Objective To investigate the effect of Xin’an Granule on cardiac function

serum B-type brain natriuretic peptide（BNP），and cardiac troponin-I（cTnI）on the rats with chronic heart failure（CHF）and their correlations by establishing a rat CHF model. Methods A rat CHF model was prepared

and the model rats were ran⁃domly divided into model control group

Western medicine group

and Xin’an Granule group. In addition

a blank control group was set. The blank control group received no drug intervention; the model control group received intra⁃gastric administration of normal saline; the Western medicine group received intragastric administration of benaz⁃epril and metoprolol

and the Xin’an Granule group received intragastric administration of Xin’an Granules

all for six weeks. The left ventricular end-systolic diameter（LVESD），left ventricular end-diastolic diameter（LVEDD）， left ventricular ejection fraction（LVEF），and serum BNP and cTnI levels of each rat were measured after six weeks. Results Compared with the blank control group

the model control group had significantly increased LVESD

LVEDD

and serum BNP and cTnI levels

and a significantly reduced LVEF（all P ＜ 0.05）. Compared with the model control group

the Western medicine group and Xin’an Granule group had significantly reduced LVESD

LVEDD

and serum BNP and cTnI levels

and a significantly increased LVEF（all P＜0.05）. There were no signifi⁃cant differences in the above parameters between the Xin’an Granule group and the Western medicine group（P>0.05）. Conclusion Xin’an Granule has a positive inotropic effect on experimental rats with CHF

and it can dilate blood vessels

improve myocardial blood supply

increase myocardial hypoxia tolerance

and enhance cardiac function.