The relationship of serum creatinine and cardiac troponin I after off-pump coronary artery bypass graft surgery

ABSTRACT

BACKGROUND: Renal dysfunction is an independent risk factor of cardiac dysfunction and one of common complications after cardiac surgery. This study was designed to evaluate the relationship between serum creatinine (s-Cr) and cardiac troponin I (cTnI) in off-pump coronary artery bypass graft surgery (OPCAB). METHODS: Data, from 13 patients underwent OPCAB, were analyzed in prospective fashion. The levels of s-Cr and cTnI were evaluated before and after OPCAB. The correlations of s-Cr and TnI were analyzed in the patients with cardiac dysfunction assessed by low cardiac output or stroke volume at end of surgery. RESULTS: Patients with preoperatively elevated s-Cr (female, > or =1.2 microg/L; male, > or =1.5microg/L) showed higher incidence of elevated s-Cr and elevated cTnI (> or =0.68microg/L) on arrival at intensive care unit (POD-0), postoperative 12 hours (POD-1) and postoperative 36 hours (POD-2) (P< 0.05). Patients with preoperatively elevated cTnI showed higher incidence of elevated cTnI at POD-0, POD-1 and POD-2 (P< 0.05). In 7 patients with low cardiac index (< 2.0 L/min/m2) or stroke volume index (<40 mL/beat/m2) at end of surgery, the increases of s-Cr and cTnI showed positive correlation at POD-0, POD-1 and POD-2 (correlation coefficient 0.818, 0.864 and 0.785, respectively). CONCLUSIONS: The increases of s-Cr and cTnI showed positive correlation in low cardiac output after OPCAB. The results suggested that elevated s-Cr may be an independent predictor of elevated cTnI representing perioperative myocardial injury.