Analysis of risk factors of low cardiac output syndrome after congenital heart disease operation: what can we do

Connecting Transcriptomics with Computational Modeling to Reveal Developmental Adaptations in the Human Pediatric Myocardium

Background

Nearly 1% or 1.3 million babies are born with congenital heart disease (CHD) globally each year - many of whom will require palliative or corrective heart surgery within the first few years of life. A detailed understanding of cardiac maturation can help to expand our knowledge on cardiac diseases that develop during gestation, identify age-appropriate cardiovascular drug therapies, and inform clinical care decisions related to surgical repair, myocardial preservation, or postoperative management. Yet, to date, our knowledge of the temporal changes that cardiomyocytes undergo during postnatal development is largely limited to animal models.

Methods

Right atrial tissue samples were collected from n=117 neonatal, infant, and pediatric patients undergoing correct surgery due to (acyanotic) CHD. Patients were stratified into five age groups: neonate (0-30 days), infant (31-364 days), toddler to preschool (1-5 years), school age (6-11 years), and adolescent to young adults (12-32 years). We measured age-dependent adaptations in cardiac gene expression, and used computational modeling to simulate action potential and calcium transients.

Results

Enrichment of differentially expressed genes (DEG) was explored, revealing age-dependent changes in several key biological processes (cell cycle, cell division, mitosis), cardiac ion channels, and calcium handling genes. Gene-associated changes in ionic currents exhibited both linear trends and sudden shifts across developmental stages, with changes in calcium handling ( I NCX ) and repolarization ( I K1 ) most strongly associated with an age-dependent decrease in the action potential plateau potential and increase in triangulation, respectively. We also note a shift in repolarization reserve, with lower I Kr expression in younger patients, a finding likely tied to the increased amplitude of I Ks triggered by elevated sympathetic activation in pediatric patients.

Conclusion

This study provides valuable insights into age-dependent changes in human cardiac gene expression and electrophysiology among patients with CHD, shedding light on molecular mechanisms underlying cardiac development and function across different developmental stages.

Anisocytosis as a possible predictor of low cardiac output syndrome in children undergoing mitral valve surgery

PURPOSE

Mitral valve surgery in children involves correcting congenital and acquired pathologies, with a reported mortality rate of 0.9%. Low cardiac output syndrome (LCOS) is a serious complication with the incidence of 20-25%. The aim of the study was to estimate possible prognostic factors of LCOS in children undergoing mitral valve procedure.

MATERIAL AND METHOD

This single-center retrospective analysis enrolled children aged <18 years who underwent mitral valve surgery during 24 year period. Preoperative clinical and laboratory parameters, and operative factors were analyzed.

RESULTS

Thirty consecutive pediatric patients (11 (37%) males and 19 (63%) females) in median (Q1 - Q3) age of 57 (25-115) months, who underwent mitral valve replacement, were included. The 30-day mortality was 7% (2 patients) and was related to postoperative multiorgan failure. LCOS occurred in 8 (27%) children. The receiver operator curve (ROC) analysis established parameters that have predictive value for LCOS occurrence: cardiopulmonary bypass (CPB) time, with 89 ​min as optimal cut-off point (AUC ​= ​0.744, p ​= ​0.011) yielding sensitivity of 100% and specificity of 42.9%; left ventricular ejection fraction (LVEF) ​< ​60 % (AUC ​= ​0.824, okp ​= ​0.001) with sensitivity of 62.5% and specificity of 93.75%; and red blood cell distribution width (RDW) above 14.5 % (AUC ​= ​0.840, p ​< ​0.001; sensitivity of 87.5% and specificity of 75%).

CONCLUSIONS

In mitral valve replacement in pediatric patients, CPBtime above 89 ​min, preoperative LVEF below 60% and preoperative RDW above 14.5% can be regarded as the potential predictors of LCOS.

Acute renal injury after aortic arch reconstruction with cardiopulmonary bypass for children: prediction models by machine learning of a retrospective cohort study

BACKGROUND

Acute renal injury (AKI) after aortic arch reconstruction with cardiopulmonary bypass leads to injury of multiple organs and increases perioperative mortality. The study was performed to explore risk factors for AKI. We aim to develop a prediction model that can be used to accurately predict AKI through machine learning (ML).

METHODS

A retrospective analysis was performed on 134 patients with aortic arch reconstruction with cardiopulmonary bypass who were treated at our hospital from January 2002 to January 2022. Risk factors for AKI were compositive and were evaluated with comprehensive analyses. Six artificial intelligence (AI) models were used for machine learning to build prediction models and to screen out the best model to predict AKI.

RESULTS

Weight, eGFR, cyanosis, PDA, newborn birth and duration of renal ischemia were closely related to AKI. By integrating the results of the training cohort and validation cohort, we finally confirmed that the logistic regression model was the most stable model among all the models, and the logistic regression model showed good discrimination, calibration and clinical practicability. Based on 6 independent factors, the dynamic nomogram can be used as a predictive tool for clinical application.

CONCLUSIONS

DHCA could be considered in aortic arch reconstruction if additional perfusion of lower body were not performed especially when renal ischemia is greater than 30 min. Machine Learning models should be developed for early recognition of AKI.

TRIAL REGISTRATION

ChiCTR, ChiCTR2200060552. Registered 4 june 2022.

Prophylactic use of levosimendan in preoperative setting for surgical repair of congenital heart disease in children

Introduction

Low cardiac output syndrome (LCOS) is a significant cause of morbidity and the leading cause of mortality after pediatric cardiac surgery. Levosimendan has been shown safe and effective in pediatrics to treat LCOS. We aimed to review our local strategy with preoperative prophylactic Levosimendan infusion to minimize LCOS after heart surgery in identified high-risk patients.

Methods

Retrospective monocentric study. As there is no reliable cardiac output measurement in children, we recorded hemodynamic parameters as surrogates of cardiac output after extracorporeal circulation through an electronic patient survey system at different time points.

Results

Seventy-two children received Levosimendan before surgery between 2010 and 2019. As expected, most patients were newborns and infants with prolonged open-heart surgeries. Median cardiopulmonary bypass time was 182 [137-234] min, and aortic clamping time was 95 [64-126] min. The postoperative hemodynamic parameters, vasoactive-inotropic score, and urine output remained stable throughout the first 48 h. Only a tiny portion of the patients had combined surrogate markers of LCOS with a maximal median arterial lactate of 2.6 [1.9-3.5] mmol/L during the first six postoperative hours, which then progressively normalized. The median arterio-venous difference in oxygen saturation was 31 [23-38] % between 12 and 18 h post-surgery and gradually decreased. The median venous-to-arterial CO2 difference was the highest at 10 [7-12] mmHg between 12 and 18 h post-surgery. Nine patients (13%) required extracorporeal membrane oxygenation. No patient required dialysis or hemofiltration. Mortality was 0%.

Conclusion

Before congenital heart surgery, preoperative prophylactic administration of Levosimendan seems effective and safe for decreasing occurrence and duration of LCOS in high-risk children.

An Assessment of the Practice of Neuromuscular Blockade and the Association Between Its Prophylactic Use and Outcomes Among Postoperative Pediatric Cardiac Patients

OBJECTIVES

The authors investigated the management of neuromuscular blocking agents (NMBAs) for pediatric patients after cardiac surgery, and compared the outcomes of patients who received prophylactic NMBA (pNMBA) infusions and patients without pNMBA infusions.

DESIGN

A retrospective cohort study.

SETTING

At a tertiary teaching hospital.

PARTICIPANTS

Patients younger than 18, with congenital heart disease, who underwent cardiac surgery.

INTERVENTIONS

Commencement of NMBA infusion in the first 2 hours after surgery MEASUREMENTS AND MAIN RESULTS: The primary endpoint was a composite of one or more of the following major adverse events (MAEs) that occurred within 7 days after surgery: death from any cause, a circulatory collapse that needed cardiopulmonary resuscitation, and requirement for extracorporeal membrane oxygenation. The secondary endpoints included the total duration of mechanical ventilation for the first 30 days after surgery. A total of 566 patients were included in this study. The MAEs occurred in 13 patients (2.3%). An NMBA was commenced within 2 hours after surgery in 207 patients (36.6%). There were significant differences in the incidence of postoperative MAEs between the pNMBA group and the non-pNMBA group (5.3% v 0.6%; p < 0.001). In multivariate regression models, pNMBA infusion was not significantly associated with the incidence of MAEs (odds ratio: 1.79, 95% CI: 0.23-13.93, p = 0.58), but was significantly associated with prolonged mechanical ventilation by 3.85 days (p < 0.001).

CONCLUSIONS

Postoperative prophylactic neuromuscular blockade after cardiac surgery can be associated with prolonged mechanical ventilation, but has no association with MAEs among pediatric patients with congenital heart disease.

Total Anomalous Pulmonary Venous Return in the Time of SARS-CoV-2-Case Report

The management of children with complex and life-threatening heart malformations became a clinical conundrum during the SARS-CoV-2 pandemic. The pathophysiological features of the new coronavirus infection have raised major dilemmas regarding the postoperative evolution of an infected patient, and the epidemiological limitations have tightened the criteria for selecting cases. We present the case of a newborn diagnosed with total anomalous pulmonary venous return (TAPVR) who underwent surgical repair of the defect with favorable outcome, despite a prior diagnosis of SARS-CoV-2 infection. We discuss the medical and surgical management of TAPVR, highlighting possible management difficulties brought by the SARS-CoV-2 pandemic.

Novel cfDNA Methylation Biomarkers Reveal Delayed Cardiac Cell Death after Open-heart Surgery

The use of cardiopulmonary bypass (CPB) is thought to cause delayed cardiac damage. DNA methylation-based liquid biopsies are novel biomarkers for monitoring acute cardiac cell death. We assessed cell-free DNA molecules as markers for cardiac damage after open-heart surgery. Novel cardiomyocyte-specific DNA methylation markers were applied to measure cardiac cfDNA in the plasma of 42 infants who underwent open-heart surgery. Cardiac cfDNA was elevated following surgery, reflecting direct surgery-related tissue damage, and declined thereafter in most patients. The concentration of cardiac cfDNA post-surgery correlated with the duration of CPB and aortic cross clamping. Strikingly, cardiac cfDNA at 6 h predicted duration of mechanical ventilation and maximal vasoactive-inotropic score better than did maximal troponin levels. Cardiac cfDNA reveals heart damage associated with CPB, and can be used to monitor cardiac cell death, to predict clinical outcome of surgery and to assess performance of cardioprotective interventions.

Risk factors of postoperative low cardiac output syndrome in children with congenital heart disease: A systematic review and meta-analysis

BACKGROUND

Low cardiac output syndrome (LCOS) is the most common complication after cardiac surgery, which is associated with the extension of postoperative hospital stay and postoperative death in children with congenital heart disease (CHD). Although there are some studies on the risk factors of LCOS in children with CHD, an unified conclusion is lack at present.

PURPOSES

To synthesize the risk factors of LCOS after CHD in children, and to provide evidence-based insights into the early identification and early intervention of LCOS.

METHODS

The databases of the China National Knowledge Infrastructure (CNKI), Wanfang Database, China Science and Technology Journal Database (VIP), PubMed, Cochrane Library, Embase and Web of Science were searched for relevant articles that were published between the establishing time of each database and January 2022. Based on retrospective records or cohort studies, the influencing factors of postoperative low cardiac output in children with congenital heart disease were included in Meta analysis.This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The risk of bias was evaluated according to the Newcastle-Ottawa Scale (NOS). RevMan 5.4 software was used to conduct the meta-analysis.

RESULTS

A total of 1,886 records were screened, of which 18 were included in the final review. In total, 37 risk factors were identified in the systematic review. Meta- analysis showed that age, type of CHD, cardiac reoperation, biventricular shunt before operation, CPB duration, ACC duration, postoperative residual shunt, cTn-1 level 2 h after CPB > 14 ng/ml and postoperative 24 h MR-ProADM level > 1.5 nmol/l were independent risk factors of LCOS. Additionally, the level of blood oxygen saturation before the operation was found to have no statistically significant relationship with LOCS.

CONCLUSION

The risk factors of postoperative LCOS in children with CHD are related to disease condition, intraoperative time and postoperative related indexes, so early prevention should be aimed at high-risk children.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022323043.