Abstract Background and Aims The recent Emmy trial underscored notable improvements in cardiac structure and function among post-acute myocardial infarction (AMI) patients treated with Empagliflozin, compared to those receiving a placebo. However, limitations such as a small sample size and a short follow-up period hindered the assessment of potential differences in actual clinical events between the groups. Consequently, our study aimed to evaluate the long-term outcomes, survival rates, rates of major adverse cardiovascular events (MACE), and heart failure (HF) incidence in patients with preserved ejection fraction (EF) who experienced AMI and underwent successful percutaneous coronary intervention (PCI), comparing those who received early initiation of Dapagliflozin with those who did not. Methods Data from the Taipei Medical University Research Database in Taiwan identified 7,081 inpatients who met the criteria of AMI status post successful PCI, with a left ventricular ejection fraction (LVEF) greater than 50% and absence of clinical symptoms indicative of heart failure. Exclusion criteria included individuals with a pre-existing diagnosis of heart failure before the index AMI episode and those with an LVEF below 50%, resulting in the exclusion of 357 patients from our study. The study subjects were then divided into two groups: those treated with Dapagliflozin and those not treated with Dapagliflozin, with matching for age, diabetes mellitus, and chronic kidney disease in a 1:2 ratio. Results The cohort study included of 756 patients who met the criteria of this study, among whom 252 were Dapagliflozin users and 504 were not. Over a 7-year follow-up period, Kaplan-Meier survival analyses revealed a significant reduction in cardiovascular mortality and all-cause mortality among Dapagliflozin users compared to non-users (p < 0.01). However, no significant differences were observed in heart failure, recurrent AMI, or stroke during the follow-up. Multivariate Cox analysis indicated the use of Dapagliflozin (hazard ratio = 0.310, 95% confidence interval = 0.188-0.510, p < 0.001) and age of diagnosis (hazard ratio = 1.063, 95% confidence interval =1.045-1.081, p < 0.001) were both independent predictors of all cause death. Conclusions In patients with stabilized AMI, the use of Dapagliflozin was associated with a decreased risk of all-cause death, especially cardiovascular mortality. However, there were no significant differences observed in the rates of heart failure, recurrent AMI, or stroke over the seven-year follow-up period.Baseline characteristicsKaplan–Meier curves of all cause death