Predictive value of creatine kinase-MB in newborns with congenital heart disease

Background Creatine kinase-MB was highly related to myocardial cell injury in cardiac diseases. This study aimed to quantify plasma concentrations of creatine kinase-MB, a biomarker of myocardial injury, in neonates diagnosed with congenital heart disease (CHD) and to determine the predictive capacity of creatine kinase-MB levels for patient outcomes. Patients and methods This prospective observational cohort study included 60 full-term neonates who were divided into two equal groups: CHD group (cases): full-term newborns admitted to the neonatal ICU with CHD, diagnosed by early screening echocardiography. Control group: healthy newborns, matched for age and sex, were enrolled as a control group. Echocardiographic assessment was performed on all neonates. The plasma level of creatine kinase-MB was evaluated on day 1 after an early screening echocardiography study by an immune-inhibition assay in the clinical chemistry laboratory. A 3-month follow-up period was conducted for all participants, during which data on mortality and readmission were collected. Results Plasma creatine kinase-MB was significantly elevated in CHD neonates. Creatine kinase-MB level was correlated with the echocardiographic parameters. Creatine kinase-MB was markedly elevated in neonates with severe CHD lesions and with a poor prognosis, indicating more myocardial injury in these newborns. The best cutoff point of 24 U/l plasma creatine kinase-MB could be used as a predictive biomarker in neonates with CHD, with 80% sensitivity, 73% specificity, and 76% accuracy (area under the curve=0.866). Conclusion Elevated plasma concentrations of creatine kinase-MB were observed in neonates with CHD, and these levels demonstrated utility as reliable predictors of unfavorable outcomes in these infant.