Most Popular Angioplasty Web Site
Stent Center Stent Center
with support from Medtronic Cardiovascular
B. Clay Sizemore, MD, FACC, FSCAI
B. Clay Sizemore, MD, FACC, FSCAI is an interventional cardiologist at Cardiovascular Consultants of South Georgia in Thomasville, a relatively small community of less than 19,000 people. The hospital in Thomasville does not offer cardiac surgery, so very high-risk PCI cases have to be transported almost an hour away to Tallahassee, Florida where there is a surgical heart team.

In this interview, Dr. Sizemore discusses how intravascular lithotripsy (IVL) has been a game-changer for patients with significant calcified lesions -- that instead of having to transport them to a distant hospital, he is able to safely and efficaciously treat them in Thomasville. While he has been utilizing IVL in this manner since it was approved by the FDA in 2021, the guidelines for the treatment of calcified lesions lagged behind. But in January 2023, SCAI revised its guidelines to endorse the use of IVL in hospitals regardless of whether or not they offered surgical backup.

    B. Clay Sizemore, MD
Clay Sizemore, MD

Q: When we started Angioplasty.Org over 25 years ago, one of the very first posts on our Forum was from Dr. Tom Aversano, who was doing the Atlantic C-PORT study to compare outcomes of PCI done at hospitals with and without surgical backup. So the question of performing PCI without surgical backup has been a topic of study for quite some time. Can you speak to the evolution of this in your practice?
Dr. Sizemore: Sure. We were fairly early to the game. Actually Dr. Aversano played an integral role in initiation of our PCI program back a little over 12 years ago as part of Atlantic C-PORT. We started our PCI program as a part of that trial and early days were challenging because of one out of every three patients ended up being randomized to the non-backup center; that's back in the day when 30% of all the PCIs were done at the quote unquote surgery on-site facility. So we had to make that as efficient as we could.
But it was still super inefficient and fairly unsavory to the patients and patients’ families to have to go to the next town over and have interruption of care between the diagnostic cath and the PCI. And so it was, at the end of the day, all very much worth it to get a good data set to make everybody comfortable that we were doing the right thing. And, as you know, the results came out very much in support of the safety of doing PCI in non-backup centers with experienced operators.

We completed the trial and transitioned into a grandfathered PCI program. The number of patients going out was drastically reduced. But we did make a commitment to the state of Georgia at the time to adhere to the enrollment criteria for the trial because that's where the data were in terms of safety and appropriateness. So we continued to transfer out “high risk” cases. That means we took them to the backup center, which is down the road in Tallahassee. But it was it remained hugely inconvenient and it resulted in a limitation of our availability for access to patients in South Georgia when we had to go out of town and spend several hours to go and do a case or two at a time.

But over time, procedures continued to evolve, and the equipment got better and better, and we became facile with the transradial approach and same day discharge and those kinds of things, and, I think, like most centers started to include some of those more intermediate risk patients, lower ejection fractions, the occasional left main cases that didn't require mechanical support.

Most recently, until the advent of IVL, we were pretty much only taking patients with very severe calcified disease down [to Tallahassee] because of our commitment. We made the decision after many meetings to not intentionally bring in a piece of equipment that would be “off label” in terms of atherectomy devices and both for medical legal reasons and just for safety, because we know that there is some increased risk with those procedures. So that was the rationale that until we could establish that it was reasonable to be doing calcium modification, we would take those patients to the backup hospital.

Q: And the hospital in Tallahassee with surgical backup is about a 45 minute transport?
Dr. Sizemore: That's right. The ambulance ride for same day intervention, down to the tune of how many thousands of dollars that is and the inconvenience and interruption of the day to go do the same day PCI.

Q: Just for the general population who may not understand this, what are the risks involved in dealing with a heavily calcified lesion?
Dr. Sizemore: The conundrum was always how much is too much calcium and how to try and predict which patients could be reasonably managed with our on-label devices, specifically noncompliant balloons, scoring balloons. And that was pretty much it.

The concern is if you attempt a calcified lesion without the ability to significantly modify the calcium beyond balloon technology, you run the significant risk of the lesion either being non-dilatable, which is the real catastrophe, because then you end up with an incomplete procedure and either have to acutely transfer the patient in a less than stable state with a partial angioplasty alone or an inability to deploy a stent or the somewhat less catastrophic, but nonetheless problematic, situation where the lesion dilates, but we don't really get full stent expansion. Those are both fairly undesirable for long term outcomes and for acute patient experience, not to mention operator experience. So those are kind of the safety issues we worry about.

Theoretically in both of those situations, when you're forced, because you're in the weeds, to go ahead and use larger balloons, noncompliant balloons at very high pressures, trying to maximize the result, with every gradation of aggressiveness you go with the balloon, you increase your risk for perforation or uncontrolled dissection. So those are the kinds of concerns about proceeding without plaque modification.

Q: Right. And to use plaque modification without surgical backup previously has been prohibited or at least not in the guidelines. So what has changed in these new guidelines, because this is a big door opening that's allowing this to be done now.
Dr. Sizemore: Right. I think there's a recognition that the guidelines are frankly probably a little overdue. There is a recognition that more and more patients are being done in non-backup centers because of the geographic need and access, particularly the STEMI care. And there is a recognition that, with experienced operators and adequate volume, calcium modification can be performed. Fortunately, IVL is on-label at non-backup sites, based on how they designed their trials and submitted to the FDA. So that's been a game changer for us, particularly prior to the upcoming guidelines.

Q: So you've used IVL in your institution for a while.
Dr. Sizemore: Yeah. We quickly adopted IVL as soon as it was approved…. We were full on by July [2021], it's a year and a half, almost two years.

Q: And your experience in terms of any concern about not having surgical backup and using calcium modification.
Dr. Sizemore: The experience thus far has been awesome. The good thing is there's really nothing particular or challenging to do in terms of training or the preparation of the staff and stuff like that. It's just another angioplasty for us. So the adoption was smooth and easy and following good protocols. We haven't had any safety issues, consistent with what the data shows, that the incidence of perforations and no reflow and dissections is just exceptionally low. That's been our experience to date.

Q: Given the fact that IVL is obviously quite safe and your experience has been good, do you wind up performing many cases where you're using both IVL and orbital or rotational atherectomy together?
Dr. Sizemore: So we have not, as of yet, adopted atherectomy just because of the off-label nature. I suspect that we'll revisit that for some select cases down the road when the guidelines are out and there's kind of more support for doing it in the SOS [Surgery On Site] Centers. But currently we're not doing any combined therapies. We certainly do that use that technology in the periphery in extreme cases. But no, I'm not doing a lot of combined therapy right now.

Q: You used the term game changer. Can you speak to that and what your experience has been both prior to approval and now?

Dr. Sizemore: Sure. It has a further reduced the number of patients that we have to transfer out of our local market, which is good for patients, good for doctors, good for the hospital. Now pretty much the only patients that would get sent out are kind of no cross type cases that just really have to have a rotational or orbital atherectomy or laser or something like that. So that's an infinitesimally small number relative to the number of patients with calcium. The other thing, as someone who's been in a situation where I have a non-dilatable lesion and, in an attempt to dilate it, we have dissection and yet I can't deploy a stent. That nightmare scenario which, albeit relatively rare, is now a non-issue because we have the ability to treat or modify calcium. So just those two things alone are awesome. I will say that I think that the development of a calcium modification strategy has promoted a revisiting of the algorithm with regard to imaging. And since deploying IVL in the lab, we have really redoubled our commitment to imaging most cases and have recognized that there was really a lot of less than appreciable calcium out there that met criteria for modification based on imaging guidelines. And in those cases I just think that, while we were getting good results before, I think we're getting really maximum expansion and optimizing the final result better than we really ever have.

Q: What is your threshold for turning to calcium modification? You were saying imaging. When you say imaging, are you talking angiography, IVUS, OCT?
Dr. Sizemore: Yeah, all of the above. We implemented the latest generation HD OCT about six months ago. Prior to that we were exclusively an IVUS lab. But we do a mix of IVUS and OCT; we start with OCT if there's no contrast limitations and it's not an ostial lesion, but we are facile with IVUS as well. When we're looking at OCT, we look at the thickness and length and we have an algorithm that we follow pretty closely. We generally will test with a non-compliant balloon unless it's the most severe form. But we go into the case knowing that there's going to be a low threshold for calcium modification. And if they meet certain criteria, we just modify regardless to make sure that we really can get a fully expanded stent and the best possible result.

Q: Right. So intravascular imaging is telling you that there tends to be more calcium than you're seeing on angiography. Is that correct?

Dr. Sizemore: Oh, absolutely. I think especially the situation where you have relatively thin circumferential calcium. Everybody can see the big thick ledges of calcium and boulders that that show up on the fluoroscopy. But with OCT, in particular, we have realized that you can frequently under-appreciate circumferential calcium and long planer calcium that creates the ability to land your stent in zones that are least likely to give you edge dissections.

Q: This goes back to the very beginning of stenting where, using IVUS, Colombo showed that stents were being under-expanded.

Dr. Sizemore: Yeah, the imaging piece can't be understated how much that has gone hand-in-hand with IVL as part of our strategy for getting the best possible final result.

Q: Those are basically all my questions. Any other thoughts?
Dr. Sizemore: Yes, I would applaud SCAI for revisiting and recognizing the critical role that non-SOS centers play in the care of patients across the country. And addressing their unique needs and challenges and supporting their participation in the best quality of care. They should be commended and it’s super helpful to those of us in those settings. We're excited to keep moving forward with delivering better and better care.

Q: Great. By the way, what is the caseload in your institution?
Dr. Sizemore: In 2022, we did 657 PCIs between three operators and that has trended up by 5% or so per year for the last ten years.

Q: Right. And you're in a relatively rural area?
Dr. Sizemore: We are in Thomas County. We serve a six-county catchment area as our primary service area and probably nine counties, including the primary and secondary service areas. So yeah, we are the lone PCI center between three surgical centers that are all an hour-and-a-half, two hours apart.

Q: So, yes, a great need. Thank you so much for your time.

This interview was conducted in February 2023 by Burt Cohen of Angioplasty.Org.