Predictive Value of Myocardial Markers for Early Postoperative Mortality in Children with Congenital Heart Disease

To investigate the influencing factors of postoperative creatine kinase-MB (CK-MB) elevation in children with congenital heart disease and its peak value in predicting early postoperative mortality. The clinical data of 521 children with congenital heart disease under the age of 14 who underwent elective surgery in Beijing Children's Hospital from December 2018 to December 2020 were retrospectively analyzed. Stepwise multiple linear regression was used to analyze independent risk factors for postoperative CK-MB elevation, receiver operating characteristic (ROC) curve was used to determine the predictive value of postoperative CK-MB peak, CK peak, and LDH peak on mortality, and linear correlation and regression analysis were used to analyze the interdependence among postoperative CK-MB peak, CK peak, and LDH peak, and multivariate Logistic regression was used to identify independent risk factors for early postoperative mortality. Preterm birth (P = 0.004), ventriculotomy (P = 0.009), the re-establish of bypass (P = 0.007), cardiopulmonary bypass time (P = 0.024), deep hypothermic circulatory arrest time (P = 0.000), assisted ventilation time (P = 0.049), CK peak (P = 0.000), and LDH peak (P = 0.000) were independently associated with increased postoperative CK-MB elevation. The ROC curve showed that CK-MB peak had the strongest predictive value for death (AUC = 0.924), followed by LDH peak (AUC = 0.864) and CK peak (AUC = 0.758). The cut-off value of the postoperative CK-MB peak was 144.5 IU/L, with a sensitivity of 87% and a specificity of 97%. CK-MB peak was moderately correlated with CK peak (Pearson Correlation coefficient r = 0.514, P = 0.000) and strongly correlated with LDH peak (Pearson Correlation coefficient r = 0.601, P = 0.000). Multivariate analysis showed that delayed chest closure (OR = 4.865, P = 0.004) and postoperative CK-MB peak (OR = 1.031, P = 0.000) were independent risk factors for postoperative mortality. The postoperative CK-MB peak has a certain predictive value for the early postoperative mortality of children with congenital heart disease. It is affected by many factors, and the risk of mortality is significantly increased in children with severely elevated postoperative CK-MB.