Epicardial Adipose Tissue is Associated with Geometry Alteration and Diastolic Dysfunction in Prediabetic Cardiomyopathy

Abstract Background Diastolic dysfunction and alterations in cardiac geometry are early indicators of diabetic cardiomyopathy. However, the association between cardiac changes across the glucose continuum and the contribution of epicardial adipose tissue (EAT) to these changes has not yet been investigated. Purpose In this study, we aimed to investigate the EAT on cardiac diastolic function and structural alterations along the diabetic continuum using cardiac magnetic resonance imaging (CMRI). Methods We enrolled individuals who were categorized into groups based on glucose tolerance status. Left ventricular structure and diastolic function were assessed using echocardiography and CMRI to determine the EAT, intramyocardial fat, and associated parameters. Multivariable logistic regression models were also used. Results In a study of 370 patients (209 normal glucose tolerance, 82 prediabetes, 79 diabetes), those with prediabetes and diabetes showed increased heart dimensions and diastolic dysfunction, including the ratio of early mitral inflow velocity to mitral annular early diastolic velocity (7.9 ± 0.51 vs 8.5 ± 0.64 vs 10.0 ± 0.93, P = .010), left atrial volume index (28.21 ± 14.7 vs 33.2 ± 12.8 vs 37.4 ± 8.2 mL/m2, P < .001), and left ventricular peak filling rate (4.46 ± 1.75 vs 3.61 ± 1.55 vs 3.20 ± 1.30 mL/s, P < .001). EAT significantly increased in prediabetes and diabetes (26.3 ± 1.16 vs 31.3 ± 1.83 vs 33.9 ± 1.9 gm, P = .001), while intramyocardial fat did not differ significantly. Prediabetes altered heart geometry but not diastolic function (odds ratio [OR] 1.22 [1.02-1.83], P = .012; and 1.70 [0.79-3.68], P = .135). Diabetes significantly affected both heart structure and diastolic function (OR 1.42 [1.11-1.97], P = .032; and 2.56 [1.03-5.40], P = .034) after adjusting for covariates. Conclusion Elevated EAT was observed in patients with prediabetes and is associated with adverse alterations in cardiac structure and diastolic function, potentially serving as an underlying mechanism for the early onset of diabetic cardiomyopathy.