Objective:At present, emergency acute heart failure unit has been gradually carried out in China. This study is to analyze the impact of acute heart failure unit on the mortality and readmission rate of acute heart failure (AHF) within 6 months after discharge.Methods:Patients with AHF admitted to Emergency Department and Department of Cardiology, Peking University People's Hospital between December 2019 and December 2020, were prospectively collected. Patients with complicated malignant tumor, stage 4-5 chronic kidney disease, automatic discharge, and incomplete medical history were excluded. The baseline data, past medical history, admission condition, and auxiliary examination were collected. After discharge, the information of oral drugs, hospital readmission and death were collected through outpatient medical records in clinical data center or telephone consultation. Patients were divided into the emergency acute heart failure unit treatment group (emergency AHFU group), emergency routine treatment group (outside AHFU group) and cardiology treatment group according to the different treatment locations. SPSS 25.0 software was used for comparison between groups, and a P<0.05 was considered as statistically significant. ResuIts:A total of 238 patients with AHF were enrolled, 28 patients died in hospital, and 210 patients were followed up. Four cases were excluded from malignant tumor during follow-up, and 6 cases were lost to follow-up. There were 40 cases in the emergency AHFU group, 67 cases in the outside AHFU group, and 93 cases in the cardiology treatment group. According to the prognosis, the patients were divided into the poor prognosis group ( n=83) and good prognosis group ( n=145). The age, sex, vital signs and cardiac function of patients in the emergency AHFU group were basically the same as those in the outside AHFU group at admission, and the proportion of patients in the emergency AHFU group using non-invasive positive pressure ventilation was higher (52.5% vs. 32.8%, P<0.05). The utilization rate of angiotensin converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor enkephalinase inhibitors, β-blockers, diuretics and other oral drugs was higher in the emergency AHFU group after discharge, and patients also had more regular follow-up (95% vs. 79.1%, P<0.05). The 6-month readmission rate (15.0% vs. 40.3%, P<0.05) and the 6-month readmission and mortality composite results of patients in the emergency AHFU group (17.5% vs. 43.3%, P<0.05) were significantly lower than those in the outside AHFU group. COX regression analysis showed that the readmission rate of patients in the emergency AHFU group was lower than that in the outside AHFU group ( OR=2.882, 95% CI:1.267~6.611, P=0.12). Compared with the cardiology treatment group, the AHFU group had higher systolic blood pressure, faster heart rate, NT-probNP level, higher proportion of NYHA grade Ⅳ and Killip grade Ⅲ cardiac function (all P<0.05). The proportion of non-invasive mechanical ventilation in the AHFU group was significantly higher than that in the cardiology treatment group (52.5% vs. 30.1%, P<0.05). After discharge, there were no significant differences between angiotensin converting enzyme inhibitor/angiotensin receptor blocker/angiotensin receptor enkephalinase inhibitors and β-blockers. There were also no significant differences in readmission and mortality rate 6 months after discharge. Binary logistics regression analysis found that the independent risk factors of AHF were routine emergency treatment, age, female sex, coronary heart disease, and BUN peak. Conclusions:The emergency acute heart failure unit is an independent protective factor for acute heart failure and reduced readmission rates within 6 months and readmission and mortality composite outcomes. Older age, female sex, coronary heart disease and elevated BUN peak are independent risk factors affecting the prognosis of AHF, which should be identified and preventive measures should be taken early.