Circulating histones for predicting prognosis after cardiac surgery: a prospective study

The objective of this study was to assess the perioperative changes in circulating histones and their relationships with other biomarkers and clinical outcomes after cardiac surgery with cardiopulmonary bypass (CPB) in patients.

Forty-eight patients with congenital cardiac diseases undergoing corrective procedure with CPB were prospectively enrolled in this study. Circulating histones, N-terminal pro-brain natriuretic peptide (NT-proBNP), procalcitonin (PCT) and C-reactive protein (CRP) were measured preoperatively (T0) and at 0 (T1), 24 (T2), 48 (T3) and 72 (T4) h postoperatively. The relationships between biomarkers and clinical outcomes were analysed.

Circulating histones, NT-proBNP, PCT and CRP increased significantly postoperatively, with histones reaching the peak value earliest at T1. Circulating histone levels were higher in patients with adverse events. Receiver operating characteristic curve analysis showed that peak histone levels had a better predictive value for adverse events postoperatively. Peak histone levels correlated with the peak level of NT-proBNP (r = 0.563, P < 0.01), PCT (r = 0.551, P < 0.01), CRP (r = 0.606, P < 0.01) and clinical parameters such as ventilation time (r = 0.601, P < 0.01) and intensive care unit time (r = 0.623, P < 0.01).

Circulating histones reached peak levels faster than NT-proBNP, PCT and CRP. Furthermore, peak histone levels correlated with biomarkers and postoperative clinical outcomes. Circulating histones may be used as a prognostic indicator for patients after cardiac surgery with CPB.

ClinicalTrials.gov (ID: NCT02325765).