Induction of inflammatory mediators during reperfusion of the human heart

Background. Cardioplegia and reperfusion may induce an inflammatory reaction, which may contribute to postoperative morbidity and mortality. Methods. Gene expression of cytokines, adhesion molecules, and vasoactive substances was evaluated in left ventricular biopsies taken before cardioplegia (lasting approximately 70 minutes) and after reperfusion (approximately 40 minutes) from 19 patients (5 with valvular or combined disease, 7 with stable angina pectoris, 7 with unstable angina). mRNA was extracted and amplified with a semiquantitative reverse transcription polymerase chain reaction. Results. Cardioplegia-reperfusion increased mRNA for E-selectin by a factor of 17 ± 5 (p < 0.002) (mean ± SEM), interleukin-1β with 9 ± 3 (p < 0.007), tumor necrosis factor-α with 6 ± 3 (p < 0.05), interleukin-2 receptor α chain CD25 with 2 ± 0.6 (p < 0.04), and intercellular adhesion molecule-1 with 2 ± 0.4 (p < 0.005). Before cardioplegia, mRNA for endothelial nitric oxide synthase was predominantly detected in unstable angina patients, and increased by a factor of 11 ± 6 (p < 0.02) during reperfusion. mRNA for endothelin-1 decreased by a factor of 0.5 ± 0.1 (p < 0.0005). The changes were more pronounced in unstable patients. The transcription factor nuclear factor kappa B (NFκB), which regulates expression of inflammatory mediators, was activated during reperfusion (n = 10, p < 0.0001). Conclusions. Open heart surgery induces an inflammatory response in the human heart, which is more pronounced in patients with unstable angina. It involves NFκB activation and expression of several NFκB-regulated genes.