A new MRI technique predicts the risk of heart disease based on the fat content in the heart.

Researchers led by Frederick H. Epstein, Ph.D., from the Department of Biomedical Engineering at the University of Virginia, are attempting to utilize magnetic resonance imaging (MRI) to assess the composition of the fat tissue surrounding the heart. Analyzing this tissue will help doctors identify patients at the highest risk of developing potentially fatal heart conditions such as coronary artery disease, atrial fibrillation (irregular heartbeat), and heart failure, as well as predict how well these patients may respond to treatment.

Early trials of the technique have shown promising signs that this approach could become a powerful tool for improving patient care.

“Using the new MRI technique, we can finally learn about the composition of the fat that accumulates around the heart. This is crucial because depending on its composition, fat surrounding the heart can release harmful substances directly into the heart muscle, leading to serious heart issues,” says researcher Amit R. Patel, a cardiologist and imaging expert at UVA Health and the University of Virginia School of Medicine.

In the course of our ongoing research, scientists have demonstrated that unhealthy fat surrounding the heart can be transformed into a healthier type of fat through dietary changes and exercise or through medication. This can reduce the complications associated with heart disease.

Our hearts are naturally encased in a layer of fat known as "epicardial adipose tissue." In healthy individuals, this fat is protective and vital for heart function. However, in some people, particularly those suffering from obesity and having risk factors for heart disease such as diabetes, high blood pressure, smoking, and poor diet, this fat can accumulate excessively, become inflamed, and undergo harmful changes in its composition.

The UVA researchers are using magnetic resonance imaging to evaluate the quantity and composition of fat. This imaging technology essentially allows them to look inside the body without the need for surgical intervention. By analyzing the content of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids in the epicardial fat tissue—fats that are typically present in our diet—doctors will be able to identify patients who may develop heart problems even before symptoms appear. Detecting and addressing this issue could slow the progression of cardiovascular diseases, which are the leading cause of death both in the U.S. and worldwide.

In creating this new tool, researchers at UVA faced several significant challenges. For example, the heart and nearby lungs are constantly in motion, which poses a huge obstacle to obtaining clear images of the fat tissue. However, by developing innovative imaging approaches, the scientists are now able to capture the images they need in a single breath-hold.

The ability to perform such measurements in epicardial fat tissue required the use of advanced computational methods to isolate the unique structure of saturated fatty acids from the overall noisy signal.

The UVA team has already tested its technology both in the lab and on a limited number of patients. They found that the fat around the hearts of patients suffering from obesity and who have had a heart attack consists of an excessive amount of saturated fatty acids. “This indicates that the new MRI technique may become a valuable clinical tool for identifying at-risk patients and predicting their outcomes,” Patel says. “Being able to see the composition of fat surrounding the heart will enhance our understanding of heart diseases and may lead to the development of new treatment strategies in the future.”