Unchanged Plasma Levels of the Soluble Urokinase Plasminogen Activator Receptor in Elective Coronary Artery Bypass Graft Surgery Patients and Cardiopulmonary Bypass Use

Objective and Design: The soluble urokinase plasminogen activator receptor (suPAR) has been recently recognized as a potential biological marker of various disease states, but the impact of a major surgical intervention on the suPAR level has not yet been established. The aim of our study was to investigate if the induction of a systemic inflammatory reaction in response to cardiopulmonary bypass would be accompanied by an increase in the plasma suPAR level. Methods and Subjects: Patients undergoing coronary artery bypass grafting under cardiopulmonary bypass (CPB) were added. Based on the baseline suPAR level, patients were divided into group 1 (suPAR within normal range) or group 2 (suPAR above range). Blood was collected before the induction of anesthesia and 6 and 24 hours after surgery. Plasma suPAR, IL-6, IL-8, TNF-a, troponin I, NT-proBNP, and NGAL were quantified to assess the impact of surgical trauma on these markers. Results: The baseline suPAR level was within the normal range in 31 patients (3.3 ng/mL), and elevated in 29 (5.1 ng/mL) (p, 0.001). Baseline mediators of systemic inflammatory reaction concentrations (IL-6, TNF-alpha, and IL-8) and organ injury indices (troponin I, NT-proBNP, and NGAL) were low and increased after surgery in all patients (p < 0.05). The surgery did not cause significant changes in the suPAR level either at 6 or 24 hours after, however the difference between groups observed at baseline remained substantial during the postoperative period. Conclusions: There was no change in the suPAR level observed in patients subjected to elective cardiac coronary artery bypass surgery and CPB, despite activation of a systemic inflammatory reaction.