Importance of the 'area under the curve' from serial NT-proBNP measurements during treatment with sacubitril/valsartan

Aims Serial assessment of natriuretic peptides is widely utilized in heart failure clinics. Uncertainty exists regarding the value of multiple natriuretic peptide measurements and how they might be best interpreted. Methods and results Six hundred thirty-two patients with heart failure with reduced ejection fraction (<40%) and complete biomarker data were enrolled to receive sacubitril/valsartan. Patients underwent periodic study visits during 1-year followups. Echocardiographic data and cardiac biomarkers, including N-terminal pro-B-type natriuretic peptide (NT-proBNP) were collected during study visits. Patients were categorized into three groups based on tertiles of baseline NT-proBNP levels. The area under the curve (AUC) of NT-proBNP measurements across study visits was calculated. Compared with patients with higher AUC (and thus higher concentrations over a longer period of time), those with lower AUC were younger, had a lower prevalence of chronic kidney disease, prior coronary artery bypass graft, atrial fibrillation, and higher body-mass index. A significant interaction existed between baseline NT-proBNP and subsequent AUC for predicting LVEF change across visits (Pvalue < 0.001): among those with lower baseline NT-proBNP, similar improvements in left ventricular (LV) volumes LV ejection fraction, and LV mass index were observed across subsequent AUC (P-value > 0.1). However, among those with higher baseline NT-proBNP, those with lower subsequent AUC had a greater improvement in cardiac remodelling indices (P-value < 0.05). Conclusions Serial NT-proBNP monitoring (integrating the totality of measurements as an AUC) during treatment with sacubitril/valsartan informs unique information regarding the future changes in cardiac remodelling indices, especially among those with higher NT-proBNP levels at baseline.