Development of a Novel Society of Thoracic Surgeons Adult Congenital Mortality Risk Model

Risk of Cardiac Reoperation: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND

The increasing number of congenital heart disease patients undergoing reoperative cardiac surgery presents critical and growing challenges. Our objective was to evaluate the association between the number of prior cardiopulmonary bypass operations and operative mortality and morbidity in a national cohort.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) was reviewed for index cardiac operations on cardiopulmonary bypass during 2016 to 2021. Infants and patients with functionally univentricular physiology were excluded. Multivariable logistic regression adjusted for covariates in the STS-CHSD Mortality Risk Model, the STS-European Association for Cardio-Thoracic Surgery (STAT) Mortality Category, and institutional volume.

RESULTS

Of 50,625 eligible operations, 22,100 (44%) were performed on patients with ≥1 prior cardiopulmonary bypass operations. Most common diagnoses were tetralogy of Fallot (4340 of 22,100 [19.6%]), pulmonary atresia/ventricular septal defect (1334 of 22,100 [6.0%]), and aortic stenosis (966 of 22,100 [4.4%]). Operative mortality correlated with number of prior cardiopulmonary bypass operations: 157 of 28,525 (0.6%) for 0, 127 of 13,488 (0.9%) for 1, 81 of 5,664 (1.4%) for 2, 61 of 2039 (3.0%) for 3, 35 of 623 (5.6%) for 4, 10 of 207 (4.8%) for 5, and 5 of 79 (6.3%) for ≥6 operations (P < .001). On multivariable analysis, patients with ≥3 prior cardiopulmonary bypass operations had higher risk of operative mortality (odds ratio, 2.31; P < .001) and major morbidity (odds ratio, 1.60; P < .001). Annual institutional volume and age were not associated with either outcome.

CONCLUSIONS

Three or more prior cardiopulmonary bypass operations was an independent risk factor for operative mortality/morbidity, even after controlling for risk factors and institutional volume. Future research is needed to identify modifiable factors to optimize outcomes, particularly for those with ≥3 prior cardiopulmonary bypass operations.

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.

Cardiac Arrest With or Without Need for Extracorporeal Life Support After Congenital Cardiac Surgery

BACKGROUND

Postoperative cardiac arrest (CA) with or without need for extracorporeal cardiopulmonary resuscitation (ECPR) is one of the most significant complications in the early postoperative period after pediatric cardiac operation. The objective of this study was to develop and to validate a predictive model of postoperative CA with or without ECPR.

METHODS

In this retrospective cohort study, we reviewed data from patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) between July 20, 2020, and December 31, 2021. Variables included demographic data, presence of preoperative risk factors, The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality categories, perioperative data, residual lesion score (RLS), and vasoactive-inotropic score (VIS). We used multivariable logistic regression analysis to develop a predictive model.

RESULTS

The incidence of CA with or without ECPR was 4.4% (n = 24/544). Patients who experienced postoperative CA with or without ECPR were younger (age, 130 [54-816.5] days vs 626 [127.5-2497.5] days; P < .050) and required longer CPB (253 [154-332.5] minutes vs 130 [87-186] minutes; P < .010) and cross-clamp (116.5 [75.5-143.5] minutes vs 64 [30-111] minutes; P < .020) times; 37.5% of patients with an outcome had at least 1 preoperative risk factor (vs 16.9%; P < .010). Our multivariable logistic regression determined that the presence of at least 1 preoperative risk factor (P = .005), CPB duration (P = .003), intraoperative residual lesion score (P = .009), and postsurgery vasoactive-inotropic score (P = .010) were predictors of the incidence of CA with or without ECPR.

CONCLUSIONS

We developed a predictive model of postoperative CA with or without ECPR after congenital cardiac operation. Our model performed better than the individual scores and risk factors.

Risk factors and early outcomes of repeat sternotomy in 1960 adults with congenital heart disease: A 30-year, single-center study

OBJECTIVE

Patients with congenital heart disease (CHD) increasingly live into adulthood, often requiring cardiac reoperation. We aimed to assess the outcomes of adults with CHD (ACHD) undergoing repeat sternotomy at our institution.

METHODS

Review of our institution's cardiac surgery database identified 1960 ACHD patients undergoing repeat median sternotomy from 1993 to 2023. The primary outcome was early mortality, and the secondary outcome was a composite end point of mortality and significant morbidity. Univariable and multivariable logistic regression models were used to determine factors independently associated with outcomes.

RESULTS

Of the 1960 ACHDs patient undergoing repeat sternotomy, 1183 (60.3%) underwent a second, third (n = 506, 25.8%), fourth (n = 168, 8.5%), fifth (n = 70, 3.5%), and sixth sternotomy or greater (n = 33, 1.6%). CHD diagnoses were minor complexity (n = 145, 7.4%), moderate complexity (n = 1380, 70.4%), and major complexity (n = 435, 22.1%). Distribution of procedures included valve (n = 549, 28%), congenital (n = 625, 32%), aortic (n = 104, 5.3%), and major procedural combinations (n = 682, 34.7%). Overall early mortality was 3.1%. Factors independently associated with early mortality were older age at surgery, CHD of major complexity, preoperative renal failure, preoperative ejection fraction, urgent operation, and postoperative blood transfusion. In addition, sternotomy number and bypass time were independently associated with the composite outcome.

CONCLUSIONS

Despite the increase in early mortality with sternotomy number, sternotomy number was not independently associated with early mortality but with increased morbidity. Improvement strategies should target factors leading to urgent operations, early referral, along with operative efficiency including bypass time and blood conservation.