Better provision of hands-on education and case-based learning models are among the actions that will help to drive greater adoption of intravascular imaging technologies to support coronary interventions.
This is according to a panel of experts who have reviewed current barriers to more widespread usage of imaging technologies—including intravascular ultrasound (IVUS) and optical coherence tomography (OCT)—which remains low despite latest clinical practice guidelines favouring their use in specific clinical and anatomical scenarios.
Last year, updated European Society of Cardiology (ESC) chronic coronary syndrome guidelines brought in a class 1, level of evidence A recommendation for imaging in complex scenarios including left main disease, bifurcations, or long lesions, with subsequent guidelines from the American College of Cardiology (ACC) and American Heart Association (AHA) also carrying a similar weight of recommendation.
Advocates of intracoronary imaging were optimistic that these guideline changes would bring about a shift in practice to see more imaging used for coronary interventions, but a wide-ranging white paper published in the Journal of the Society for Cardiovascular Angiography & Interventions (JSCAI) by authors Javier Escaned (Hospital Clínico San Carlos, Madrid, Spain) et al acknowledges that adoption has remained low in many regions with wide disparities in usage opening up across the world.
“The question is: how is it possible that something that contributes to saving lives and has a 1A recommendation in clinical practice guidelines does not get accepted?” Escaned comments to Cardiovascular News, setting out the rationale for the discussion paper. “I was discussing this with colleagues, and we thought we didn’t need one more paper highlighting the importance of this for clinical benefit or giving a clinical consensus statement, we need to explore what is going on here.”
As well as looking at current rates of usage of intracoronary imaging and existing barriers to adoption, Escaned and colleagues set out a series of concrete actions that they believe will cement the use of imaging into clinical practice—with an aim to encourage acceptability, acceptance and adoption of imaging amongst interventionalists. Whilst recommendations cover a broad set of issues including referral, reimbursement, data collection and reporting, and engagement with cath lab teams, there is strong emphasis on education and the way that interventionalists are trained in when and how to use these technologies.
“In some regions reimbursement has been suggested as a reason. It is important to advocate for better financial incentives. After all, imaging permits better optimisation and more accurate evaluation of the stent results with fewer stent failures and event rates,” Mirvat Alasnag (King Fahd Armed Forces Hospital, Jeddah, Saudi Arabia) tells Cardiovascular News.
“Another important factor, however, is training. It is important to note that up until five years ago, the majority of operators were trained in the non-IVUS/OCT era. They’ve grown comfortable sizing stents and identifying landing zones without imaging. As such, they didn’t feel the necessity of intravascular imaging despite the plethora of evidence.
“In order to get them to that level of comfort in image acquisition and interpretation, robust training programmes and technical support were necessary in coordination with industry.”
Though the use of intravascular imaging is seen as a relatively new innovation in the field of coronary interventions, Escaned et al’s paper identifies that these technologies have been in circulation for several decades, noting that in Japan, for example, where as many as 84.4% of percutaneous coronary intervention (PCI) procedures involve the use of IVUS or OCT in some form, the use of intracoronary imaging has been relatively well established since the mid-1990s.
However, the East Asian country stands as an outlier globally, as nearly all other nations lag significantly behind in their uptake of intracoronary imaging—a fact that is attributed to a multitude of issues including availability of technologies, lack of training and inconsistencies in reimbursement, to name just a few.
In the UK—which is among the more rapid adopters of intracoronary imaging according to figures quoted in the JSCAI paper—imaging is used in around 25% of cases. “In recent years there has been considerable progress in the adoption of intracoronary imaging within the UK—the majority of left main procedures are now done with intravascular ultrasound. This is at least in part to do with continued emphasis by the British Cardiovascular Intervention Society (BCIS) on quality improvement and optimising patient outcomes,” Adrian Banning (Oxford Heart Centre, John Radcliffe Hospital, Oxford, UK), a co-author of the white paper, tells Cardiovascular News, reflecting on how practice has begun to shift in the UK. “However, it is clear that use of imaging in the UK is still patchy and there remain areas where use of imaging is infrequent, even in complex procedures.”
The USA is another more rapid adopter of intracoronary imaging techniques, with the JSCAI paper quoting usage at around 15.4%, but it is noted that there is wide variability within the country, “mainly driven by hospital and physician rather than PCI complexity or patient-level characteristics”. This is underscored by data published in The American Journal of Cardiology in July showing that despite an increase in intravascular imaging usage over time, prevalence of imaging is far lower in the country’s southern states (7.6%) than in western states (12.6%), for example—hinting at a disparity in care opening up at more local level.
“Intravascular imaging use for guidance of PCI procedures remains low in the USA, despite indisputable evidence that such routine use substantially reduces mortality, myocardial infarction, stent thrombosis, and repeat intervention,” Gregg W Stone (Icahn School of Medicine at Mount Sinai, New York, USA), who has contributed to several key randomised trials in this domain, tells Cardiovascular News, discussing current usage amongst US interventionalists.
According to Stone, there are a multitude of reasons why adoption continues at a slow rate in the USA, citing factors including poor training, as well as operator perception of the technologies. “I believe the major factors are lack of training and knowledge of how to implement all the information inherent in IVUS and OCT images into actionable practice (most common in older physicians); perception of increased time required; lack of reimbursement; and frankly, hubris—the mistaken belief by selected physicians (again, mostly the older generation) that their patient outcomes are as good with angiography-guided PCI as with intravascular imaging-guided PCI, despite more than 20 randomised trials showing the opposite,” he comments.
Stone says that he remains optimistic that with class I guidelines now in place in both the USA and Europe for the routine use of intravascular imaging guidance for PCI in complex lesions, adoption rates will increase to a more acceptable level. “Such rates are being achieved in certain states such as Michigan and hospital systems such as the Veterans Affairs (VA) where clinical pathways for optimal practice are implemented and metrics are reported,” he says.
If the UK and USA are among the more rapid adopters in the western world, of the major European nations highlighted in the paper, France has the lowest overall use of intracoronary imaging as a percentage of PCI, with an overall rate of 1.7%.
According to Escaned, the reason for such wide disparities among developed nations rests with how the benefits and use of the technologies are communicated to interventionalists.
“Interestingly, I’ve heard some cardiologists argue that the limited use of imaging in their countries proves it isn’t necessary. My question is: what advice would these cardiologists give to a colleague practicing in Japan, where utilisation rates are considerably higher?” Escaned comments to Cardiovascular News, citing this as a form of “cognitive dissonance” in effect, whereby operators who have been educated in an angiography-based culture may have their expectations challenged by the introduction of new technologies.
Escaned believes that “practical” educational models will be key to overcoming this challenge. “The way that you use imaging in clinical practice differs for the different clinical subsets and education has to be focused on what actionable information you obtain from IVUS in each different scenario that you can apply to your intervention, so that is something that is truly important.”
Offering examples of how educational activities could be changed to demystify intracoronary imaging techniques for operators who may have reservations about using them, Escaned says that hands-on or case-based learning models may facilitate uptake more effectively than traditional evidence reviews or technical lectures, whilst activities should promote clinical benefit as well as seeking to improve imaging interpretation skills.
Additionally, Escaned says that users must be shown techniques in a way that can be easily transposed into their own practice and says that educators must avoid portraying intracoronary imaging as something that only the top experts can replicate.
“If you are showing a live case that is guided with intracoronary imaging, and you see that there is a super expert by the table performing IVUS and making the analysis, you are extending the idea that you need such a person to use IVUS in your cath lab,” he comments. “It is completely wrong. The logical idea is that you see that it is used by operators, that it is fully integrated in what they do. It is an example of how you may be sending the wrong message.”
Escaned says that the framing of debate in educational sessions as having individuals speaking for or against the use of the technology may also be counterproductive. “With a 1A recommendation it should be crystal clear that intracoronary imaging in complex PCI saves lives,” he says. “In my opinion, there is no room for giving the microphone to someone who says that this is not really working; once the evidence and expert opinion are so well established, attention should move from debate to promoting adoption.”
Of the potential impact of the white paper, Escaned says he hopes that all stakeholders involved in medical education, including industry, will take into consideration the suggestions put forward to expand the practice of intracoronary imaging.
“Hopefully all colleagues that are involved in medical education and congresses will try to follow these recommendations on how to provide educative models that avoid the problems we have highlighted and align better. Industry also plays a very important role in education. Making sure that the first experience the interventional cardiologists have with intracoronary imaging is successful, and they realise that they are getting actionable information to improve the procedures, these are aspects that are important.”
