NT-proBNP and exercise capacity in adult patients with congenital heart disease and a prosthetic valve: A multicentre PROSTAVA study

Objectives N-terminal B-type natriuretic peptide (NT-proBNP) is an important biomarker for the detection of heart failure. Adults with congenital heart disease (ACHD) and a prosthetic heart valve are at risk for heart failure. This study aimed to determine the value of NT-proBNP in ACHD patients with a prosthetic valve and investigate its relationship with cardiac function and exercise capacity. Methods In this multi-centre cross-sectional observational study, data regarding medical history, echocardiography, exercise testing (VO₂peak) and laboratory blood evaluation (including NT-proBNP) were collected in ACHD patients with a single prosthetic valve (either homografts, heterografts or mechanical valves). Results A total of 306 ACHD patients with pulmonary valve replacement (PVR, n = 139), aortic valve replacement (n = 141), mitral valve replacement (n = 21) or tricuspid valve replacement (n = 5) were investigated. The majority of patients (77 %) were in NYHA class I or II. Elevated NT-proBNP levels (cut-off ≥125 pg/ml) were found in 50 % of the patients, with the highest levels in patients with mitral valve replacements. In this study population, NT-proBNP levels were associated with gender (p = 0.029) and VO₂max (p < 0.001). In PVR patients, NT-proBNP levels were associated with lower VO₂peak, also after adjustment for age, gender and age at valve replacement in a multivariate model (p = 0.015). Conclusions In patients with ACHD and a prosthetic valve, elevated NT-proBNP levels are frequently observed despite preserved NYHA class. In PVR patients, a higher NT-proBNP level was associated with a lower VO₂peak. These results may be of importance in the ongoing discussion about the timing of valve replacement in patients with CHD.