Markers of myocardial injury study

Abstract

Introduction: Low cardiac output syndrome is a post-operative complication that occurs in 25% of neonatal and paediatric patients undergoing cardiac surgery with cardiopulmonary bypass. It is associated with increased morbidity and mortality. Better prediction of its occurrence and earlier management could potentially improve clinical outcomes. Objectives/Aims: Assess the association of low cardiac output state with changes in biomarkers of myocardial injury following cardiac surgery necessitating cardiopulmonary bypass in neonatal and paediatric patients. Methods: This was an ethically approved, blinded prospective study involving 38 neonatal and paediatric patients undergoing cardiac surgery with cardiopulmonary bypass. Patients received conventional management together with assays of troponin T, CK, procalcitonin and CRP preoperatively and then at 0,4,24,48 and 72h postoperatively. Patients were classified as having low cardiac output state or not based on accepted biochemical, inotrope requirement and physiological parameters. Comparison was made between biomarker levels and development of low cardiac output state. Results: Patients with low cardiac output state demonstrated an increased length of stay in the PICU, increased ventilation time, increased heart rate, and reduced mean arterial pressure compared to the no low cardiac output state group. Significant increases, (p<0.001) in troponin T were observed in the low cardiac output state group on admission (1686ng/L vs. 502ng/L) and at 4h postoperatively (1461ng/L vs. 600ng/L). Significant increases, (p<0.001) in CK were also measured in the low cardiac output state group on admission (973U/L vs. 420U/L) and at 4h postoperatively (922U/L vs. 432U/L). Procalcitonin and CRP did not show any significant early differences between the 2 patient groups. Conclusion: Measurement of significantly raised troponin T and or CK on admission and or 4h following cardiac surgery in paediatric and neonatal patients could assist in earlier detection and management of patients with a low cardiac output state.