Bret N. Wiechmann, MD, FSIR, FAHA, FSVM spoke about the management of tibial artery disease at the 2019 International Symposium on Endovascular Therapy (ISET). He sat down with Vascular Disease Management to discuss current options for treatment, his personal approach to treatment decisions, and upcoming technologies to watch.
What is the current state of treatment options for tibial artery disease?
It is a dynamic time for tibial artery intervention. There have been a number of technologic advancements that have been helpful, but there is still more work to be accomplished and additional data needed. It remains a challenge for physicians and industry to come up with the right technology to give us durable results.
What are some of the issues with mixed data?
As surely everyone is aware, the recent meta-analysis by Katsanos and colleagues has raised important questions about drug-eluting devices. One of the drug-coated balloon trials, the IN.PACT DEEP Below the Knee study, was halted due to significantly higher amputation risk seen in the DCB arm. There are some conflicting data there though. However, although the IN.PACT DEEP trial was halted, the Lutonix BTK study shows a clear benefit. Where does the truth lie? Those are two ends of the spectrum and the truth is probably somewhere in the middle.
Do you have any comments on the use of atherectomy?
Atherectomy has been criticized due to a lack of solid data. There has not been a study that has been done with atherectomy as standalone therapy — atherectomy has always been complemented by angioplasty, which confounds the evidence. It is hard to know how much benefit is derived from the atherectomy device vs the adjunctive angioplasty. I believe atherectomy makes intuitive sense in that removing plaque in the artery is likely to lead to a better outcome. I think more data should be sought and obtained, but it might not take the form of a pure, randomized, controlled trial.
What data are available on atherectomy with and without drug-eluting technology?
As mentioned, there are few data in terms of atherectomy by itself. The recently published LIBERTY study had a subset that showed a significant benefit to patients with CLI, especially the most severe Rutherford 6 patients, using orbital atherectomy with angioplasty. It still had the angioplasty component though. There are some studies in the works for combination therapy of atherectomy plus paclitaxel below the knee, or drug-coated balloons and drug-eluting stents below the knee, but the studies are not complete, so it is too early to draw conclusions. It is important that we show that there is clear benefit in terms of limb salvage to these patients.
How are you personally approaching treatment decisions at this time?
We do not currently use below-knee drug-coated balloons because we are not currently part of a clinical trial. Our procedure of choice depends on the nature of the disease that we are treating. If we see heavy calcification, then atherectomy is utilized first, followed by angioplasty. We only use off-label, coronary drug-eluting stents below the knee when absolutely necessary, even though there is good evidence that shows that in short lesions they tend to do better than balloon angioplasty or bare metal stents.
Given the challenges surrounding the current data, what steps are being taken to arrive at a better solution?
The amount of interest in this space is a positive development, as we did not approach this problem aggressively for a long time. With attention comes reflection on what was done, what is currently available, how we are going to practice on a practical level, and what will happen in the future. The number of patients with CLI is likely to grow, based on an aging population and people living longer with chronic manifestations of diseases. Additionally, there are all kinds of interesting technologies in development and a great deal of creativity in this space. We might not have the right atherectomy device yet, or the right drug. We are reaching for the stars, and I think that is what is needed.
Are there any new technologies you are closely watching?
The Temporary Spur Stent System (Reflow Medical) has generated a lot of interest, though it is not yet FDA-approved for use in the United States. It sort of resembles a blowfish and is meant to deliver the agent of choice deeper into the wall of the artery to reduce restenosis. Additionally, there are stent-like technologies with the Tack Endovascular System, and there is a micromesh stent undergoing a trial right now.
Do you have any tips for colleagues in terms of choosing a treatment strategy?
Some of the choices we make are based on our own personal successes and failures with particular wires, catheters, etc. Sometimes those decisions are made for us through purchasing groups and hospital contracts. I think that if you have a handful of devices and some options available for tricky situations, then it is not necessary to have every product made by every company.
Any final thoughts on tibial
I am excited about where we are with tibial artery intervention. So much attention has been on this space in the last 10 years, and we now know more about the impact of CLI and the impact of amputation. Groups with a singular focus on CLI are helping create awareness around this epidemic, including general public education, working with governmental agencies on a specific CLI diagnosis code, and of course, continued physician education and research. There are centers that are focusing entirely on CLI intervention, because it is not possible for everyone to take it on. Treating CLI takes a lot of time and effort, and blood, sweat, and tears. People who practice in that area must be passionate about it.
Disclosure: Dr Wiechmann is on the clinical events committee for the Lutonix BTK clinical trial.