Background and Aims: The goal for volume replacement therapy is to maintain stable haemodynamics after cardiac surgery. We hypothesized that a short term infusion of hydroxyethyl starch results in better haemodynamic response than an infusion of lower molecular weight gelatin. Material and Methods: 45 patients received a predetermined fixed dose of 15 ml kg −1 of either 4% succinylated gelatin (GEL) or 6% hydroxyethyl starch (HES) or 4% human albumin (HA) after cardiac surgery. Results and Conclusions: Pulmonary capillary wedge pressure was more increased in GEL and HES groups [mean (SD) 153% (54) and 168% (57) of pre-infusion value] than in HA group [122% (23)] (P = 0.031) after completion of infusion, but no differences in cardiac index (CI) and stroke volume index (SVI) were observed. At 2 and 18 hours after end of study infusions SVI was more increased in HES [143% (38) and 148% (41) of pre-infusion values] and HA [143% (35) and 163% (42) of pre-infusion values] groups than in GEL [116% (23) and 125% (30)] group (P = 0.047 at 2 hours and P = 0.033 at 18 hours). In early postoperative phase after cardiac surgery, HES and HA infusions improve haemodynamics more and longer period than GEL infusion.