Aims/Background Acute left ventricular failure (ALVF), a common cardiovascular emergency characterized by rapid occurring and progressing, poses a severe threat to the patient’s life. The purpose of this study is to investigate the impact of combining recombinant human brain natriuretic peptide (rhBNP) with sacubitril valsartan sodium on cardiac function, inflammatory markers, and oxidative stress indicators in elderly ALVF patients. Methods This retrospective study included 167 elderly ALVF patients between June 2022 and June 2024. Based on the treatment regimen, the patients were divided into three groups: a control group (n = 49, who received traditional treatment), an observation group (n = 61, who received replacement treatment with sacubitril and valsartan sodium), and a combination group (n = 57, who administered with a combination of rhBNP and sacubitril and valsartan sodium). Clinical data of patients were accessed from the electronic medical record system in the Second Affiliated Hospital of Nanjing Medical University, and the pre- and post-treatment cardiac function, inflammatory marker levels, oxidative stress indicators, and incidence of adverse reactions were compared among the three groups of patients. Results Following treatment, the left ventricular ejection fraction (LVEF) and superoxide dismutase (SOD) levels were significantly higher in the combination group compared to the observation and control groups. Furthermore, the combination group exhibited a substantial decrease in the left ventricular end-diastolic diameter (LVEDD), creatine kinase isoenzyme MB (CK-MB), alpha hydroxybutyrate dehydrogenase (α-HBDH), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α). Moreover, TNF-α, MDA and interleukin-6 (IL-6) levels were significantly lower in the observation group compared to the control group (p < 0.05). Additionally, no significant difference was observed in the incidence of adverse reactions between the two groups (p > 0.05). Conclusion Combining rhBNP with sacubitril and valsartan sodium can effectively improve the cardiac function among elderly ALVF patients, significantly reducing the levels of inflammatory factors and alleviating oxidative stress reactions. This approach provides superior efficacy and safety for managing elderly ALVF patients.