In October, a crane carefully lowered Eastern Ontario’s first dedicated magnetic resonance imaging (MRI) scanner into a narrow access way so that it could be rolled through the exterior wall of the building and into position. By early December, the new MRI facility was fully commissioned and open to serve the 1.2 million residents of the Champlain region.
Until now, the University of Ottawa Heart Institute had shared The Ottawa Hospital’s MRI facility. But with so many other specialties—including neurology, orthopedics and oncology—clamouring for time on that machine, the wait lists were long and growing, explained Alexandre Dick, MD, who will co-lead the Heart Institute’s Cardiac MRI program with cardiac radiologist Carole Dennie, MD. “Cardiovascular problems often can’t wait for a long time. They need to be imaged quickly. So we needed our own dedicated cardiovascular scanner.”
Not every patient referred to cardiac imaging requires an MRI scan; in fact, most do not, explained Dr. Dick. For simply imaging blockages in the coronary arteries, computed tomography (CT) remains the test of choice, while nuclear imaging can clearly visualize blood flow to the heart muscle.
“But for measuring heart function, heart size and heart shape, cardiac MRI is the current imaging gold standard,” said Girish Dwivedi, MD, PhD, a cardiologist who will lead the MRI facility’s research program. This means that for patients with diseases like cardiomyopathy or congenital heart malformations, an MRI scan will be invaluable for obtaining a clear diagnosis. MRI can also be used to resolve conflicting or inconclusive results obtained from other imaging tests.
“With CT or nuclear imaging, you can see that there might be something that’s abnormal in the heart, but you won’t know what that is. MRI can tell you if it’s fat, if it’s clot, if it’s muscle, if it’s tumour. It can give a lot more information than other imaging techniques, at a very, very high resolution, without any radiation and often without any contrast agents,” said Dr. Dick.
The clarity and reproducibility provided by MRI also makes it the gold standard for cardiac clinical trials, explained Dr. Dwivedi. “Because cardiac MRI is so accurate, we can reduce the number of patients needed to obtain a meaningful conclusion. So it reduces research costs in the long run because we can both recruit fewer participants and get more accurate data.”
Because an MRI scan uses significant imaging resources—the team expects to be able to perform around 10 to 15 scans a day—research staff want to make the most of each scan. “Suitable patients undergoing cardiac MRI will be invited to take part in ongoing research studies, which in some cases may mean just enrolling them in a registry,” said Dr. Dwivedi. Such a registry will allow the group to go back and examine correlations between patient outcomes and cardiac abnormalities seen on MRI.
Cardiac MRI remains an expensive test but can be cost-effective when used to minimize the overall amount of testing a patient undergoes. “We don’t want to perform a test, find it inconclusive and then have to order another test. This is inconvenient to patients, increases the cost of health care and may expose patients to additional risk,” said Benjamin Chow, MD, Director of Cardiac Imaging.
“We’re extremely excited to have this technology and that our patients will have access to it. Our ultimate goal,” he said, “is to provide the best care, and having access to all the latest equipment allows us to do that.”
[This post is adapted from an article that first appeared in The Beat.]