Philips – In your words, could you briefly describe what iFR technology is?
Dr. Davies – In a nutshell, iFR is a measurement tool that is used to assess the severity of coronary artery stenosis through the use of invasive coronary pressure wires which are placed in coronary arteries. Compared to fractional flow reserve (FFR), iFR offers a faster adjunctive diagnostic solution, with significantly reduced patient discomfort, while helping to deliver consistent patient outcomes.
Philips - Can you briefly describe the journey of the iFR technology – from its introduction to physicians in 2010 to its adoption today.
Dr. Davies – As cardiologists, we are always looking for the best ways to assess our patients. Although FFR was considered most effective at the time, we wanted to look at a different way to approach coronary lesions. We began work on the iFR technology in 2010, and first presented and published data in 2011. This was just a small study that compared iFR against FFR which showed the two to be comparable.
Further validation work was done by our groups and others around the world to compare iFR against other reference standards, leading to sufficient confidence in technologies to perform a large randomized clinical trial. This has resulted in early adoption in Japan and Europe. The technology also moved fast to get CE mark and FDA clearance in 2014, which led to wide adoption in the U.S.
Philips - What are the benefits of an iFR-guided strategy? How does it compare to an FFR-guided strategy?
Dr. Davies - The results of our study, DEFINE FLAIR, showed that in 2,500 patients, using iFR and FFR, revascularization had similar outcomes after one year in terms of overall treatment and deferral, but iFR can be performed quicker and with less discomfort for patients. This is because the overall procedural time is reduced and there are no requirements for hyperemic agents.
Philips - What helped this technology develop so quickly?
Dr. Davies - Physicians across the world were already familiar with the FFR technique, making the switch quite easy from a technical perspective. This is because the technique and wire remain unchanged and all that is required is a software upgrade for the console.
Philips - What was the overall reaction to iFR when it was first released in 2011? Has it changed since then?
Dr. Davies - It was very well received. Then - as always happens - you have people with competing interests and groups scrutinizing it, which is good for the evolution and development of any new technology. As soon as iFR was commercialized, people started testing it for themselves in their own labs, and from there the confidence started to grow.
It’s the same as if it there was a new drug or treatment tool - you need to have good validation in large randomized clinical trials before you can get guideline adoption, as well as the confidence of physicians.
This is what has happened with our DEFINE FLAIR and iFR Swedeheart studies, which were supplemented by positive responses from journal publications, resulting in increased adoption and changes the Appropriate Use Guidelines. Now that iFR is available as well as FFR, physicians have another choice at their disposal.
Philips - How have the DEFINE FLAIR and iFR Swedeheart studies results impacted the general opinion of iFR?
Dr. Davies - Most physicians are very data-driven and want to see the facts before they make clinical decisions on what techniques and equipment they should use. The DEFINE FLAIR and iFR Swedeheart studies were the biggest studies that tested iFR use across 4,500 patients – a large number especially when compared to the last FFR study that took place more than 20 years ago, that included just 90 patients.
The data from these studies dwarfed the results of other similar studies, which gave clinicians a great deal of confidence in using iFR and FFR-based techniques.
Philips - What do you think are the largest barriers to introducing new technology?
Dr. Davies - Reimbursement. Healthcare systems around the world are struggling and it’s very hard to get reimbursement for new technology. Medical facilities everywhere are trying to reform and grow, but for that they need funds. Currently, it’s quite difficult to introduce new technology or new diagnostic tools because of the constant pressure to keep expenditures at a minimum.
Even if the technology can save money in the long run, it really depends on where you are in the world. For instance, the US looks at things more objectively and are more likely to invest, whereas in the UK they simply don’t have the funds to do so.
However, the field of cardiology has a rich pipeline of new technology still to come. Like all medical professionals, we are always keen to learn new techniques and modernize their practice. By working with engineers and companies in the development of these new tools, we can always make sure that we are giving our patients access to the very best care.
Philips - In your opinion, what is the most important thing to consider when introducing new technology that benefits physicians and patients?
Dr. Davies - You have to have data that proves its worth. There are countless examples of technology that was adopted too early before quickly showing its weaknesses. Although their problems are sometimes addressed and dealt with, data will always be the most important thing. By having well-conducted trials you can not only prove the worth of a technology, but you can be confident in it as a long-term solution.
Philips - Where do you see the next step for iFR to be?
Dr. Davies - As we make things easier and simpler to use, we will be able to better integrate systems into each other and create a more personalized service for individual patients. For instance, instead of implanting stents into all suspect areas, we will be focusing our stenting into areas where they are more likely to have a benefit, and leaving those where the benefits are negligible.
I believe iFR will be adopted by guidelines and committees all around the world. I think in a few years, we will have full economic costing models, which will address the full economic benefits of an iFR-based approach, therefore making it more attractive to all stakeholders.