text: Plasma concentrations of novel cardiac biomarkers before and after hemodialysis session.
  Biomarkers are useful for establishing disease severity or prognosis in patients with chronic kidney disease. The aim of our study was to determine the plasma concentrations of novel cardiovascular biomarkers in patients on chronic hemodialysis in the context of published upper reference limits (URL) of these biomarkers; and to compare the plasma concentrations of those same analytes before and after hemodialysis session. Plasma concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP), mid-regional pro-A-type natriuretic peptide (MR-proANP), mid-regional pro-adrenomedullin (MR-proADM), C-terminal pro-endothelin-1 (CT-proET-1), C-terminal pro-arginine vasopressin (CT-proAVP, also known as Copeptin) and soluble ST2 (sST2) were measured in 28 patients before and after dialysis session. Of the 28 patients with conventional hemodialysis, 24 had low-flux hemofiltration and 4 had high-flux hemodiafiltration. Median plasma concentrations of the biomarkers obtained before hemodialysis were as follows: NT-proBNP, 11,307ng/L (URL, 500ng/L); MR-proANP, 778pmol/L (URL, 250pmol/L); MR-proADM, 2.57nmol/L (URL, 0.52nmol/L); median CT-proET-1, 252pmol/L (URL, 75pmol/L); median CT-proAVP, 142pmol/L (URL, 19pmol/L); and median sST2, 27ng/mL (URL, 50ng/mL). Median relative analyte changes after low-flux vs. high-flux dialysis compared to predialysis values were +19% vs. -43% for NT-proBNP; +7% vs. -45% for MR-proANP; -2% vs. -63% for MR-proADM; -19% vs. -61% for CT-proET-1; +13% vs. -64% for CT-proAVP; and +2% vs. +3% for sST2. Plasma concentrations of the investigated biomarkers were markedly increased in chronic hemodialysis patients (with the exception of sST2). After hemodialysis session, analyte concentrations (with the exception of sST2) decreased significantly using a high-flux membrane but not if using a low-flux membrane.