Heart failure in children with single ventricle. Level of biochemical markers after fontan procedure with extracardiac conduit

The aim of the study was to assess biochemical markers of myocardial injury, endothelial dysfunction, and heart failure (HF) in children with single ventricle (SV) a year after total cavopulmonary connection (TCPC) and to determine correlations of these biochemical markers with hemodynamic data before TCPC. Materials and Methods. A total of 29 patients with SV aged 3 to 16 years were involved in the study a year after TCPC with extracardiac conduit. The average patient age was 7.7 years ± 3.6 months. Patients were divided into two groups depending on HF (according to NYHA). Group 1 (NYHA I) included 13 patients; group 1 (NYHA II) included 16 patients. All patients underwent complete examination: electrocardiography (ECG), 24-hour Holter ECG monitoring, and echocardiography. Biochemical markers such as brain natriuretic peptide (BNP), N-terminal pro-B-type natriuretic peptide (NT-pro BNP), atrial natriuretic peptide (ANP), fatty acid binding protein (FABP), endothelin-1, and nitric oxide metabolite were assessed. Results. Median NT-pro BNP was elevated in group 2 [123.9 pg/mL (IQR: 52.9-370.5)]. Increased BNP level was observed in 27 children (93.1%) after Fontan procedure. Median BNP levels were elevated in both study groups [204 pg/mL (IQR:129-355) and 211 pg/mL (IQR:92-327), correspondingly]. Median endothelian-1 levels were high in both groups (44.4 (IQR: 14-100.3) and 42.3 (IQR: 6.2-155.8)]. Direct correlation relationship between NT-pro BNP level a year after TCPC and average pulmonary artery pressure before TCPC was found (r=0.54; р=0.04). Nitrogen nitrite level exceeded normal values in all patients. Significantly higher median nitrogen nitrate was found in study group 2 [22.52 (IQR: 31.47-28.95) and 27.94 (IQR: 19.84-45.51), correspondingly], p=0.04. According to the individualized analysis, nitrogen nitrate level corresponded to normal values only in one patient with HF (NYHA II). At the same time, nitrogen nitrite level was elevated in all patients. Conclusions. NT-pro BNP and BNP levels a year after TCPC were elevated in most of the patients with SV (82.8%). The higher pulmonary artery pressure was before TCPC, the higher NT-pro BNP level was a year after the procedure (p=0.04).