Background: Most patients with surgically corrected tetralogy of Fallot (TOF) are faced with multiple residua and sequelae such as pulmonary regurgitation (PR), resulting in reoperation for pulmonary valve replacement (PVR). Plasma brain natriuretic peptide (BNP) level and serum N-terminal pro-BNP (NT-pro-BNP) level are useful as diagnostic objective markers of chronic heart failure (CHF). The aim of the study was to examine whether these markers have predictive ability for reoperation in children with surgically corrected TOF.
Methods and results: Fifty-eight patients (38 male, 20 female) aged 1-18 years (median, 7 years) were enrolled. Serum NT-pro-BNP in TOF patients was significantly higher than in age-matched hospital controls without CHF (359.5±449.7pg/ml vs. 86.1±45.1pg/ml, respectively; P<0.0001). BNP and NT-pro-BNP had a better correlation with CHF index, RVEDP, and LVEDV in TOF groups. Children with surgically corrected TOF who had indication for PVR had higher BNP and NT-pro-BNP and more severe PR than those without indication for PVR. On multivariate logistic regression analysis, NT-pro-BNP was the strongest predictor for reoperation in patients with surgically corrected TOF. Area under the curve of NT-pro-BNP for reoperation was 0.950 (P<0.001) with a sensitivity of 88.9% and specificity of 91.8%.
Conclusions: NT-pro-BNP is a good biomarker for monitoring CHF, and is a good predictor of PVR in children with surgically repaired TOF.