At time of visit for RHC, all blood samples except for SvO2 (obtained during RHC) and PaCO2 (arterial or capillary blood gas analysis) were obtained by venipuncture of a peripheral vein during routine clinical and diagnostic workup. All samples were analysed immediately. For fibrinogen assessment, blood was drawn into standardised 3.1% (v/v) trisodium citrate tubes at a final citrate to blood ratio of 1:10 according to manufacturer's instruction (Sarstedt, Nümbrecht, Germany) and processed using a fully automated haemostasis analyser (BCS XP, Siemens Healthcare, Erlangen, Germany) with the Multifibren U reagent kit (Siemens Healthcare, Erlangen, Germany). Reference values for fibrinogen plasma concentrations within this study were 1.8–3.5 g/l.