Heart and kidney function are heavily intertwined, and once both organs are affected, the patient's prognosis worsens dramatically [1–3]. Natriuretic peptides (NP) (brain natriuretic peptide [BNP] and amino-terminal pro-BNP [NT-proBNP]) are established diagnostic and prognostic biomarkers in the whole spectrum of heart failure (HF) syndromes [4]. However, patients with kidney disease typically have higher NP concentrations [5,6]. Even though the mechanisms seem multifactorial, the possible reliance of NP on renal clearance has motivated some discussion about their clinical utility in patients with severely reduced glomerular filtration rate (eGFR) [7,8].
