Plasma levels of B-type natriuretic peptide in patients with tetralogy of Fallot after surgical repair

Objective: To evaluate the utility of plasma BNP measurement in the long term follow-up of patients with surgically repaired tetralogy of Fallot (TOF). Methods: From 2002 to 2008, plasma BNP concentration was measured in 130 patients with TOF at the age of mean 16.1 +/- 7.1 years and mean 13.0 +/- 6.5 years after surgically repair. BNP levels were compared to age and gender-specific normal values, results of exercise testing, clinical, electrocardiographic, and echocardiographic data. Results: BNP was b200 pg/ml in all and elevated in 60% of patients. Higher values were found in females (p = 0.001), in patients waiting for pulmonary valve replacement (p < 0.001), and in NYHA class II compared to NYHA I patients (p = 0.012) with an inverse correlation between BNP and exercise time (r = -0.59, p < 0.001). BNP was correlated with right ventricular dilatation (r = 0.29, p = 0.005) and severity of both tricuspid (r = 0.22, p = 0.015) and pulmonary regurgitation (r = 0.20, p = 0.029). Longitudinal data revealed increasing BNP levels before (p = 0.04) and a BNP decrease after pulmonary valve replacement (p = 0.03), but no change in patients without surgery. Conclusions: In patients with surgically repaired TOF, plasma BNP is significantly correlated with right ventricular volume load. In clinical practice a considerable overlap limits the estimation of right ventricular volume load by BNP, but longitudinal evaluation helps to appoint the appropriate timing of pulmonary valve replacement. (C) 2009 Elsevier Ireland Ltd. All rights reserved.