Diagnostic significance of highly sensitive troponins in cardiac surgery

Background: The level of troponins after cardiac surgery always exceeds the reference values, however, the interpretation of these changes is difficult. Aim: To determine the relationship between the high-sensitivity cardiac troponin I and troponin T levels and the risk of heart failure (HF) development within 24 hours after the heart surgery. Methods: A prospective, observational, single-center study included 70 patients undergoing elective heart surgery. The patients were retrospectively divided into two groups based on the development of HF in the first 12 hours after the surgery. The group without HF included 57 patients, the group with HF included 13 patients. Results: The levels of highly sensitive Troponin I (HsTI) in patients who underwent elective heart surgery without complications were 61 times higher than the upper limit of the normal values, in those with the development of HF they were 111 times higher than the upper limit of the normal values. The levels of highly sensitive Troponin T (HsTT) were 25.5 times and 51 times the upper limit of the normal values, respectively. The level of HsTI at the end of the surgery can be a predictor of the HF development, regardless of the use of cardiac bypass (threshold value =1483 ng/l), as well as a predictor of the need for inotropic support for 2 days or more, regardless of the operation type (threshold value = 1573 ng/l). There was a direct moderate correlation of the HsTI level at the end of the operation and 6 hours after the operation with cumulative hemohydrobalance for 24 hours, which was 60% higher in patients with HF than that in patients without complications. Conclusion: In uncomplicated patients, the level of highly sensitive troponins T and I in the postoperative period is 25–61 times higher than the upper limit of the normal values, and with the HF development it is 51–111 times higher. Highly sensitive troponins can be considered as predictors of the HF development and the duration of inotropic support. The increase in the level of troponins is influenced by the duration of cardiac bypass and the volume of infusion therapy in the perioperative period.