System Delay and Mortality in ST-Elevation Myocardial Infarction: A Multicentre, Retrospective, Observational Study in Seoul

Background: Prompt recognition and early management of ST-segment elevation myocardial infarction (STEMI) are crucial for improving outcomes.This study investigates the association between system delay and in-hospital mortality in patients with STEMI.Methods: Using data from the Seoul GOLDEN-time emergency medical system registry, a multicentre retrospective registry in Seoul, this study analysed patients with STEMI who were transported to an emergency department via emergency medical service for cardiac complaints between July 2020 and December 2022.System delay included the response time (first medical contact to an ambulance on the scene), scene time (ambulance on the scene to departure), scene-to-door time (departure to hospital arrival), and door-to-balloon time.Results: Among 654 patients with STEMI who received percutaneous coronary intervention, survivors had shorter overall system delay, prehospital time, scene time, scene-to-door time, and door-to-balloon time than non-survivors.A system delay > 127.5 minutes was associated with high mortality (adjusted odds ratio [aOR], 2.07; 95% confidence interval [CI], 1.05-4.13).Prolonged prehospital time (aOR, 2.35; 95% CI, 1.16-4.95),scene time (aOR, 2.61; 95% CI, 1.24-5.75),and door-to-balloon time (aOR, 2.20; 95% CI, 1.09-4.39)were each independently associated with mortality.Conclusion: Prolonged system delays were associated with increased in-hospital mortality.These findings highlight the need for a comprehensive, system-level approach to reducing system delay across the entire STEMI care pathway.