Cardiac MRI imaging isn’t something that usually happens in a routine clinical environment. It requires specialist training to capture and interpret the imaging, and as such, is not currently available everywhere that might need it.
As technology improves though, cardiac MRI has more possible applications and benefits to recommend it. This means that we expect to see more trained technologists and availability in the future.
Here, we’re looking at what is next for cardiac MRI imaging – how has it developed recently and what might we expect to see?
Training more technologists
We already touched on the shortage of qualified cardiac MRI technologists, so let’s look at that first. What is being done to ensure more are trained to perform cardiac MRI?
Specialist training is required to undertake Cardiac MRI which in many cases, means that it is not as widely available as it may be needed. Ensuring that there are enough qualified staff to perform the imaging tasks is an issue for clinics to deal with.
Notably, there are multiple fellowships available, between one month and a year or more. The Society for Cardiovascular Magnetic Resonance Imaging lists many of these on their website. Companies that manufacture the MRI equipment, such as Siemens, also offer training in cardiac MRI.
Why should potential fellows take note? There is a definite trend for noninvasive modalities and safer imaging techniques. Cardiac MRI fits this trend by reducing radiation exposure. It is also a more cost-effective option than others (such as CT), which increasingly makes it a favorable modality.
MRI effective in perfusion testing
Where patients have coronary artery disease or chest pain that is presumed to be stable, their treatment regime depends upon how constricted their coronary arteries are. Traditionally, this means undergoing an invasive cardiac catheterization procedure and potentially, perfusion testing using the nuclear stress test.
Recent studies have found that cardiac MRI is as safe to use for informing treatment decision-making as the more invasive techniques. MRI has the advantage of not using ionizing radiation. The testing can be performed in just 40 minutes using MRI, another advantage over nuclear stress testing.
The study concludes:
“This means that with a fast and non-invasive MRI examination as the first test, both diagnostic and therapeutic cardiac catheterizations can be reduced. Importantly, the two groups (that were studied)did not differ in terms of continuing symptoms, the development of new symptoms, complications, or deaths.”
These results are backed up by a recently published Duke University Medical Center study. The study concludes that MRI not only diagnoses disease, but can also predict which cases are potentially fatal.
Importantly, it’s all adding to the data to show that cardiac MRI is an effective alternative. Robert Judd, Ph.D., co-director of the Duke Cardiovascular Magnetic Resonance Center points out that “We’ve known for some time that CMR is effective at diagnosing coronary artery disease, but it’s still not commonly used and represents less than one percent of stress tests used in this country.” He continues, “One of the impediments to broader use has been a lack of data on its predictive value — something competing technologies have.”
As Vincent L. Sorrell M.D. and Gurpreet Barweja M.D. posit in an article for Cardiovascular Reviews and Reports, we can consider the implications of non-invasive, cardiac MRI for the patient who otherwise has no symptoms of coronary artery disease but is concerned about a family history factor. Where previously (if testing were normal) they may have been advised to return to a physician if they had symptoms, now an MRI is a safe way to get a more comprehensive view of their heart. It can change how otherwise healthy patients are risk-stratified.
These recent studies go some way toward rectifying the lack of data. Crucially, these could see more widespread adoption of cardiac MRI.
Advances in AI (Artificial Intelligence) for MRI
Technology is always one of the main drivers of advancement in the cardiac MRI field. You can perform cardiac MRI on any scanner, however, you do need the right coil and software options. There is even third-party post-processing software that allows images to be sent and analyzed.
Recent technology advances are seeing Artificial Intelligence used to help with pain points related to cardiac MRI. For example, a common complaint is that the process takes a long time and as a result, the exams can be expensive. This is another reason that adoption has not been so widespread.
Where does AI come in? By automating parts of the exam to help reduce that scan time. For example, startup HeartVista showed its technology at the 2018 Radiological Society of North America annual meeting. Their AI-based solution can potentially reduce a 90-minute ischemia exam down to just 15 minutes. One of the benefits of this technology for clinics is that this solution has been made to integrate with existing MRI cameras to guide imaging – no need for expensive new equipment.
MRI for Peripheral Artery Disease (PAD)
On a related note, there is evidence to show that MRI is a useful modality for identifying the toughest lesions in cases of Peripheral Artery Disease (PAD). Where arteries carrying blood to the limbs become blocked, undergoing an endovascular treatment – where a guidewire is used to place a stent – is much less invasive than traditional bypass surgery.
The challenge has been that where a lesion is too difficult to penetrate with the guidewire, the procedure will fail. Until now, there has been no effective way to diagnose which arteries will be too difficult to penetrate, so the patient undergoes the failed procedure and effective treatment is delayed.
Sunnybrook vascular surgeon, Dr. Trisha Roy has developed an MRI technique that will identify early which lesions are too difficult to cross. In this way, MRI can identify patients who are suitable for an endovascular procedure, versus those who aren’t.
Cardiac MRI after Myocardial Infarction
In evidence to show that cardiac MRI is being utilized more often post-myocardial infarction, recommendations have been made for how it can be used in clinical research. The Journal of the American College of Cardiology published a consensus paper from a scientific panel recently.
“Currently, many clinical trials use magnetic resonance imaging to assess a principal outcome, but it is very difficult to compare these studies because they use widely different protocols,” BorjaIbañez, M.D., Ph.D., said in a statement. “Myocardial infarction affects millions of people in the world every year, and this is therefore a highly active field of research. Because of this, the implications of the new consensus document are enormous.”
All in all, a lot is happening in the world of cardiac MRI. While it hasn’t been as widespread as other modalities, it is growing in popularity as a method for reducing radiation exposure, and as common limitations are eased through technological development.
Mobile cardiac MRI is another area that is growing, allowing regions that don’t offer cardiac MRI to access it, or hospitals that are considering offering the service to try it. If you are interested in giving it a try, talk to us at DMS Health today.