Cardiac Magnetic Resonance Imaging (MRI)
Heart Center physicians were the first in the world to report the successful use of magnetic resonance imaging (MRI) to diagnose significant blockages to blood vessels around the heart. Their research has found that MRI studies are highly predictive of future heart attacks. Heart Center researchers are evaluating its use with treadmill stress tests, learning more about the aging process of major blood vessels.
The results of research by a team led by W. Gregory Hundley, M.D. associate professor of cardiology and radiology at Wake Forest University School of Medicine received international attention when released last fall in Circulation. By speeding up the MRI scanner and creating new software, Medical Center researchers have made it possible for physicians to see heart movement within seconds after it happens—compared to an average of five minutes to see images previously.
The discovery was an important step in making MRI a screening and diagnostic tool for heart disease. Currently, ultrasound is the most common non-invasive test for detecting heart disease. However, approximately 10-20 percent of people cannot have the ultrasound test because they are obese or have health conditions like emphysema that interfere with getting a clear image of the heart.
“MRI is a non-invasive alternative for people who cannot have an ultrasound, said Hundley. These are often our sickest patients.” Hundley’s research team found that the MRI test is just as accurate as ultrasound at diagnosing blocked arteries.
The software, developed by Craig A. Hamilton, Ph.D., associate professor of radiology at Wake Forest, allows researchers to see the heart’s action almost immediately. “This faster imaging and visualization is what makes it possible to do a stress test with MRI,” said Hundley.
As with ultrasound, the goal of a stress test is to view the heart during vigorous pumping. However, some patients are not able to exert themselves at the rate necessary to perform the test. During the MRI test, patients are given drugs to speed up their hearts so they beat at close to capacity. The scan is complete in about 35 minutes.
Because MRI can evaluate many parts of the body, the test could be useful for patients with multiple symptoms. For example, a patient could be tested for blood vessel disease in the coronary arteries and in the legs at one time.
The Medical Center is one of only 15 sites in the nation approved by the Food and Drug Administration to perform the test.
The Heart Center was one of the first centers in the world to use new flat-plane digital cardiac imaging. In interventional procedures such as angioplasty, superior imaging allows for more exact stent placement, with a radiation dose that is as much as 50 percent lower than conventional imaging technologies.
Learn more about the Cardiac MRI procedure.