Objective To investigate the efficacy of lyophilized recombinant human brain natriuretic peptide (rhBNP) assisted non-invasive positive pressure ventilation (NIPPV) in the treatment of elderly heart failure and its effects on arterial blood gas analysis and cardiac function.Methods A total of 98 elderly patients with heart failure admitted to Pingxiang People's Hospital from June 2020 to April 2023 were selected and randomly divided into the control group and the observation group using a random number table method, with 49 cases in each group. The control group was treated with NIPPV alone, while the observation group was treated with NIPPV combined with lyophilized rhBNP. The total effective rate of treatment, arterial blood gas indicators [arterial oxygen saturation (SaO₂), partial pressure of arterial oxygen (PaO₂), pH, partial pressure of arterial carbon dioxide (PaCO₂)], cardiac function indicators [strike volume (SV), cardiac index (CI), left ventricular ejection fraction (LVEF), left ventricular end-systolic diameter (LVESD), N-terminal pro-brain natriuretic peptide (NT-proBNP)], and incidence of adverse reactions between the two groups were compared.Results The total effective rate of the observation group was higher than that of the control group (P＜0.05); After treatment, the levels of PaO₂, pH, and SaO₂ in the observation group were higher than those in the control group, while the level of PaCO₂ was lower than that in the control group (P＜0.05); After treatment, the LVEF, SV, and CI of the observation group were higher than those of the control group, while LVESD and NT-proBNP were lower than those of the control group (P＜0.05); There was no statistically significant difference in the incidence of adverse reactions between the two groups (P＞0.05).Conclusion The clinical efficacy of lyophilized rhBNP combined with NIPPV in the treatment of elderly heart failure is significant, which can improve blood gas indicators, reduce cardiac load, improve cardiac function, is safe and reliable, and is worthy of clinical promotion.