Hs-Troponin T Kinetics in Patients Treated With MCO Membranes Compared to High-flux, Low-flux Membranes and HDF

Patients who are on hemodialysis will be included in this study. After obtaining informed consent, patients will be treated with four different hemodialysis sessions:

• Treatment 1: MCO membrane (=medium cut off)
• Treatment 2: low flux membrane
• Treatment 3: high flux membrane
• Treatment 4: HDF(=hemodiafiltration) treatment with high flux membrane The order of the treatment regimens with the different membranes will be randomized in four sequences (Williams design).

Sequence 1: MCO, low flux, HDF, high flux Sequence 2: low flux, high flux, MCO, HDF Sequence 3: high flux, HDF, low flux, MCO Sequence 4: HDF, MCO, high flux, low flux Dialysis treatment will be standardized according to our clinic standard. Dialysis fluid temperature will be set to 1.0°C below the patient's body temperature, which will be assessed by auricular thermometers, to achieve maximal hemodynamic stability. Dialysis fluid composition will be standardized to calcium of 1.25mmol/L, bicarbonate of 30mmol/L, and a variable potassium and sodium concentration, depending on the patients' plasma potassium and sodium concentration.

Ultrafiltration volume will be set according to the caretaking provider.

Membranes used in the study will be FX CorDiax 10, 800 (Fresenius Medical Care, Bad Homburg vor der Höhe, Germany) and Theranova 400 (Baxter, Deerfield, Illinois, USA). We will perform the analysis only in mid-week dialysis due to the following reasons: First, hemodynamic stability is most often compromised during the first treatment of the week, due to the need of large volumes of ultrafiltration and, second, because we assume that troponin T levels reach a steady state 48 hours after the last dialysis session.