Abstract
Abstract Background The role of Epicardial adipose tissue (EAT) in the acute phase of ST-segment elevation myocardial infarction (STEMI) seems unclear and controversial. Cardiac magnetic resonance (CMR) imaging can quantify the extracellular volume (ECV) in specific regions of interest. This study was to explore the relationship between EAT and ECV in different regions and its impact on the prognosis of STEMI patients. Methods This retrospective study included 437 patients diagnosed with acute STEMI. The median time to complete CMR was 5 (4, 6) days after hospitalization. Global ECV, ECV in the non-myocardial infarction region (NMI-ECV), and ECV in the myocardial infarction region (MI-ECV) were derived from CMR. Results In all patients with STEMI, EATi showed a moderate correlation with Global ECV (r = 0.427, P < 0.001), and NMI-ECV (r = 0.577, P < 0.001), while there was no significant correlation with MI-ECV, LGE%, GLS, and MVO%. In patients with diabetes mellitus, EATi was moderately correlated with Global ECV (r = 0.586; P < 0.001), strongly correlated with NMI-ECV (r = 0.743; P < 0.001). The Kaplan–Meier curve demonstrated that patients with high EATi, Global ECV, NMI-ECV, or MI-ECV had a significantly higher long-term risk of MACE (P < 0.05). Conclusions During the acute phase of STEMI, there is a significant correlation between EAT and both Global ECV and NMI-ECV, especially in patients with diabetes. However, there is no significant correlation between EAT and MI-ECV. EAT and ECV in different regions may contribute to exploratory risk stratification of MACE in STEMI patients.