within-category variation and maximize between-category variation.

RESULTS

Among 161,351 operations at 110 centers (19,090 distinct procedure combinations), 235 types of single or multiple component operations received unique STAT 2020 Scores. Assignment to Categories resulted in the following distribution: STAT 2020 Category 1 includes 59 procedure codes with model-based estimated mortality 0.2% to 1.3%; Category 2 includes 73 procedure codes with mortality estimates 1.4% to 2.9%; Category 3 includes 46 procedure codes with mortality estimates 3.0% to 6.8%; Category 4 includes 37 procedure codes with mortality estimates 6.9% to 13.0%; and Category 5 includes 17 procedure codes with mortality estimates 13.5% to 38.7%. The number of procedure codes with empirically derived Scores has grown by 58% (235 in STAT 2020 vs 148 in STAT 2009). Of the 148 procedure codes with empirically derived Scores in 2009, approximately one-half have changed STAT Category relative to 2009 metrics. The New STAT 2020 Scores and Categories demonstrated good discrimination for predicting mortality in an independent validation sample (July 1, 2017-June 30, 2019; sample size 46,933 operations at 108 centers) with C-statistic = 0.791 for STAT 2020 Score and 0.779 for STAT 2020 Category.

CONCLUSIONS

The updated STAT metrics reflect contemporary practice and outcomes. New empirically based STAT 2020 Scores and Category designations are assigned to a larger set of procedure codes, while accounting for risk associated with multiple component operations. Updating STAT metrics based on contemporary outcomes facilitates accurate assessment of case mix.

Clinical Importance of Concomitant Cleft Lip/Palate in the Surgical Management of Patients With Congenital Heart Disease

BACKGROUND

Congenital heart disease (CHD) frequently occurs in conjunction with extracardiac developmental anomalies, including cleft malformations. The clinical impact of concomitant cleft disease on the surgical management of CHD has not been studied. We evaluated cardiac surgical outcomes in patients with concomitant CHD and cleft lip and/or palate (CL/P).

METHODS

Patients with CHD + CL/P managed at our institution between January 2004 and December 2018 were included. Demographic, operative, and follow-up data were retrospectively collected and analyzed using SAS 9.4. Chi-square tests were used for categorical variables and t test or Wilcoxon rank sum tests for continuous variables. Significance of P < .05 was used.

RESULTS

There were 127 patients with CHD + CL/P; 63 (50%) were boys. Compared to the general CHD population, patients with CHD + CL/P demonstrated an enrichment of atrial septal defects (10.5% vs 34%), tetralogy of Fallot/double outlet right ventricle (6.4% vs 15.7%), arch defects (4.5% vs 10.2%), truncus arteriosus (1.2% vs 3.1%), and total anomalous pulmonary venous return (1.0% vs 2.4%). Of 63 patients who underwent CHD repair, 58 (92%) did so prior to CL/P repair at 21.5 (6-114) days of age. Compared to CHD lesion-matched patients undergoing cardiac surgical repair at our institution, patients with CL/P had a 2- to 3.7-fold longer intensive care stay, 1.8- to 2.6-fold longer hospital stay, and 6- to 13.5-fold increase in major morbidity, without a significant difference in mortality.

CONCLUSIONS

Cardiac outflow tract defects are particularly overrepresented in CL/P patients. The presence of CL/P increases the complexity of postoperative care after CHD surgery, without a significant impact on mortality.

Postoperative Hematocrit and Adverse Outcomes in Pediatric Cardiac Surgery Patients: A Cross-Sectional Study From the Society of Thoracic Surgeons and Congenital Cardiac Anesthesia Society Database Collaboration

BACKGROUND

We sought to examine potential associations between pediatric postcardiac surgical hematocrit values and postoperative complications or mortality.

METHODS

A retrospective, cross-sectional study from the Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) and Congenital Cardiac Anesthesia Society Database Module (2014-2019) was completed. Multivariable logistic regression models, adjusting for covariates in the STS-CHSD mortality risk model, were used to assess the relationship between postoperative hematocrit and the primary outcomes of operative mortality or any major complication. Hematocrit was assessed as a continuous variable using linear splines to account for nonlinear relationships with outcomes. Operations after which the oxygen saturation is typically observed to be <92% were classified as cyanotic and ≥92% as acyanotic.

RESULTS

In total, 27,462 index operations were included, with 4909 (17.9%) being cyanotic and 22,553 (82.1%) acyanotic. For cyanotic patients, each 5% incremental increase in hematocrit over 42% was associated with a 1.31-fold (95% confidence interval [CI], 1.10-1.55; P = .003) increase in the odds of operative mortality and a 1.22-fold (95% CI, 1.10-1.36; P < .001) increase in the odds of a major complication. For acyanotic patients, each 5% incremental increase in hematocrit >38% was associated with a 1.45-fold (95% CI, 1.28-1.65; P < .001) increase in the odds of operative mortality and a 1.21-fold (95% CI, 1.14-1.29; P < .001) increase in the odds of a major complication.

CONCLUSIONS

High hematocrit on arrival to the intensive care unit (ICU) is associated with increased operative mortality and major complications in pediatric patients following cardiac surgery.

Variants of significance: medical genetics and surgical outcomes in congenital heart disease

PURPOSE OF REVIEW

This article reviews the current understanding and limitations in knowledge of the effect genetics and genetic diagnoses have on perioperative and postoperative surgical outcomes in patients with congenital heart disease (CHD).

RECENT FINDINGS

Presence of a known genetic diagnosis seems to effect multiple significant outcome metrics in CHD surgery including length of stay, need for extracorporeal membrane oxygenation, mortality, bleeding, and heart failure. Data regarding the effects of genetics in CHD is complicated by lack of standard genetic assessment resulting in inaccurate risk stratification of patients when analyzing data. Only 30% of variation in CHD surgical outcomes are explained by currently measured variables, with 2.5% being attributed to diagnosed genetic disorders, it is thought a significant amount of the remaining outcome variation is because of unmeasured genetic factors.

SUMMARY

Genetic diagnoses clearly have a significant effect on surgical outcomes in patients with CHD. Our current understanding is limited by lack of consistent genetic evaluation and assessment as well as evolving knowledge and discovery regarding the genetics of CHD. Standardizing genetic assessment of patients with CHD will allow for the best risk stratification and ultimate understanding of these effects.

External validation of the improving partial risk adjustment in surgery (PRAIS-2) model for 30-day mortality after paediatric cardiac surgery

OBJECTIVE

Independent temporal external validation of the improving partial risk adjustment in surgery model (PRAIS-2) to predict 30-day mortality in patients undergoing paediatric cardiac surgery.

DESIGN

Retrospective analysis of prospectively collected data.

SETTING

Paediatric cardiac surgery.

INTERVENTION

PRAIS-2 validation was carried out using a two temporally different single centre (Bristol, UK) cohorts: Cohort 1 surgery undertaken from April 2004 to March 2009 and Cohort 2 from April 2015 to July 2019. For each subject PRAIS-2 score was calculated according to the original formula.

PARTICIPANTS

A total of 1352 (2004-2009) and 1197 (2015-2019) paediatric cardiac surgical procedures were included in the Cohort 1 and Cohort 2, respectively (median age at the procedure 6.3 and 7.1 months).

PRIMARY AND SECONDARY OUTCOME MEASURES

PRAIS-2 performance was assessed in terms of discrimination by means of ROC (receiver operating characteristic) curve analysis and calibration by using the calibration belt method.

RESULTS

PRAIS-2 score showed excellent discrimination for both cohorts (AUC 0.72 (95%CI: 0.65 to 0.80) and 0.88 (95%CI: 0.82 to 0.93), respectively). While PRAIS-2 was only marginally calibrated in Cohort 1, with a tendency to underestimate risk in lowrisk and overestimate risk in high risk procedures (P-value = 0.033), validation in Cohort 2 showed good calibration with the 95% confidence belt containing the bisector for predicted mortality (P-value = 0.143). We also observed good prediction accuracy in the non-elective procedures (N = 483;AUC 0.78 (95%CI 0.68 to 0.87); Calibration belt containing the bisector (P-value=0.589).

CONCLUSIONS

In a single centre UK-based cohort, PRAIS-2 showed excellent discrimination and calibration in predicting 30-day mortality in paediatric cardiac surgery including in those undergoing non-elective procedures. Our results support a wider adoption of PRAIS-2 score in the clinical practice.

Tracheal surgery for airway anomalies associated with increased mortality in pediatric patients undergoing heart surgery: Society of Thoracic Surgeons Database analysis

OBJECTIVES

Airway anomalies are common in children with cardiac disease but with an unquantified impact on outcomes. We sought to define the association between airway anomalies and tracheal surgery with cardiac surgery outcomes using the Society of Thoracic Surgery Congenital Heart Surgery Database.

METHODS

Index cardiac operations in children aged less than 18 years (January 2010 to September 2018) were identified from the Society of Thoracic Surgery Congenital Heart Surgery Database. Patients were divided on the basis of reported diagnosis of an airway anomaly and subdivided on the basis of tracheal lesion and tracheal surgery. Multivariable analysis evaluated associations between airway disease and outcomes controlling for covariates from the Society of Thoracic Surgery Congenital Heart Surgery Database Mortality Risk Model.

RESULTS

Of 198,674 index cardiovascular operations, 6861 (3.4%) were performed in patients with airway anomalies, including 428 patients (0.2%) who also underwent tracheal operations during the same hospitalization. Patients with airway anomalies underwent more complex cardiac operations (45% vs 36% Society of Thoracic Surgeons/European Association for Cardiothoracic Surgery Congenital Heart Surgery Mortality category ≥3 procedures) and had a higher prevalence of preoperative risk factors (73% vs 39%; both P < .001). In multivariable analysis, patients with airway anomalies had increased odds of major morbidity and tracheostomy (P < .001). Operative mortality was also increased in patients with airway anomalies, except those with malacia. Tracheal surgery within the same hospitalization increased the odds of operative mortality (adjusted odds ratio, 3.9; P < .0001), major morbidity (adjusted odds ratio, 3.7; P < .0001), and tracheostomy (adjusted odds ratio, 16.7; P < .0001).

CONCLUSIONS

Patients undergoing cardiac surgery and tracheal surgery are at significantly higher risk of morbidity and mortality than patients receiving cardiac surgery alone. Most of those with unoperated airway anomalies have higher morbidity and mortality, which makes it an important preoperative consideration.

Trisomy 21 Patients Undergoing Cavopulmonary Connections Need Improved Preoperative and Postoperative Care

BACKGROUND

Patients with trisomy 21 (T21) often have elevated pulmonary vascular resistance, which may result in a suboptimal cavopulmonary connection (CPC) after a Glenn or Fontan operation. The purpose of this study was to assess, in a nationwide, multiinstitution cohort of patients with CPC, the impact of T21 on patient morbidity, mortality, and resource use.

METHODS

A total of 23,271 pediatric patients with CPC (2004 to 2019) at 50 US hospitals were evaluated using the Pediatric Health Information System database. Univariable and multivariable regression analyses were used to assess risk-adjusted associations between Down syndrome and other risk factors and postoperative measures of morbidity, mortality, lengths of stay, and cost of hospitalization.

RESULTS

The overall prevalence of T21 among patients who had undergone Glenn and Fontan procedures was 1.5% (199 of 13,268) and 0.8% (78 of 1003), respectively. Among both CPC cohorts, T21 status significantly increased unadjusted mortality, hospital lengths of stay, and total costs of hospitalization compared with the non-T21 CPC cohort (all P < .001). Patients with T21 also had a higher incidence of prolonged mechanical ventilation compared with patients without T21 in both Glenn and Fontan groups (P < .001). Multivariable regression analysis further estimated that patients with T21 are associated with a 5.5-fold increase in mortality (P < .001) compared with patients without T21. Finally, patients with T21 had increased long-term mortality compared with their peers.

CONCLUSIONS

T21 significantly increases risk-adjusted morbidity, inpatient mortality, long-term mortality, and resource use after cavopulmonary connections. Further investigation is needed to clarify modifiable patient-level and center-specific risk factors to improve outcomes for patients with T21.

National Variation in Congenital Heart Surgery Outcomes

BACKGROUND

Optimal strategies to improve national congenital heart surgery outcomes and reduce variability across hospitals remain unclear. Many policy and quality improvement efforts have focused primarily on higher-risk patients and mortality alone. Improving our understanding of both morbidity and mortality and current variation across the spectrum of complexity would better inform future efforts.

METHODS

Hospitals participating in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2014-2017) were included. Case mix-adjusted operative mortality, major complications, and postoperative length of stay were evaluated using Bayesian models. Hospital variation was quantified by the interdecile ratio (IDR, upper versus lower 10%) and 95% credible intervals (CrIs). Stratified analyses were performed by risk group (Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery [STAT] category) and simulations evaluated the potential impact of reductions in variation.

RESULTS

A total of 102 hospitals (n=84 407) were included, representing ≈85% of US congenital heart programs. STAT category 1 to 3 (lower risk) operations comprised 74% of cases. All outcomes varied significantly across hospitals: adjusted mortality by 3-fold (upper versus lower decile 5.0% versus 1.6%, IDR 3.1 [95% CrI 2.5-3.7]), mean length of stay by 1.8-fold (19.2 versus 10.5 days, IDR 1.8 [95% CrI 1.8-1.9]), and major complications by >3-fold (23.5% versus 7.0%, IDR 3.4 [95% CrI 3.0-3.8]). The degree of variation was similar or greater for low- versus high-risk cases across outcomes, eg, ≈3-fold mortality variation across hospitals for STAT 1 to 3 (IDR 3.0 [95% CrI 2.1-4.2]) and STAT 4 or 5 (IDR 3.1 [95% CrI 2.4-3.9]) cases. High-volume hospitals had less variability across outcomes and risk categories. Simulations suggested potential reductions in deaths (n=282), major complications (n=1539), and length of stay (101 183 days) over the 4-year study period if all hospitals were to perform at the current median or better, with 37% to 60% of the improvement related to the STAT 1 to 3 (lower risk) group across outcomes.

CONCLUSIONS

We demonstrate significant hospital variation in morbidity and mortality after congenital heart surgery. Contrary to traditional thinking, a substantial portion of potential improvements that could be realized on a national scale were related to variability among lower-risk cases. These findings suggest modifications to our current approaches to optimize care and outcomes in this population are needed.

Improving preoperative risk-of-death prediction in surgery congenital heart defects using artificial intelligence model: A pilot study

Background

Congenital heart disease accounts for almost a third of all major congenital anomalies. Congenital heart defects have a significant impact on morbidity, mortality and health costs for children and adults. Research regarding the risk of pre-surgical mortality is scarce.

Objectives

Our goal is to generate a predictive model calculator adapted to the regional reality focused on individual mortality prediction among patients with congenital heart disease undergoing cardiac surgery.

Methods

Two thousand two hundred forty CHD consecutive patients’ data from InCor’s heart surgery program was used to develop and validate the preoperative risk-of-death prediction model of congenital patients undergoing heart surgery. There were six artificial intelligence models most cited in medical references used in this study: Multilayer Perceptron (MLP), Random Forest (RF), Extra Trees (ET), Stochastic Gradient Boosting (SGB), Ada Boost Classification (ABC) and Bag Decision Trees (BDT).

Results

The top performing areas under the curve were achieved using Random Forest (0.902). Most influential predictors included previous admission to ICU, diagnostic group, patient's height, hypoplastic left heart syndrome, body mass, arterial oxygen saturation, and pulmonary atresia. These combined predictor variables represent 67.8% of importance for the risk of mortality in the Random Forest algorithm.

Conclusions

The representativeness of “hospital death” is greater in patients up to 66 cm in height and body mass index below 13.0 for InCor’s patients. The proportion of “hospital death” declines with the increased arterial oxygen saturation index. Patients with prior hospitalization before surgery had higher “hospital death” rates than who did not required such intervention. The diagnoses groups having the higher fatal outcomes probability are aligned with the international literature. A web application is presented where researchers and providers can calculate predicted mortality based on the CgntSCORE on any web browser or smartphone.

The Evolving Surgical Burden of Fontan Failure: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND

Fontan failure often requires surgical therapy in the form of Fontan revision or heart transplantation. We sought to characterize national trends in the surgical burden of Fontan failure and identify risk factors for adverse outcomes.

METHODS

Fontan patients undergoing Fontan revision or transplantation from January 2010 to June 2018 were included. We evaluated baseline characteristics and outcomes and used multivariable logistic regression to identify risk factors for operative mortality and composite mortality and major morbidity.

RESULTS

A total of 1135 patients underwent Fontan revision (n = 598) or transplantation (n = 537) at 100 centers. Transplantations increased from 34 in 2010 to 76 in 2017, largely owing to an increase in patients with hypoplastic left heart syndrome (HLHS) (18 in 2010 to 49 in 2017), while Fontan revision decreased (75 in 2010 to 49 in 2017). Transplantation patients were younger (median 14 years of age vs 18 years of age; P < .001), more often had preoperative risk factors (66% vs 40%; P < .001), and more often had HLHS (51% vs 15%; P < .001). Operative mortality and composite major morbidity and mortality were 7.6% and 35% for transplantation and 7.1% and 22% for Fontan revision, respectively. Multivariable risk factors for mortality included older age (odds ratio [OR], 1.08/y; P = .007), presence of preoperative risk factors (OR, 3.33; P = .002), and concomitant pulmonary artery reconstruction (OR, 2.7; P = .029) for Fontan revision but only older age (OR, 1.06/y; P = .020) for transplantation.

CONCLUSIONS

Both transplantation and Fontan revision are associated with high morbidity and mortality. There has been evolution of practices in surgical therapy for Fontan failure, perhaps related to rising prevalence of HLHS staged palliation.

The Society of Thoracic Surgeons National Database 2019 Annual Report

The Society of Thoracic Surgeons (STS) National Database was established in 1989 as an initiative for quality improvement and patient safety for cardiothoracic surgery. The STS National Database has 4 components, each focusing on a distinct discipline-Adult Cardiac Surgery, General Thoracic Surgery, Congenital Heart Surgery, and mechanical circulatory support with the STS Interagency Registry for Mechanical Circulatory Support (Intermacs)/Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) Database. In December 2015, The Annals of Thoracic Surgery began publishing a monthly series of scholarly articles on outcomes analysis, quality improvement, and patient safety. This article provides the fourth annual summary of the status of the STS National Database.