SYSTEMIC RELEASE OF THROMBOMODULIN, BUT NOT FROM THE CARDIOPLEGIC, REPERFUSED HEART DURING OPEN-HEART-SURGERY

Thrombomodulin is a potential marker of endothelial injury. Plasma thr ombomodulin was measured in concomitant arterial and coronary sinus sa mples in 9 patients undergoing elective coronary artery bypass surgery with cardiopulmonary bypass (CPB, 88+/-14 min) (mean+/-SD) and cold, crystalloid, antegrade cardioplegia (44+/-14 min). Arterial thrombomod ulin was 17+/-6 ng/ml before surgery, and decreased to 10+/-5 ng/ml af ter heparinization (p<0.008 compared to initial value). During CPB thr ombomodulin increased, with a maximal level of 23+/-7 ng/ml (p<0.008 v s initial value) 40 min after aortic declamping. No difference between arterial and coronary sinus concentrations was detected during reperf usion of the heart. In conclusion, plasma thrombomodulin is decreased by heparin, and increased during CPB. Consequently, thrombomodulin may be used to evaluate endothelial injury during CPB. However, as there is no specific intracoronary release of thrombomodulin during reperfus ion, thrombomodulin is not a suitable marker of coronary endothelial i njury after cardioplegia