Epicardial adipose tissue (EAT) is a fancy term for fatty tissue surrounding the heart. Normally, EAT plays an important role in heart function and offers protective factors for good health.1 In abnormal conditions, EAT is a risk factor for cardiometabolic diseases like obesity and insulin resistance.2 Finding a balance of this heart fat is important for cardiometabolic health.
A closer look at EAT
The beneficial effects of EAT begin before birth.1 EAT acts as a source of energy for the heart, helps regulate blood flow, and protects the heart from various forms of damage, like excessive inflammatory responses.1,2 As we age, our EAT undergoes structural changes that alter some of its activities. However, it still maintains its protective features.2
Traditionally, obesity had been the focus of research concerning cardiometabolic diseases. Still, as new information became available, scientists began studying fatty tissues specific to different organs. EAT is a unique type of fatty tissue that can exert regional and systemic cardiometabolic effects depending on its heart-related location1 leading to increased interest in EAT research.
Epicardial adipose tissue is implicated in the development of chronic diseases like
- atrial fibrillation,
- heart failure,
- and coronary artery disease.1
The processes by which EAT is involved in these conditions are complex and poorly understood.3
Heart fat loss
With disease, EAT promotes unwanted inflammation that induces tissue scarring and alters the activity of hormones that regulate basic body functions like how the heart beats and pumps blood.3 Additionally, epicardial adipose tissue is thought to induce various diseased states like atrial fibrillation and coronary artery disease by promoting structural changes in the heart.3 Accordingly, cardiometabolic disease treatments that induce heart fat loss could be beneficial.
How do I know if I have a dangerous amount of EAT?
Thankfully, there is no shortage of medical tests when it comes to determining the status of your EAT. Imaging tests like 2D echocardiography that show how blood flows in the heart can measure the thickness of epicardial adipose tissue.1 In addition, the more common computed tomography (CT) and magnetic resonance imaging (MRI) scans compute the volume and thickness of this tissue.1 Furthermore, there are functional tests that gauge the level of inflammation, such as the positron emission tomography (PET) scan.1
What can I do about EAT?
Despite being a risk factor for heart conditions, there are lifestyle modifications that can reduce the risks that epicardial adipose tissue poses to health. EAT can be managed with proper diet and exercise, and if needed, medications are necessary interventions.3
Medications for EAT
Drugs that are used to treat type 2 diabetes and high cholesterol have beneficial effects on the cardiometabolic concerns of EAT. This is because the drugs have pleiotropic effects, meaning other effects in addition to the main ones they were designed to have.3
Myasoedova and colleagues.3 comprehensively searched published studies to sum up the pleiotropic effects of cardiometabolic drugs on EAT reduction. They studied three types of drugs known to reduce the risk of cardiometabolic diseases:
- blood sugar increasing Glucagon peptide-1 agonists (GLP-1 RAs),
- blood sugar lowering sodium-glucose co-transporter-2 inhibitors (SGLT2-is),
- and cholesterol-lowering statins.3
The study researchers found that the GLP-1 RAs had the most profound effect on EAT reduction, followed by the SGLT2-is and statins.3 The best responses were evident after six months of use, which is also when the effects of GLP-1 RAs and SGLT2-is on EAT reduction were similar.3 Interestingly, the beneficial effects of these drugs were heightened in patients with a higher body mass index (BMI) and younger age.3
Prospects for the future
EAT is a modifiable risk factor for cardiometabolic diseases. A healthy lifestyle and, if necessary, medications can promote heart fat loss required for achieving the balance between protective and risk factors. Future studies exploring healthy EAT thickness and the biological phenomena behind abnormal EAT activities will enrich our understanding and could prevent serious health outcomes.3
- Iacobellis G. Epicardial adipose tissue in contemporary cardiology. Nat Rev Cardiol. 2022;19(9):593-606. doi:10.1038/s41569-022-00679-9
- Çinier G, Nalbantgil S. Epicardial fat: More than an adipose tissue. Turk Kardiyol Dern Ars. Sep 2021;49(6):427-429. https://jag.journalagent.com/tkd/pdfs/TKDA_49_6_427_429.pdf
- Myasoedova VA, Parisi V, Moschetta D, et al. Efficacy of cardiometabolic drugs in reduction of epicardial adipose tissue: A systematic review and meta-analysis. Cardiovascular Diabetology. 2023/01/31 2023;22(1):23. https://doi.org/10.1186/s12933-023-01738-2