B-Type Natriuretic Peptide Levels in Patients with Functionally Univentricular Hearts After Total Cavopulmonary Connection

AIMS: To assess plasma B-type natriuretic peptide (BNP) levels in patients with univentricular hearts late after volume unloading by total cavopulmonary connection (TCPC). METHODS: Plasma BNP was measured by sandwich immunoassay in 67 patients after a modified Fontan procedure. BNP levels were compared with age and sex-specific normal values, clinical and echocardiographic data, and results of exercise testing. RESULTS: BNP had a wide range of 5-290 pg/ml, but was normal in 81% of patients, and median BNP was only 13 pg/ml. There was no difference between males and females, between patients with left or right ventricular morphology, and no correlation was found between BNP and age, post-operative follow-up period, maximum exercise capability, peak oxygen uptake, or blood oxygen saturation. New York Heart Association class I patients had lower BNP than class II patients (p=0.04). Plasma BNP concentration was positively correlated to the number of specific sequelae (r=0.59, p<0.001), and to severity of atrioventricular regurgitation (r=0.38, p=0.002). 5/13 patients with elevated BNP died during follow-up. CONCLUSION: BNP plasma concentration was normal in the majority of patients up to 15 years after TCPC. Elevated and increasing BNP levels were associated with increased morbidity and late mortality.