Heart is one of the susceptible organs which could be damaged during Coronary Artery Bypass Grafting because of hypoperfusion. Cardiac Troponin I is a sensitive marker which increases immediately after myocardial damages due to poor coronary blood supply. Decrease in central venous oxygen saturation has also been demonstrated in various conditions especially myocardial infarction. The present study aimed to evaluate relationship between central venous oxygen saturation and post-operative cardiac Troponin I in Coronary Artery Bypass Grafting, and find its relations to post-operative laboratory and clinical outcomes. This prospective study was conducted on 53 patients who underwent elective CABG. After anesthesia induction, measurement of Scvo2 was done by central venous catheter after surgery and arterial blood samples were taken for measuring Troponin I before and 24 hours after surgery. The correlation between Scvo2 and other variables was assessed using nonparametric tests, such as Spearman correlation and Mann-Whitney test. Besides, P<0.05 was considered as statistically significant. Among the 53 study patients, 29 (54.8%) were male and 24 (45.2%) were female, with the mean age of 61.02±10.42 years. The results showed an inverse association between Scvo2 and cardiac Troponin I that was checked after the operation (P=0.012, r=-0.348). The study results revealed a reverse relationship between Scvo2 and Troponin I. Therefore, we can conclude that changes in Scvo2 can predict the probability of myocardial damage and cardiac prognosis in early postoperative period. Future longitudinal and cohort studies are recommended to be conducted to follow the patients for long-term outcomes.
