Epicardial Adipose Tissue in Heart Failure Phenotypes - A Meta-Analysis.

Background: Epicardial adipose tissue (EAT) is increased in comorbidities common in heart failure (HF). In this sense, EAT could potentially mediate effects that lead to an impaired cardiac function.

Objectives: This meta-analysis aims to investigate if the amount of EAT in all-types of HF and each HF phenotype is significantly different from control patients.

Methods: This meta-analysis followed the Meta-analysis Of Observational Studies in Epidemiology guidelines. The search was performed in the MEDLINE, Embase, and Lilacs databases until November 2020. Two authors performed screening, data extraction, and quality assessment. A p-value <0.05 was defined as statistically significant.

Results: Eight observational studies were included, comprehending 1,248 patients in total, from which 574 were controls, 415 had HF with reduced ejection fraction (HFrEF) and 259 had HF with mid-range or preserved ejection fraction (HFmrEF or HFpEF). The amount of EAT was not different between all types of HF and the control group (SMD = -0.66, 95% CI: -1.54 to 0.23, p =0.14). Analyzing each HF phenotype separately, patients with HFrEF had a reduced EAT when compared to the controls (SMD= -1.27, 95% CI: - 1.87 to -0.67, p <0.0001), while patients with HFmrEF or HFpEF showed an increased EAT when compared to controls (SMD= 1.24, 95% CI: 0.99 to 1.50, p <0.0001).

Conclusion: The amount of EAT was not significantly different between all types of HF and the control group. In patients with HFrEF, the EAT volume was reduced, whereas in HFpEF and HFmrEF, the amount of EAT was significantly increased. PROSPERO registration number: CRD42019134441.