An Interview with Antreas Hindoyan, MD Dr. Hindoyan, interventional cardiologist at Keck Hospital of USC, discusses the future of coronary physiology and how the CathWorks FFRangio™ System can provide value for PCI decision-making.
How have you integrated wire-based FFR into clinical practice at Keck Hospital of USC? Why is it important for your practice?
I’ve been using FFR since I was a cardiology fellow, and it has become an integral part of our standard PCI procedure workflow at Keck USC. FFR is now a part of the vernacular among the staff. Whenever we have a questionable lesion, it’s not only the doctor suggesting a physiology assessment—the techs and staff are also vocal about using FFR.
The whole goal of treatment is to make the patient feel better and improve outcomes. For patients with stable CAD and an intermediate lesion, it can be unclear which treatment is best for them. That is where an objective measurement will be most useful. If you have a lesion that is not hemodynamically significant, the data shows that a stent will not provide any extra benefit compared to medical therapy. So FFR really standardized our process of deciding which CAD patients should get a stent and which should not.
Are you seeing more hospitals adopting FFR over time?
Yes. Over the last 10 years FFR utilization has increased steadily, and it’s starting to become standard of care in most hospitals. FFR is very easy to conceptualize and provides a clear benefit, and that’s part of the reason why more physicians are adopting it.
I think we’ll see more growth and adoption going forward. It will continue to be important for physicians to have clear documentation of hemodynamic significance prior to stenting, especially for patients with intermediate lesions. Even if the patient arrives at the Cath lab with a stress test or a nuclear test, there is no substitute for a significant FFR value to determine if the patient needs a stent.
Data continues to support broader use of FFR to guide PCI decision-making, but it’s still underutilized compared to clinical guideline recommendations. What needs to happen to make FFR standard of care for more patients?
Procedure time is a big factor. In the Cath lab, the most important commodity is time. The longer you stay in the Cath lab, the greater the risk of complications, patient discomfort, and other issues. You want to be as efficient as possible.
For pressure wire FFR, you need to consider how Adenosine might affect the patient. Hyperemia causes drops in blood pressure and patients feel flushed, which they don’t like. And if you have a patient with a tenuous blood pressure, you might have some issues.
There’s also a risk of complications, especially with oldergeneration pressure wires that are more difficult to handle compared to standard workhorse wires. It would be horrible to cause a dissection in the vessel during a simple diagnostic test. And if a patient has thrombocytopenia, high INR, or cirrhosis with a low platelet count, you want to avoid heparin and placing a wire unless you really need to.
I think all these factors give pause to the interventionalist, which explains the underutilization we’re seeing. Any new FFR technology that addresses some or all these limitations would be very welcomed in the Cath lab.
You’ve been using the wire-free and drug-free CathWorks FFRangio™ System for about a year now. What was your initial experience like?
As an interventionist, you are generally skeptical of new technology, so we wanted to validate the technology ourselves. Early on, we had a patient with a mild/intermediate lesion that I would have guessed did not need a stent. We decided to run an FFRangio analysis and the results showed FFR was significant at 0.72, which was surprising. So, we ran a wire-based FFR just to be sure and got a very similar result. Clearly, there was correlation between the two technologies, and they both told me something different than what I predicted based on the angiogram. We ended up stenting and the patient did great with a lot of symptom improvement. That was a galvanizing experience for us and the moment we knew the technology worked. And we had several similar cases after that, which gave us a lot of confidence. Once we adopted the technology, we started using it in patients we would not normally use wire-based FFR in. Since it doesn’t require heparin or Adenosine, we can actually apply it to more patients.
What do you think are the main benefits of FFRangio compared to traditional wire-based FFR?
FFRangio has added both benefit and safety to the Cath lab. Getting rid of Adenosine is important, especially for patients with a tenuous blood pressure. But we’ve seen a greater benefit in getting rid of heparin. For some patients, we’re hesitant to use a pressure wire because of the risk of complications and bleeding from anticoagulation. Now we can evaluate these patients with FFRangio and still get an accurate FFR measurement. If the patient has a normal FFR, it’s nice that you can send the patient home with just a diagnostic angiogram, and you would have avoided heparin and Adenosine.
The ability to get results quickly in multiple vessels is another advantage of FFRangio. Sometimes you have multiple lesions, and you need a treatment strategy for each one. With the wire, you would have to do multiple measurements, and you need to be sure the Adenosine has completely left the system before the second injection. With FFRangio, you don’t have to worry about that because the analysis is based on angiogram images.
What has the process been like to integrate FFRangio into practice at Keck USC? Any advice for other physicians considering the technology?
In our lab, our CV techs and nurses run the FFRangio analysis. They get the analysis started while I take some additional images. I assist with selecting angiograms and identifying vessels/lesions, but our staff usually drives the process. Our CathWorks rep was great in helping us get comfortable with the technology and get past the initial learning curve. Speed, accuracy, and ease of use are the most important factors. I’ve now seen a couple product iterations and with every update, it’s become more efficient, faster, and more user friendly. I think FFRangio has been easy to use for our team.
I am very happy I had the opportunity to be one of the early adopters of FFRangio. I’m a firm believer in the technology and think of it as my first-line tool for physiology guidance. My advice to other physicians is to try it. Once you have the proper training, it makes your Cath lab more efficient and safer and takes the guesswork out of some complex patients where the wire may not be the optimal choice.
Now that non-invasive technologies like FFRangio are available, what do you think is the future of physiologybased PCI guidance?
I think use of physiology guidance will continue to increase over time. The patient benefit is clear, and you always want an objective justification for the stenting decision. One area I think we’ll see some growth is evaluating FFR after PCI. There’s value there, but the concept has not yet caught on because interventionalists are hesitant to place another wire and risk a potential complication unless they have to. With a non-invasive technology, you might be more inclined to check FFR after stenting and provide additional treatment if the resulting FFR value is still low.*
Another interesting application: in some hospitals, you may also start to see non-interventional cardiologists adding an FFRangio analysis to their diagnostic angiograms. Since it doesn’t require an additional intervention, it creates an opportunity to assess FFR for cardiologists who wouldn’t normally do a wire-based procedure. I can absolutely see quick, non-invasive FFR technologies like FFRangio replacing wire-based methods and becoming the first option for physiology guidance. Ultimately, by expanding the patients who can get FFR, it should improve outcomes and satisfaction for more patients.
*Diagnostic performance of FFRangio compared to FFR wires has not been established for lesions immediately after PCI.