The Role of Serration Angioplasty in Peripheral Artery Disease

[Dr. Aaron Fritts]
Let's jump into that, Peter. Today we're going to talk a little bit more about specialty balloons because I think everybody in the audience knows that there's typical scoring or cutting balloons have been around for a while now. You mentioned in the prior episode the Serration Angioplasty, the Serranator. Can you talk to us about how the specialty balloon space has evolved over time? What is the difference between this new balloon and the prior ones that we think of?

[Dr. Peter Soukas]
Traditionally, I think probably the first dedicated Cutting Balloon on the market was the Boston Scientific Cutting Balloon, which was unfortunately fairly limited in terms of lengths that were available. Today, in fact, they're about two centimeters for the peripheral devices, and the coronary devices are even shorter-length balloons. These were basically three surgical balloons that were just glued onto the outer surface of the balloon. When we're talking about below-the-knee disease these are typically long diffuse lesions. It was really not very practical to treat either above the knee or below the knee with these particular devices.

In more recent years, we had the AngioSculpt balloon, which did have the advantage of coming in 40 and 100-centimeter lengths, but the results were somewhat variable in terms of the acute luminal gain, and the degree of recoil that we typically would see. The newest kid on the block, of course, is the Serranator Balloon, which is really, I think, a fairly unique mechanism of action that uses these serrations, which are able to basically have about a thousand times more focal force than a typical angioplasty balloon.

Why is that an advantage? I think it's able to give us a very predictable and safe expansion of the lumen along these so-called fault lines, and our rates of dissection in recoil are much lower than with the traditional scoring balloons that we've used in the past.

[Dr. Aaron Fritts]
You mentioned one of the issues with prior technologies was recoil, especially in BTK lesions, and also the desire not to stent in the setting of CLI. How does Serration angioplasty help solve for those particular problems? I know you mentioned less dissections, for sure.

[Dr. Peter Soukas]
Yes, for sure. In both the prelude above and below the knee studies, we saw really excellent final luminal residual stenosis of less than 23%, and a typically fairly low inflation pressures of only 68 atmospheres. The dissection rate was really very, very low to the extent that the need for a bailout stent, for example, was less than 2% in the below-knee study and only about 4% in the above-knee study, which I think is pretty remarkable for a balloon technology. It's that predictable response that I think makes it such an attractive tool in our armamentarium, especially for below the knee, where we really, really try to avoid placing stents.

We know that you can successfully implant coronary drug-coated stents, but that's really limited to the proximal third of the tibial artery. What do you do when you're down near the ankle? You can't put a balloon expandable stent there because it'll get crushed. The ability to avoid the need for a scaffold, particularly in the distal two thirds of the tibial artery, I think is a real potential advantage for serration technology, as opposed to just plain-old balloon angioplasty.

[Dr. Aaron Fritts]
You brought up a good point. I heard a talk by Edward Gifford at the recent sharing cross talking about, there was maybe a study released recently about using it below the ankle. Is that right?

[Dr. Peter Soukas]
Yes, that's true. One of the nice things about the technology is that because it's not rigid, stainless steel blades, it has the flexibility that you can take it around the corner into the common plantar, and in fact, into the dorsalis pedis or the medial or lateral plantar vessel. That's again, I think an advantage compared to the older focused force angioplasty technologies.