An Update on Critical Limb Ischemia With Cynthia Shortell, MD

Cynthia Shortell, MD, is the chief of vascular surgery at Duke University Medical Center. At the 2015 VEITH Symposium, she moderated a session on critical limb ischemia (CLI), one of the most important and controversial topics in the vascular field. Dr. Shortell spoke with Vascular Disease Management about current trends in CLI therapy today.

VDM: How have you seen CLI therapy evolve over the last couple of years?

Shortell: That’s a great question. In fact, of all the disease we treat as vascular surgeons, I think critical limb ischemia is one where we have moved the needle the least. From the days of long leg bypass to today with all of the sophisticated balloons and stents, the angiosome concept, and better medication, our limb salvage rate isn’t all that much better than it was 25 years ago. 

That being said, especially with what we’re seeing this year at VEITH, some really exciting new concepts hopefully will help us improve limb salvage and reduce morbidity and mortality from interventions that are related to limb salvage for critical limb ischemia.

One of the biggest focuses during the session that I’ll be monitoring this afternoon is the angiosome concept. The angiosome concept was first developed by plastic surgeons to help them with flap coverage for wounds. The angiosome is a 3D unit of tissue including bone, muscle, nerve, and skin, supplied by a specific artery and drained by a specific vein. The idea is that if we target a certain blood vessel that will be most effective in healing. 

Some surgeons believe in the angiosome concept, while others believe that it is much more important to pick the best appearing target vessel, as we vascular surgeons have been doing for many decades. We’ll be hearing some of the experts in the field today debating some of the pros and cons of the angiosome concept and hopefully outlining where it has the greatest benefit to help patients.

I also think the angiosome concept will become more and more important as we push the envelope on lower-extremity tibial interventions with drug-eluting balloons, drug-eluting stents and other advanced technology. We still don’t know what’s the best treatment for tibial disease. We’re still trying to decide whether an endovascular-first approach for everybody is the best way to go or if some patients are better served with operative bypass right off the bat. 

The BEST trial, which is an NIH-sponsored trial currently under way comparing endovascular and open treatment for CLI, will help us answer that question. The study will compare the effectiveness of best available surgical treatment with best available endovascular treatment in adults with CLI who are eligible for both treatment options. I’m sure we’ll be hearing about the BEST trial results in an upcoming VEITH meeting. 

VDM: Any other study results that have been particularly exciting for you in terms of CLI research?

Shortell: Another really exciting development in the treatment of CLI is on the pharmacotherapeutic side. There’s a new antiplatelet agent that’s an add-on to our current armamentarium of medical therapy called Vorapaxar, which has just been approved by the FDA. 

The exciting thing about Vorapaxar, presented by Dr. Tony Comerota here at VEITH, is that it is the first antiplatelet agent that has been shown not only to reduce the risk of stroke and myocardial infarction in patients with PAD but also to reduce the incidence of limb loss and major adverse limb events in patients with PAD. This is really revolutionary and extremely exciting for patients with critical limb ischemia. 

VDM: In terms of therapies that are being used for CLI, do you think there will be more of a trend toward tibial or pedal access or do you think that will end up not being viable?

Shortell: I think that tibial pedal access is going to be used more and more. It’s clear from the presentations that we’ve heard here today that it’s very helpful in crossing long lesions and tibial lesions. It’s even been presented today as an adjunct in crossing long superficial femoral artery lesions. I think that one of the things that Dr. Veith brought up that’s very important in these advanced techniques is that technical expertise in any given procedure is really key. 

That’s why a meeting like this is so fantastic because we have the world experts in the field sharing their knowledge, experience, and tips on how to do this successfully. I think tibiopedal interventions are here to stay but, as I mentioned, it must be done by those who really know how to do it, because it has the potential to harm the patient if the access vessel becomes occluded. Those who are doing it frequently and doing it well have been able to successfully perform those interventions with a minimum of complications.  

VDM: What is your opinion on the concept of the CLI center of excellence and centers specifically dedicated for just CLI therapy?

Shortell: I think it’s a fantastic idea. I think patients with CLI and PAD in general really do need the team approach. They need the medical therapy. They need people who can offer every tool in the toolbox from pedal access to any type of intervention to open bypass and management of all of their risk factors at the same time: a team that can really support them. We know these patients have many health issues and sometimes some socioeconomic issues, so without a doubt, a team approach is the way to go.  

Cynthia K. Shortell is professor of surgery, associate professor in radiology, and chief of the Division of Vascular Surgery at Duke University Medical Center in Durham, North Carolina.