Utility of biomarkers in adult Fontan patients with decompensated heart failure

Background: The incidence of heart failure is increasing within the Fontan population. The use of serological markers, including B-type natriuretic peptide, has been limited in this patient population. Methods: This was a single-centre retrospective study of Fontan patients in acute decompensated heart failure. Fontan patients underwent a 1:2 match with non-Fontan patients for each heart failure hospitalisation for comparative analysis. A univariate logistic regression model was used to assess associations between laboratory and echocardiographic markers and a prolonged length of stay of 7 days or greater. Results: B-type natriuretic peptide levels were significantly lower in Fontan patients admitted for heart failure than that in non-Fontan patients [390.9 (+/- 378.7) pg/ml versus 1245.6 (+/- 1160.7) pg/ml, respectively, p < 0.0001] and were higher in Fontan patients with systemic ventricular systolic or diastolic dysfunction than that in Fontan patients with normal systemic ventricular function [833.6 (+/- 1547.2) pg/ml versus 138.6 (+/- 134.0) pg/ml, p = 0.017]. The change from the last known outpatient value was smaller in Fontan patients in comparison with non-Fontan patients [65.7 (+/- 185.7) pg/ml versus 1638.0 (+/- 1444.7) pg/ml, respectively, p < 0.0001]. Low haemoglobin and high blood urea nitrogen levels were associated with a prolonged length of stay. Conclusion: B-type natriuretic peptide levels do not accurately reflect decompensated heart failure in Fontan patients when compared to non-Fontan heart failure patients and should, therefore, be used with caution in this patient population.