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

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.

Morbidity and Mortality in Adult Congenital Heart Surgery: Physiologic Component Augments Risk Prediction

BACKGROUND

We sought to evaluate whether the anatomic and physiologic stratification system (ACAP score), released as part of the American College of Cardiology/American Heart Association updated guidelines for management of adult congenital heart disease (ACHD) in 2018, better estimated mortality and morbidity after cardiac operations for ACHD.

METHODS

The ACAP score was determined for 318 patients (age ≥18 years) with ACHD undergoing heart surgery at our institution between December 2001 and August 2019. The primary end point was perioperative mortality. The secondary aim was to evaluate the performance of the ACAP, The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) Congenital Heart Surgery Mortality Categories, and ACHS mortality scores/categories at predicting a composite adverse outcome of perioperative mortality, prolonged ventilation, and renal failure requiring replacement therapy. Logistic regression models were built to estimate mortality and the composite outcome using anatomic and physiologic components independently and together. Receiver operating characteristic curves were created, and area under the curves were compared using the Delong test.

RESULTS

The median age was 37 years (interquartile range, 26.3-50.0 years). There were 9 perioperative mortalities (2.8%). With respect to perioperative mortality, the area under the curve using the anatomic component only was 0.74, which improved to 0.81 after including physiologic severity (P = .05). When physiologic severity was added to the model for the composite outcome, the discriminatory abilities of the ACHS mortality score and the STAT categories increased significantly to 0.83 (95% CI, 0.75-0.91; P = .02) and 0.82 (95% CI, 0.73-0.90; P = .04), comparable to the predictive power of ACAP.

CONCLUSIONS

Physiologic severity augments ability to predict mortality and morbidity after cardiac surgery for ACHD. There is need for more robust ACHD-specific risk models.

Immune urinary biomarkers predict infant cardiac surgery-associated acute kidney injury

BACKGROUND

Acute kidney injury (AKI) occurs frequently after infant cardiac surgery and is associated with poor outcomes, including mortality and prolonged length of stay. AKI mechanisms are poorly understood, limiting therapeutic targets. Emerging data implicates dysregulated immune activation in post-cardiac surgery AKI development. We sought to identify immune-mediated AKI biomarkers after infant cardiopulmonary bypass (CPB)-assisted cardiac surgery.

METHODS

A single-center prospective study of 126 infants less than 1 year old undergoing CPB-assisted surgery enrolled between 10/2017 and 6/2019. Urine samples were collected before CPB and at 6, 24, 48, and 72 h after surgery. Immune-mediated biomarkers were measured using commercial ELISA and Luminex™ multiplex kits. Based on subject age, neonatal KDIGO (< 1 month) or KDIGO criteria defined AKI. The Kruskal-Wallis rank test determined the relationship between urinary biomarker measurements and AKI.

RESULTS

A total of 35 infants (27%) developed AKI. AKI subjects were younger, underwent more complex surgery, and had longer CPB time. Subjects with AKI vs. those without AKI had higher median urinary chemokine 10 (C-X-C motif) ligand levels at 24, 48, and 72 h, respectively: 14.3 pg/ml vs. 5.3 pg/ml, 3.4 pg/ml vs. 0.8 pg/ml, and 1.15 pg/ml vs. 0.22 pg/ml (p < 0.05) post-CPB. At 6 h post-CPB, median vascular cell adhesion protein 1 (VCAM) levels (pg/mL) were higher among AKI subjects (491 pg/ml vs. 0 pg/ml, p = 0.04).

CONCLUSIONS

Urinary CXCL10 and VCAM are promising pro-inflammatory biomarkers for early AKI detection and may indicate eventual AKI therapeutic targets. A higher resolution version of the Graphical abstract is available as Supplementary information.

Clinical Characteristics and Outcomes in Adults With Moderate-to-Severe Complexity Congenital Heart Disease Undergoing Palliation or Surgical Repair

Background

Congenital heart disease (CHD) survival rate has improved dramatically due to advances in diagnostic and therapeutic techniques. However, concerning the unrepaired CHD population of moderate and severe complexity, the data regarding risk predictors and surgical outcomes are scarce. Our aim was to describe the surgical results and predictors of in-hospital outcomes in adult patients with moderate-to-severe complexity CHD that were not repaired in childhood.

Methods

We conducted a retrospective cohort study that included 49 adult patients with moderate-to-complex CHD who were treated in a single medical centre. Clinical and echocardiographic variables were obtained on admission, after surgical procedures and during follow-up.

Results

Most of the patients were female (66%). Left ventricular ejection fraction and right ventricular outflow tract fractional shortening were within the normal range. The median pulmonary artery systolic pressure was 37 (27-55) mm Hg. The median time was 118 (80-181) minutes for extracorporeal circulation and 76 (49-121) minutes for aortic cross-clamping. The most frequent complication was postoperative complete atrioventricular block (12.2%). In-hospital survival rate was 87.7%. The development of low cardiac output syndrome with predominant right ventricle failure in the postoperative period was the most important predictor of in-hospital death (P = 0.03).

Conclusions

Deciding to treat adults with CHD is challenging in moderate and severe unrepaired cases. Adequate clinical, functional, and imaging evaluation is essential to determine each patient's suitability for surgical management and to achieve the best clinical outcome for this population.

Vasoactive-ventilation-renal score and outcomes in infants and children after cardiac surgery

Introduction

There is a need to index important clinical characteristics in pediatric cardiac surgery that can be obtained early in the postoperative period and accurately predict postoperative outcomes.

Methodology

A prospective cohort study was conducted in the pediatric cardiac ICU and ward on all children aged <18 years undergoing cardiac surgery for congenital heart disease from September 2018 to October 2020. The vasoactive-ventilation-renal (VVR) score was analyzed to predict outcomes of cardiac surgeries with a comparison of postoperative variables.

Results

A total of 199 children underwent cardiac surgery during the study period. The median (interquartile range) age was 2 (0.8-5) years, and the median weight was 9.3 (6-16) kg. The most common diagnoses were ventricular septal defect (46.2%) and tetralogy of Fallot (37.2%). At the 48th h, area under the curve (AUC) (95% CI) values were higher for the VVR score than those for other clinical scores measured. Similarly, at the 48th h, AUC (95% CI) values were higher for the VVR score than those for the other clinical scores measured for the length of stay and mechanical ventilation.

Discussion

The VVR score at 48 h postoperation was found to best correlate with prolonged pediatric intensive care unit (PICU) stay, length of hospitalization, and ventilation duration, with the greatest AUC-receiver operating characteristic (0.715, 0.723, and 0.843, respectively). The 48-h VVR score correlates well with prolonged ICU, hospital stay, and ventilation.