Inflammatory cytokines and soluble receptors after coronary artery bypass grafting

Much interest has been focused on the overexpression of proinflammatory cyt okines, but studies on their soluble receptors are rare. For a comprehensiv e picture of cytokine activation in cardiac surgery, a combination of cytok ines and the corresponding soluble receptor concentration should be determi ned. Blood samples were collected from the radial artery and coronary sinus perioperatively in ten patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. TNT-alpha, IL-6, sTNFRI, sTNFRII, and sIL-6R levels in the plasma were determined. Systemic TNFRI, TNFRII and IL-6 incre ased significantly after reperfusion to the myocardium, while perioperative systemic sIL-6r levels were similar. Arterial and sinus levels of TNFRI, T NFRII and sIL-6r were similar before cardiopulmonary bypass. Five minutes a fter reperfusion to the myocardium, higher sinus TNFRI and TNFRII and lower sinus sIL-6R levels were observed as compared to the arterial levels. The myocardium release of sTNFRI (r=0.57, P=0.089) and sTNFRII (r=0.64, P=0.047 ) positively correlated with the change of cardiac index after cardiopulmon ary bypass. Myocardium releases sTNFRI and sTNFRII after ischaemic-reperfus ion injury, and this may be of benefit to cardiac performance. sIL-6R is co nstantly being produced in areas other than the myocardium, while sIL-6R le vels are reduced by consumption in the myocardium after ischaemic-reperfusi on injury. (C) 2001 Academic Press.