Objective: To investigate the efficacy of sacubitril valsartan sodium in the treatment of patients with coronary heart disease (CHD) complicated with heart failure with mid-range ejection fraction (HFmrEF) and the influence on myocardial energy metabolism. Methods: Eighty patients with CHD who were treated from January 2023 to April 2025 were divided into observation group and control group by random number table method, with 40 cases in each group. The control group was given conventional treatment, while the observation group was treated with sacubitril valsartan sodium. The myocardial energy metabolism indexes [free fatty acid (FFA), myocardial energy expenditure (MEE)], cardiac function indexes [left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF)], N-terminal pro-brain natriuretic peptide (NT-proBNP) and adverse reactions were compared between the two groups. Results: After treatment, FFA, MEE, LVEDD, LVESD and NT-proBNP in the two groups were decreased, and the indexes were lower in observation group (P<0.05). LVEF was increased, and the index in observation group was higher (P<0.05). The incidence rates of adverse reactions revealed no statistical differences between both groups (P>0.05). Conclusion: Sacubitril valsartan sodium can improve myocardial energy metabolism and cardiac function in the treatment patients with CHD and HFmrEF, and it is safe and effective.