Objective To investigate the possible mechanism of Shenlian Fumai Granule on heart failure and arrhythmia. Methods A total of 48 C57 BL/6 J mice were randomly divided into a sham operation group

a model group

a Chinese medicine group and a western medicine group

with 12 rats in each group. Except for the sham operation group

heart failure mice were established by narrowing thoracic aorta. After 3 days

the Chinese medicine group was given Shenlian Fumai Granule 0. 23 g/（ 25 g·d）

and the western medicine group was given amiodarone8 mg/（ 25 g·d）. The sham operation group and the model group were given normal saline 20 ml/（ kg·d） by gavage for 4 weeks. The cardiac function and incidence of arrhythmia were detected in each group. The cardiomyocytes were isolated and the sodium current was recorded. The expression of SCN5 A gene and protein in sodium channel was detected by western blot and polymerase chain reaction（ PCR）. Results Compared with the sham operation group

the cardiac ejection fraction and short-axis contraction rate of the model group were significantly decreased

and the peak sodium current was decreased. The proportion of premature beat mice

late sodium current

late sodium current/peak sodium current value and sodium channel SCN5 A gene and protein expression were increased（ P < 0. 05 or P <0. 01）. Compared with the model group

the cardiac ejection fraction

short-axis contraction rate and peak sodium current of the rats in the Chinese medicine group were significantly increased. The cardiac ejection fraction and late sodium current in the western medicine group were significantly increased. The proportion of the premature beat mice and the expression of SCN5 A gene and protein in the Chinese medicine group and the western medicine group were decreased significantly

and the late sodium current and late sodium current/peak sodium current value of the Chinese medicine group decreased significantly（ P < 0. 05 or P < 0. 01）. Compared with the western medicine group

the cardiac ejection fraction

short-axis contraction rate and peak sodium current of the Chinese medicine group were significantly increased

and the late sodium current and late sodium current/peak sodium current value decreased（ P <0. 01）. Conclusion Shenlian Fumai Granule can inhibit the expression of sodium channel in cardiomyocytes and improve the sodium current of cardiomyocytes

thus inhibiting the occurrence of heart failure arrhythmia.