Tumor necrosis factor-alpha and troponin I release in porcine cardiac lymph and coronary sinus blood before and after cardiopulmonary bypass

Abstract

peer reviewedTo assess the concentrations of cardiac troponin I (cTnI) and tumor necrosis factor-alpha (TNFalpha) in cardiac lymph compared with coronary sinus (CS) blood and to measure cardiac lymph flow before and after cardiopulmonary bypass (CPB). In 21 pigs, the main cardiac lymph trunk was cannulated before institution of standardized CPB. Lymph flow, cTnI and TNFa in cardiac lymph and CS blood were measured before and after CPB for 6 hours. Before CPB, cTnI concentration was 215 +/- 36 nglml in cardiac lymph and 0.5 +/- 0.1 nglml in CS blood, respectively. After aortic declamping a significant elevation of cTnI values was measured in cardiac lymph and CS blood. cTnl concentration in cardiac lymph and CS blood peaked 6 hrs after CPB (10,556 +/- 4,735 vs. 22.2 +/- 3.7 nglml, p < 0.01). TNFalpha concentration at baseline was 23.2 +/- 5.6 pg/ml in lymph and 18.7 +/- 9.5 pg/ml in CS blood, and there was no significant release of TNFalpha up to the end of the experiment. Baseline cardiac lymph flow was 3.07 +/- 0.35 ml/h and declined after aortic clamping (0.72 +/- 0.16 ml/h; p < 0.01) and peaked one hour after CPB (5.66 +/- 0.97 ml/h; p < 0.01). In conclusion, very high cTnI concentrations in cardiac lymph suggest serious perioperative myocardial damage after CPB with cardioplegia, which is underestimated by cTnI release into the bloodstream. In our study, the myocardium was not a major source of TNFalpha release