Hyperprocalcitonemia in patients with perioperative myocardial infarction after cardiac surgery

OBJECTIVE: To describe and compare procalcitonin (PCT) concentrations after cardiac surgery in uncomplicated patients and in patients with perioperative myocardial infarction (PMI). DESIGN: Retrospective comparative study. SETTING: One university hospital. PATIENTS: Fifty-eight adult patients undergoing cardiac surgery. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: In a first step, plasma PCT and C-reactive protein concentrations were measured preoperatively and until 72 hrs postoperatively in ten consecutive patients who underwent uncomplicated cardiac surgery. PCT concentrations increased progressively from the end of cardiopulmonary bypass (0.09 +/- 0.09 ng/mL), peaked at 24 hrs postoperatively (1.14 +/- 1.24 ng/mL), and began to decrease at 48 hrs. C-reactive protein appeared to peak at 48 hrs (from 5.8 +/- 11.7 mg/L preoperatively to 265.1 +/- 103.5 mg/L on the second postoperative day). In a second step, PCT concentrations were measured at day one in 23 patients (PMI group) who presented high postoperative plasma cardiac troponin I concentrations and were compared with PCT concentrations observed in 25 matched uncomplicated patients. All patients were free from infection. PCT in the PMI group was significantly higher than in the control group (27.1 +/- 63.2 vs. 2.0 +/- 2.4 ng/mL, respectively; p =.0053). CONCLUSION: Because high plasma concentrations of PCT were found in patients with PMI after cardiac surgery, it may be suggested that, in the early postoperative period, elevated plasma PCT concentrations should be interpreted with caution regarding infection diagnosis.