Biggest Barriers to Cardiac CT? Old Myths, Fair Payment, and De-adoption

The main barriers currently impeding increased adoption of cardiac CT include the persistence of old myths, a shortage of trained imagers, and a lack of guidelines, according to Ron Blankstein, MD (Brigham and Women's Hospital, Boston, MA), who spoke on the topic at the Society of Cardiovascular Computed Tomography (SCCT) virtual meeting.

However, this imaging modality has been around long enough that proponents also need to fight the phenomenon of de-adoption, according to Blankstein, the SCCT’s current president.

“We've had so many advances in cardiac CT,” he told TCTMD after his talk. “We are arguably the test that has the most evidence for improving patient outcomes, so the natural question that is often asked is: well, why is this test not being used more? It's got robust evidence base, it can improve patient outcomes, yet when you look particularly in the US, the utilization of cardiac CT is far lower than many would predict or many would have anticipated.”

Old Myths, Inadequate Workforce

When cardiac CT was emerging as a new technology, there were many “appropriate criticisms,” Blankstein acknowledged. “But as the evidence base has evolved, a lot of these criticisms are now ones that we would say are myths and don't reflect the reality on the ground.”

For example, the notion that identification of plaque is not important because “most patients have some” is no longer relevant given findings from SCOT-HEART showing that plaque detection can lead to better medical therapy and improved outcomes, he explained. Additionally, while CT cannot detect ischemia and many have been concerned about sending patients for further unnecessary testing, several studies have shown that only 10-20% of patients have identifiable lesions that require this, Blankstein said. Moreover, as the ISCHEMIA trial made clear, presence of ischemia is losing ground as a predictor of which patients will benefit from more aggressive care.

Also, cost-effectiveness analyses from both PROMISE and SCOT-HEART have shown that CT does not lead to higher downstream costs, and the once-high radiation dose associated with CT has dropped by about 70% over the past 15 years, he highlighted. Lastly, for those who may argue that CT does not improve patient outcomes, Blankstein said, “we know that CT is associated with approximately a 30% reduction in the rate of subsequent myocardial infarctions,” when used as part of the diagnostic workup.

Another barrier to increased use of cardiac CT is that not enough physicians are trained to read these images, especially in the United States. “If we look at how many physicians are certified at reading cardiac CT compared to another frequently used test, which is nuclear cardiology, we see a dramatic difference between these two,” he noted.

Blankstein told TCTMD that the reason for the current shortage of imagers is likely multifactorial. “If you want to read cardiac CT, like any other imaging modality, you have to invest extra time in doing so. This is not something that is part of a traditional radiology residency or cardiology fellowship,” he said, adding that if hospitals aren’t being adequately reimbursed for these tests, they’re less likely to invest in training and hiring people to read them. “It's circular logic in a way.”

Economics, Guidelines, and Education

The third major obstacle standing in the way of greater adoption of cardiac CT is economics. Last year, the Centers for Medicare & Medicaid Services announced that it was cutting reimbursement for the three main billing codes by nearly 30% as part of the Hospital Outpatient Prospective Payment System (OPPS.

“Payment today is lower than the actual cost of providing the test,” Blankstein said. “So if you're a hospital, you may not be trying to make money off of doing test, but you certainly don't want to lose money. Whenever you have a test where the payment that you get for it is lower than the cost of providing, that's certainly a barrier to adoption.”

An informal poll of colleagues around the world points to a wide variety of reimbursement models for chest CT and coronary CT—the latter of which requires more of an investment. While these two are reimbursed at the same rate in the United States, Israel reimburses four times as much for coronary CT angiography, the United Kingdom triples payment, and Brazil reimburses at least double. “I'm not really sure what the right answer is, but I can assure you that it's not 1:1 ratio because coronary CT requires a lot more resources than a chest CT,” Blankstein said.

He pointed to guidelines as the fourth main barrier to cardiac CT adoption, especially the fact that the US chest-pain guidelines are still in progress. However, Blankstein said, “I think it's important to acknowledge that their impact on test utilization is often overstated. At the end of the day, guidelines are used to provide some guidance, but clinicians use many other factors in deciding what other test to provide, ranging from clinical availability and expertise to also their prior experience and their prior training. . . . Guidelines are I think an important factor, but there are many other factors that determine test utilization.”

Lastly, he said there needs to be greater emphasis on educating the “end users” of cardiac CT, namely referring physicians, about when this test is useful—or not—and how to use the results in patient management. “When is medical management alone sufficient? When is stress testing needed? And when do patients really need to go to invasive angiography? This is really important, and I urge everyone watching this who may be the local CT champion in their center to be the person who educates everyone in their community how to use the results of cardiac CT,” Blankstein said.

Preventing De-adoption, Consultancy Service

Taking down the barriers to adoption is not the only task the cardiac CT community needs to focus on, Blankstein stressed. “One of the really important forces that we all have to realize is a de-adoption force, and that is when cardiac CT studies are not useful or inaccurate.”

The more that happens, the more referring physicians might think that CT isn’t helpful and that perhaps they should be ordering another test. In order to prevent this, he said, “the first thing we need to do is to make sure that we only do tests on patients when we know we can get good image quality. Coronary CTA is absolutely a test that's dependent on the technique and on image quality, so if you have a patient with small stents, someone who cannot hold their breath, or someone who's tachycardic that you cannot control, that might not be a good patient for cardiac CT.”

Commenting on the presentation for TCTMD, Maros Ferencik, MD, PhD (Oregon Health & Science University, Portland), said he especially agreed with Blankstein regarding the need for increased education beyond “our core group” of imagers. “It used to be very easy,” he said. If you were an emergency department physician the evidence at your disposal was based on whatever test your institution routinely performed. “When I trained at Mass General, it was nuclear stress test,” Ferencik recalled. “And everybody who came went through the rule-out myocardial infarction protocol [and] got a nuclear stress test. There was very little consideration of: who is this patient, is this the right patient for this test? Now in 2020, our armamentarium of tests has changed.”

This increased availability of options has been a boon for the field of imaging, but can also be very confusing for those not trained in the intricacies of each modality, Ferencik said. “When [societies like the SCCT] are thinking about how we create our educational programs, conferences, and online education, we need to take this into account and reach out to those people so they know what we do, they know why and for whom the CT is the right test.”

He added that he would also like to see a greater emphasis placed on multimodality imaging. “The challenge for the imaging physicians or imaging specialists is that we traditionally have worked, many of us, in silos,” Ferencik said. “As we expand our armamentarium of imaging tests, it becomes more important to not only know what your particular test does in your subspecialty, but what other areas of imaging can provide and what are the advantages and disadvantages of each of the methods for particular indications.”

In the near future, it would be good to see imaging specialists serve more of a consultancy role, he suggested, where “people ask us how to answer their clinical question [and we] will provide advice on how to image that particular question to answer it.” Machine learning may come to play a larger role in the process, and that is not something to be feared, Ferencik added. While computers may become better than physicians at certain tasks, “time hopefully will be freed up to provide advice, help, and consultation to our nonimaging colleagues to tell them if you have ‘problem X,’ CT will answer this question and may be the right test or echocardiography will answer another question that clinically is medically relevant.”