Value of N-terminal pro brain natriuretic peptide levels in different types of Fontan circulation

N-terminal pro brain natriuretic peptide (NT-proBNP) is an important biomarker in congestive heart failure. This has also been confirmed in congenital heart disease. However, its clinical value in patients with different types of Fontan circulation remains questionable. We prospectively analysed 124 patients with various types of Fontan surgery between October 2006 and February 2011. We included 49 patients with older Fontan modification [atriopulmonary connection (APC) and atrioventricular connection (AVC)] and 75 patients with total cavopulmonary connection (TCPC). The NT-proBNP levels of patients with APC/AVC were significantly higher than in patients with TCPC (P 0.001), even after accounting for sex, age, ventricular function, atrioventricular regurgitation, ventricular morphology, and arrhythmia (P 0.035). Levels of NT-proBNP positively correlated with atrioventricular valve regurgitation (r 0.29, P 0.013) and ventricular dysfunction (r 0.23, P 0.052) only in patients with TCPC, but not in patients with APC or AVC (r 0.01, P 0.509 and r 0.10, P 0.493, respectively). Levels of NT-pro BNP are related to the type of Fontan circulation. The older types (APC/AVC) that involve more atrial tissue in the systemic venous pathway show higher NT-proBNP levels independently of their cardiac status. Their NT-proBNP levels should be interpreted with care.