RecruitingDrug trialRetrospective Analysis of the Effect of In-hospital Initiation of PCSK9i on Clinical Outcomes in Chinese ACS PatientsThe objective of this study is to investigate the effectiveness of in-hospital initiation of alirocumab combined with statin ± ezetimibe on major cardiovascular events (MACE) in Chinese ACS patients. The main question it aims to answer is: whether early initiation PCKS9i in hospital could reduce recent cardiovascular event risk in Chinese ACS patients in real-world setting. Data from CCA Database-Chest Pain Center were screened for all ACS patients from 01-Jan 2021 to 31-Dec 2023. Patients diagnosed with STEMI, NSTEMI or UA at admission were identified at the first step. Then, for intervention group, patients who received alirocumab 75mg combined with statin ± ezetimibe during the ACS hospitalization (including the discharge date) will be included; for control group, patients who received statin ± ezetimibe during the ACS hospitalization will be included. All enrolled patients were required to have at least one documented follow-up visit.