Objective:To observe the effects of self-designed Yiqi Huoxue Huayu Decoction on cardiac function and serum endothelin (ET-1) and matrix metalloproteinase-9 (MMP-9) levels in patients with chronic heart failure (GHF) complicated with atrial fibrillation.Methods:A total of 100 patients with GHF complicated with atrial fibrillation treated in our hospital from January 2019 to June 2021 were selected as the study subjects, and divided into experimental group and control group according to random number table method, with 50 patients in each group. Patients in both groups were given cardiotonic, diuretic, vasodilator and other conventional treatment, and patients in the experimental group added self-designed Yiqi Huoxue Huayu Decoction. TCM syndrome score, left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD) and left ventricular ejection fraction (LVEF), serum ET-1 and MMP-9 levels, clinical efficacy, safety and incidence of adverse reactions were observed and compared between 2 groups before and after treatment.Results:The total response rate was 82.0% (41/50) in the observation group and 62.0% (31/50) in the control group, and the difference was statistically significant ( χ 2=4.96, P=0.026). After treatment, the symptoms scores of palpitation, shortness of breath, fatigue, chest and hypochasm pain in the observation group were significantly significantly lower than those in the control group ( t=5.28, 5.29, 5.62, 5.42, P<0.01). After treatment, the LVEDD[(51.23±6.59)mm vs. (55.65±6.17)mm, t=3.46], LVESD[(43.10±4.76)mm vs. (45.99±5.31)mm, t=2.87], serum ET-1[(65.79±8.29)μg/L vs. (79.83±10.08)μg/L, t=7.61], MMP-9 [(175.86±24.81)ng/L vs. (189.49±26.13)ng/L, t=2.68] in experimental group were significantly lower than those in the control group ( P<0.05), while LVEF [(50.01±7.6)% vs. (46.25±6.96)%, t=2.57] was significantly higher than that of the control group ( P<0.05). There were no significant differences in GPT, GOT, UA, SCr levels between both groups before and after treatment ( P>0.05). There were no obvious adverse reactions betewwn both groups. Conclusion:The self-designed Yiqi Huoxue Huayu Decoction can relieve the clinical symptoms, improve the heart function and serum ET-1 and MMP-9 levels in patients with GHF complicated with atrial fibrillation safely.