Association of epicardial fat with cardiac structure and function and cardiovascular outcomes: A protocol for systematic review and meta-analysis

Background: Epicardial fat represents visceral adiposity. Many observational studies have reported that increased epicardial is associated with adverse metabolic profile, cardiovascular risk factors, and coronary atherosclerosis in patients with cardiovascular diseases and in general population. We and others have previously reported the association of increased epicardial fat with left ventricular (LV) hypertrophy and diastolic dysfunction as well as the development of heart failure (HF) and coronary artery disease in these populations. In some studies, however, the association did not reach statistical significance. The inconsistent results may be due to limited power, different imaging modalities for quantifying epicardial fat volume, and different outcome definitions. Accordingly, we aim to perform the systematic review and meta-analysis of studies on the association of epicardial fat with cardiac structure and function and cardiovascular outcomes. Methods: This systematic review and meta-analysis will include observational studies examining the association of epicardial fat with cardiac structure and function or the cardiovascular outcomes. Relevant studies will be identified by searching electronic databases including PubMed, Web of Science, and Scopus and by manual screening of reference lists of relevant reviews and retrieved studies. The primary outcome will be cardiac structure and function. The secondary outcome will be cardiovascular events including death from cardiovascular causes, hospitalization for HF, nonfatal myocardial infarction, and unstable angina. Discussion: The results of our systematic review and meta-analysis will provide evidence regarding the clinical usefulness of epicardial fat assessment. Systematic review registration: INPLASY 202280109.