New MRI Technique Predicts Heart Disease Risk

Everyone is aware of the health concerns of carrying too much fat around the waist and hips, but UVA Health researchers are developing new MRI Technique – a noninvasive method to measure the health risks of invisible fat around the heart.

The researchers, led by Frederick H. Epstein, PhD, from the University of Virginia’s Department of Biomedical Engineering, want to use magnetic resonance imaging (MRI) to determine the composition of adipose tissue (fat) that surrounds the heart. Analyzing this tissue could help doctors identify patients who are at high risk for potentially fatal cardiac problems like coronary artery disease, atrial fibrillation (irregular heartbeat), and heart failure, as well as predict how well those patients will respond to treatments.

“Using this new MRI technique, we now for the very first time have the ability to know the composition of the fat that accumulates around the heart. This is important because depending on its makeup, the fat which surrounds the heart has the potential to release damaging substances directly into the heart muscle, leading to serious heart problems,” said researcher Amit R. Patel, MD, a cardiologist and imaging expert at UVA Health and the University of Virginia School of Medicine.

With our ongoing research, we hope to show that we can convert the unhealthy fat which surrounds the heart to a more healthy type of fat with either diet and exercise or through the use of medications. We believe that by doing so, we will be able to reduce some of the complications associated with heart disease.”

Amit R. Patel, MD, Cardiologist and Imaging Expert, University of Virginia Health System

The heart of the matter

Our hearts are naturally surrounded by a layer of fat known as “epicardial adipose tissue.” In healthy people, this fat is protective and vital for heart function. But in some people, particularly people with obesity and risk factors for heart disease such as diabetes, high blood pressure, smoking and a poor diet, this fat can accumulate excessively, become inflamed and undergo harmful changes in its composition.

UVA researchers would employ MRI to determine the amount and composition of fat. The imaging technology allows them to view into the body without the need for surgery. Doctors may be able to identify individuals who may have cardiac problems before symptoms arise by assessing the quantities of saturated fatty acids, monosaturated fatty acids, and polyunsaturated fatty acids – lipids usually linked with our meals – in the epicardial adipose tissue. Identifying and addressing this problem has the potential to halt the progression of heart disease, which is the leading cause of death in the United States and around the world.

UVA researchers faced significant obstacles when developing the new tool. For example, the heart and adjacent lungs are constantly in motion, making it difficult to get clear images of adipose tissue. However, by developing novel imaging approaches, scientists are now able to obtain the images they require in the space of a single breath hold.

“The ability to make these measurements in epicardial adipose tissue required the use of advanced computational methods that can extract the unique signature of saturated fatty acids from an overall noisy signal. Jack Echols, a biomedical engineering graduate student in my research lab, did outstanding work to develop these methods,” said Epstein, associate vice president for research at UVA. “We’re excited to partner with cardiologists like Dr. Patel to explore clinical applications of this method, and hope that this method ultimately leads to more precise treatments and better outcomes for patients with heart disease.”

The UVA team has already tested their technology in both the lab and in a limited number of human patients. They found that that the fat around the heart in patients who were obese and had suffered heart attacks was comprised of an excessive amount of saturated fatty acids. “That suggests that this new MRI technique could become a useful clinical tool for identifying at-risk patients and predicting their outcomes,” Patel said. “Being able to see the composition of the fat that surrounds the heart will improve our understanding of heart disease and may lead to the development of new treatment strategies in the future.”