Soluble Thrombomodulin Levels are Related to Inflammation after Coronary Bypass Surgery

Background: Soluble Thrombomodulin (sTM) is released from endothelial cells after injury by activated leukocytes in inflammatory states and it has been associated with worse prognosis in inflammatory conditions. The purpose of this study was to analyze the association between levels of sTM and inflammation and to describe the possible explanations about association between sTM and post-operative complications. Methods and Materials: We measured levels of sTM, IL6 and leukocytes in different moments during the first month in 18 patients after coronary by-pass graft surgery. Chisquare test and Fisher test were used for categorical variables. For continuous variables we used either Student t test or Wilcoxon rank-sum test depending on whether the data were normally distributed. Results: The levels of sTM increased during the first post-surgery week, and then decreased to values similar to those recorded pre-operatively. IL6 peaked at after 24 hours, and significantly correlated with white blood cell count (Spearman 0.69, p=<0.0001). There was a significant association between sTM at T3 and white blood cells count at T1 (p=0.01224). Two patients had three or more post-operative complications, and they presented higher levels of sTM. Conclusions: We found a transient increase in sTM during the first week after CABG associated with an inflammatory response and leukocytosis. These changes could imply endothelial dysfunction after surgery and may represent prognostic factors for outcomes.