Myocardial tissue expression of mRNA and preoperative neutrophil-lymphocyte ratio in children undergoing congenital heart surgery

Figure 1. Flowchart for selecting the 20 patients included in the final analysis. CHD, congenital heart disease; ToF, tetralogy of Fallot; SaO2, oxygen saturation; VSD, ventricular septal defect; PH, pulmonary hypertension.

Figure 2. Linear regression plot adjusted for NLR and SaO2 with r=−0.44 (P=0.002). Black dots: represent patients with tetralogy of Fallot. Red dots: represent patients with ventricular septal defects. NLR, neutrophil-lymphocyte ratio; SaO2, oxygen saturation.

Figure 3. Myocardial tissue expression of TNF-α mRNA, IL-1β mRNA, IL-6 mRNA and IL-10 mRNA analyzed in the myocardium of the right atrium before cardiopulmonary bypass in children with ToF (black bar) and ventricular septal defect (white bar). The bars express the intensity of the mRNA. §, P=0.79; ^, P=0.76; ¶, P=0.21; *, P=0.03. mRNA, messenger RNA; VSD, ventricular septal defect; ToF, tetralogy of Fallot.

Figure 4. A negative correlation between IL-10 mRNA and NLR (r=−0.27; P=0.14). mRNA, messenger RNA; NLR, neutrophil-lymphocyte ratio.

Figure 5. A positive correlation between SaO2 and the IL-10 mRNA (r=0.40; P=0.07). SaO2, oxygen saturation; mRNA, messenger RNA.

Figure 6. Schematic representation of the probable mechanism of preoperative NLR regulation in ischemic patients undergoing surgical repair. We used a model patient with tetralogy of Fallot and the results of the present study. Ischemia induces a systemic stress involving the myocardium and endothelium of these patients. This stress, in turn, activates the inflammation cascade that was possible to perceive by the expression of TNF-α, IL-1β, IL-6 mRNAs, which in turn stimulates the synthesis of neutrophils, increasing their concentration. On the other hand, there is a low expression of IL-10 mRNA, and this inhibits the synthesis of lymphocytes, decreasing their concentration. All of this leads to an imbalance in the neutrophil-lymphocyte ratio, leaving the patient in a condition of chronic inflammation, which can be easily seen in a simple preoperative blood count. This patient, when subjected to surgical stress associated with the use of CPB, contact with a non-endothelial surface, generates a physiological inflammatory response, but which in these patients can be exacerbated. The exacerbated inflammatory response causes tissue injury in the heart (negative inotropism), lung (respiratory…