Recombinant human brain natriuretic peptide(Shijiazhuang Wotai Biological Technology Co., Ltd.)

1. Main purpose: To evaluate the difference in efficacy of the trial group (randomly assigned to receive lyophilized recombinant human brain natriuretic peptide) compared with the placebo control group in AHF patients, using the proportion of subjects with improved dyspnea within 24 hours as the evaluation index. 2. Key secondary purpose: To evaluate the efficacy of the trial group (randomly assigned to receive lyophilized recombinant human brain natriuretic peptide) compared with the placebo control group in AHF patients. 3. Secondary purpose: 1. To evaluate the efficacy of the trial group (randomly assigned to receive lyophilized recombinant human brain natriuretic peptide) compared with the placebo control group in AHF patients. 2. To explore the changes in natriuretic peptide levels after administration in the trial group (randomly assigned to receive lyophilized recombinant human brain natriuretic peptide) and the placebo control group. 3. To evaluate the safety of all AHF patients treated with lyophilized recombinant human brain natriuretic peptide. To evaluate the safety of all AHF patients treated with placebo.