Intravascular Ultrasound (IVUS) Imaging: Benefits & Drawbacks

[Dr. Sabeen Dhand]
Absolutely. It's been a whole difference to me now, the past year, having this new system, and it's just been tremendously helpful having that fellow or doing it yourself, rather than just relying on nothing. You've released an article last year, about the benefit of IVUS. Tell me how you organized the data, and what it really said. Just give us a little summary first, and we'll dive into it.

[Dr. Eric Secemsky]
Yeah so, I think the big question we ran into is-- We've got a lot of great studies that have come out, supporting IVUS, use is up, in particular, in the venous side, use is very high in the venous side, but we've got many specialties performing procedures in different ways, for different indications. So, this is one of those situations where we step back, and we all love randomized trials. I love randomized trials. This is such a mature field. It's a safe device.

Again, as you even speak about in your own experience, once you start using it, you see the benefit of it, was-- How do we harmonize this across specialties, across arterial and venous beds? Harmonize the data, harmonize expert opinion, and create a little bit of a guide for new users to follow, and feel that they are doing things in line with more experienced users. I think that was really the origin of how we put together this consensus document.

[Dr. Sabeen Dhand]
Exactly, how many people did you have? Tell me about your data.

[Dr. Eric Secemsky]
Yeah. Most important thing was, it had to be representative of all specialties practicing in our field and that was the number one key for this. It had to be completely independent of any external industry relationships. How this started was a conversation, honestly, with Phillips in Boston, about how do we create a better template, a better format for incorporating IVUS, and the appropriateness of IVUS in lower extremity interventions.

Myself, Sahil Parikh at Columbia, Ken Rosenfield at Mass General, created a 12-person steering committee. This is all on the JACC Interventions publication that, hopefully, we'll be able to link to the podcast, but we had 12 members who were a mix of vascular surgeons, interventional cardiologists, interventional radiologists, and vascular medicine specialists, from both the US and abroad. We really had a well-rounded group of experts who were really experienced users, but also balanced, in terms of their perspective.

Some people felt like IVUS is important, but not for every case. Some people were more like me, where I felt like IVUS, if I could, I'd use it in every case. We tried to get a number of opinions, a number of backgrounds represented, and we dove in. Again, when someone says to you, "You should do a consensus document," I'm one of those headfirst people. I'm like, "We're doing it, I'm in," I get home and I'm smiling, I'm like, "We're doing this consensus document," I sit down on my computer, I'm like, "How do we do this?"

We went back to other consensus documents that were done. In the cardiology side, we had the American College of Cardiology, that has done several AUC, and then a society called Sky, as well. We looked at how they did that. Again, we set up some basic rules. We had to set up the framework for how the survey would be put together, and we had to create criteria, including that anybody on the writing committee can't vote. On the voting committee, no one could be, obviously, reimbursed, no one could know each other.

I had to go through several rounds to meet consensus. Then, it came down to-- How do you structure an appropriate use criteria for IVUS? And then I can probably pull 10 people in a room and say how to use IVUS, and everybody uses IVUS differently. So, one of the secret sauces in the whole project was creating three phases where we were like, "Let's focus on three important procedural parts of your intervention, where IVUS is utilized, could be utilized, or should be utilized, and we'll use it as a framework.

That was probably what I was most proud of out of this, because we created this pre-intervention phase, which was a step through on the corner side, you get the wire crossed, and then you IVUS, and now, you're evaluating again, where's a healthy reference vessel, what's the diameter? Is there a clot in the mixed plaque? That's a pre-intervention phase. We have the procedural phase, which was-- Okay, I'm going to balloon, and if it doesn't yield, I'm going to IVUS, see what I want to do next, if I want to stent.

If I debulked with atherectomy, I may go back in and make sure I did a sufficient job. Then, the post-procedural optimization phase is-- I put a stent in, let's just make sure that stent's well opposed, no complications. I've got a small dissection, let's just take a look at it, make sure it's not extending back into the media or adventitia, that I feel like I need to cover. That was probably the breakthrough with the whole document. That is probably the most under-recognized out of the whole thing.

[Dr. Sabeen Dhand]
Is that format, or that form-- You can say, is that available to other people? Could I go in my practice and have a little regimented way of how I use IVUS? You're right, all eight IRS in my practice, either some of them don't use IVUS, some of them do, and then there's some, like me, who use it all the time, but variable, even within myself.

[Dr. Eric Secemsky]
Yes, absolutely. I mean, if I could say I have one career goal, is to get all of us, me, you, all of our colleagues, vascular surgery, vascular medicine, to do superficial anything that we do in the peripheral vascular space, to get it to be done a little bit more consistently in the more standardized approach. One of the table in there, in the consensus document, walks through these three phases, and it talks about different clinical scenarios that you're looking for in each phase.

Honestly, out of all, you can cite the appropriateness, and we'll get into that in a minute, but if anything, if you're a new user, just following that first part is really helpful to standardize how you use it. Again, that's how I use almost every one of my IVUS cases now. There's always somewhere-- something happens, and I vary from it, but I would say 80%, 90% of the time, I'm doing the pre-intervention run, I'm doing the middle run, I'm doing my post and that's how I use IVUS. I think everyone in that committee agreed on it.