Objective To explore the possible mechanism of Qutan Tongyang Decoction（ 祛痰通阳汤） in the treatment of chronic heart failure. Methods Ninety male Wistar rats were randomly divided into normal group

model group

captopril group

and low

middle and high dose Chinese medicine groups

with 15 rats in each group.Except for normal group

rats were given intraperitoneal injection of doxorubicin hydrochloride injection to prepare the chronic heart failure rat model. After modeling

captopril group was given captopril tablets 4. 375 mg/（ kg · d） by gavage. Low

middle and high dose Chinese medicine groups were respectively given 1. 8

3. 6 and 7. 2 ml Qutan Tongyang Decoction（ concentration 1. 85 mg/ml） by gavage each day. Normal group and model group were given 3. 6 ml distilled water by gavage

once a day and lasted for 4 weeks. The levels of serum Ang Ⅱ and AT1 mRNA in myocardium in each group were determined. Echocardiography parameters including left ventricular end diastolic diameter（ LVEDD）

stroke volume（ SV） and ejection fraction（ EF） were detected before and after modeling and after administration. Results Compared with normal group

the level of serum Ang Ⅱ and myocardial AT1 mRNA and LVEDD were significantly increased in the model group and the SV and EF were decreased in the model group（ P <0. 01）. Compared with the model group

the levels of serum Ang Ⅱ and myocardial AT1 mRNA and LVEDD in captopril group and middle and high dose Chinese medicine groups were decreased and SV and EF in captopril group and middle and high dose Chinese medicine group were both increased（ P < 0. 05 or P < 0. 01）. Conclusion Qutan Tongyang Decoction could reduce the level of serum Ang Ⅱ in the rats with chronic heart failure

inhibit the expression of AT1 mRNA and improve the cardiac function so that the myocardial remodeling could be improved.