Epicardial fat releases inflammatory molecules such as interleukin-6 and tumor necrosis factor alpha directly onto the heart muscle and coronary arteries, promoting cardiovascular disease.

Study: Correlation of Epicardial Fat Thickness With the Severity of Coronary Artery Disease

People with more fat around their heart had much worse heart artery blockages, suggesting that this fat might be harming the heart — even though the study didn't measure the exact inflammatory chemicals.

Study: Relationship between Epicardial and Coronary Adipose Tissue and the Expression of Adiponectin, Leptin, and Interleukin 6 in Patients with Coronary Artery Disease

The study found that the fat surrounding the heart makes more inflammatory chemicals like IL-6 than other fat in the body, especially in people with heart disease. This supports the idea that this heart fat directly harms the heart and arteries by causing inflammation.

Study: CT-Assessment of Epicardial Fat Identifies Increased Inflammation at the Level of the Left Coronary Circulation in Patients with Atrial Fibrillation

This study found that the fat around the heart’s main arteries is more inflamed in people with a common heart rhythm problem, even when their arteries aren’t more blocked. This suggests that this fat is actively producing harmful inflammation that affects the heart.

Study: Correlations between coronary calcium score, FAI index of epicardial fat inflammation and regional distribution of pericoronary inflammation - insights from the IntelFAT study

The study found that areas of the heart with more calcium buildup (a sign of artery disease) also had more inflammation in the surrounding fat, suggesting that this fat is actively contributing to heart disease.