OBJECTIVE To research and analyze the hemodynamic status of refractory septic shock associated cardiac dysfunction. METHODS 70 refractory septic shock patients were studied. In the duration of pulmonary artery catheter (PAC)-directed hemodynamic optimization, the patients were divided into a cardiac dysfunction group and a control group. Hemodynamic parameters, arterial blood lactate concentration and APACHE II scores were obtained instantly after the placement of a PAC, then lactate clearance in 24 hours was surveyed and calculated. Subsequently the two groups of patients were regrouped by nonsurvivor and survivors respectively. All the obtained values were analyzed with statistic methods. RESULTS 37% of the refractory septic shock patients was complicated with cardiac dysfunction. The age of the patients complicated with cardiac dysfunction was significantly higher than that of the patients of the control group. Central venous pressure (CVP), pulmonary artery obstruction pressure (PAOP), pulmonary artery pressure (PAP), systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI) and oxygen extraction ratio (O2ext) in the cardiac dysfunction group were significantly different from those in the control group. Cardiac output (CO), cardiac index (CI), oxygen delivery index (DO2I) and mixed venous oxygen saturation (SvO2) were significantly lower than those of the patients in the control group. SvO2 had a strong correlation with CI. If the patients were regrouped by nonsurvivors and survivors, in the patients complicated with cardiac dysfunction APACHE II scores were significantly higher in the nonsurvivors than survivors; the lactate clearance in 24 hours (median--25%) of the nonsurvivors was significantly lower than that of nonresponders (median 22%), P < 0.05. Conclusion (1) In refractory septic shock patients, cardiac dysfunction maybe the main reason leading to bad outcome. (2) Higher CVP and PAOP and lower SvO2 indicate the onset of cardiac dysfunction. (3) The patients with significantly high initial arterial blood lactate level and the low lactate clearance in 24 hours had bad outcome.