Objective To explore the effect of Xiefei Lishui Formula （泻肺利水方） on heart failure. Methods Xiefei Lishui Formula at a concentration of 425

212.5

106.25

53.125

26.5625 mg/ml was given to wild-type AB zebrafish respectively

and the maximum tolerated concentration was determined on the basis of death and toxic reaction after 4.5 hours to screen the concentration used in this study. Zebrafish were put into the 6-hole plate and were divided into high

medium and low dose Xiefei Lishui Formula group

digoxin group

normal group and model group

with 30 zebrafish in each group; the concentration of high

medium and low dose Xiefei Lishui Formula was defined according to the above result; 3μl degoxin at the concentration of 0.1μg/ml was applied; 3 ml fish culture water was put into normal group and model group respectively. The plates were all put in the incubator for four hours

and verapamil was used to establish the zebrafish model of heart failure. After 30 minutes

15 zebrafish in each group were selected out

and cardiac dilatation and venous congestion were measured under dissecting microscope; heart rate was counted in 12 zebrafish

and the cardiac output and blood flow rate were analyzed. Results The maximum tolerated concentration of Xiefei Lishui Formula in zebrafish model of heart failure was 106.25 mg/ml

and therefore

106.25

53.125 and 26.5625 mg/ml were set as the concentration of high

medium and low dose group. There were obvious cardiac enlargement and venous congestion in zebrafish of model group

and the cardiac output

blood flow rate and heart rate decreased having significantly statistical differences compared to those of normal group（P<0.01）. Compared to model group

high dose Xiefei Lishui Formula group and degoxin group had smaller areas of cardiac dilatation and venous congestio; high

medium and low dose Xiefei Lishui Formula groups and degoxin group had increased cardiac output

blood flow rate and heart rate（P<0.05 or P<0.01）. Conclusion Xiefei Lishui Formula can improve the cardiac function in zebrafish model of verapamil-induced heart failure

and the concentration of 106.25 mg/ml works best.