Epicardial adipose tissue in diabetic myocardial disorder: Role of echocardiography

Table 1 Role of epicardial adipose tissue

Physiologic	Pathophysiologic
Thermogenic brown fat-like function	Endocrine, paracrine, and vasocrine secretion of proinflammatory and profibrotic cytokines
Protective (e.g., mechanical protection in the case of physical trauma)	Local inflammation, disrupted adipogenesis
Source of energy in case of metabolic demand	Acceleration of atherosclerosis
Storage compartment providing the myocardium with free fatty acids	Decreased insulin sensitivity of the adipocytes
Buffer preventing excess fatty acid influx	Ventricular dysfunction (Diabetic pericardial disorder)

Table 2 Advantages and limitations of echocardiographic (i.e., ultrasound) epicardial adipose tissue thickness measurement

Advantages	Limitations
Non-invasive, easily done, cost-effective	No regional EAT measurement (e.g., atrial EAT)
Very little time consuming	Interobserver variability (especially in unexperienced investigators)
Simultaneous assessment of cardiac function	Non-ideal acoustic window
Reproducible	The lack of a reference range
Readily available for frequent follow-up	No volumetric assessment
Direct measure of visceral adiposity (rather than anthropometric measure)	No assessment of intramyocardial adiposity
Non-harmful	No EAT attenuation assessment (e.g., inflammation)

EAT: Epicardial adipose tissue.

Table 3 Association of epicardial adipose tissue accumulation with cardiovascular disease (heart failure with preserved ejection fraction, coronary artery disease, atrial fibrillation)

Imaging method for EAT assessment	CVD and related references
ECHO	HFpEF[12,53,54,58], CAD[24,62], AF[52,91]
CT	HFpEF[6], CAD[34-40,89,93], AF[18,52,91,92]
CMR	HFpEF[32,33,43,59,88,90], CAD[24,32] AF[43,52,91]

AF: Atrial fibrillation; CAD: Coronary artery disease; CMR: Cardiac magnetic resonance; CVD: Cardiovascular disease; CT: Computed tomography; EAT: Epicardial adipose tissue; ECHO: Echocardiography; HFpEF: Heart failure with preserved ejection fraction.