"This is not an area for the dabbling interventionalist," Parikh explained. "The speciality has evolved such that many of us interventional cardiologists care for patients with extra-coronary vascular disease, whether it is carotids, mesenteric visceral disease or lower extremity disease."

He said PAD as a specialty has evolved over the past decade. This includes the publication of multidisciplinary guidelines that outline the technical and cognitive skills required. He added that the skills one needs are completely achievable, but as a developed specialty area, it requires a high level of commitment.

"You have to know not only how do the intervention, but when, and when to stop, and how to care for these patients. The technical skills overlap tremendously with what we do in coronary interventions," Parikh explained. "It seems easy to say it is just the procedures that are different, but it is more than that."

In the coronary space, for example, it is easier to explain to a patient what their options are and know when it is best to refer that patient for bypass surgery. With PAD, though, such things are more challenging.

Parikh said there are a lot more interventional cardiologists than there are other specialities that also can perform these procedures. There are also a lot of patients in need of treatment.

While a lot of sessions at cardiology meetings these days pertain to structural heart, and it appears that is a major direction of interventional cardiology today, Parikh said he believes there is actually a larger procedural volume to be found in PAD and CLI.

"As coronary volumes are declining in many places, these other procedures are well within our skill set, and are opportunities for procedural growth and programatic growth, but it does require careful attention to detail," Parikh said. 

How many patients have peripheral artery disease?

Parikh said statistics show about a third of cardiology patients have PAD, but it is often under diagnosed. He said cardiologists will often say maybe 5-10% of their patients have PAD, but he said this is because they are not looking for PAD hard enough. 

For that reason, he said there is often a need to educate physicians in a practice to be more vigilant for PAD. "The patients are there and their need is unmet," Parikh said.

Multidisciplinary peripheral vascular care team

The heart team concept that evolved a decade ago with the introduction of transcatheter aortic valve replacement (TAVR) is expanding to other areas of vascular medicine. On most heart teams, there is an interventionalist and a surgeon who reviews patients together and determines what therapy is best for that patient. 

"That happens less in the vascular domain because much of the work is done in a silo. The patient goes to a specialist and that person offers them the therapy they can provide and then discharged from their care in a single silo," Parikh said. "I don't think that is the best way to care for some of these complex patients. But that has been the norm for for quite a while. I do think that we could learn a lot from that heart team approach."

However, he said, a big part of the heart team approach is the sharing of revenue, and that is a challenge in the vascular space. The mandated heart team for TAVR procedures requires a surgeon and interventional cardiologists to be involved in the care of the patient, but there is no such mandate for other areas of vascular care.

"If the healthcare system was different, that approach might be tenable," Parikh said. 

A step forward in this sort of vascular team collaboration was seen in the landmark, late-breaking BEST-CLI trial presented at AHA 2022. It involved both surgeons and interventionists and is the first large, randomized trial to look at whether vascular surgery or endovascular revascularization is the best strategy in CLI. The study showed both approaches to be safe and effective, but surgery came out a little ahead in long-term outcomes. 

Parikh said the trial data will be helpful in offering more informed decisions for CLI care, but he was only able to enroll a small number of his patients because of the requirements. 

"There are many, many ways to treat patients, and which one is the best is not always clear. The truth of the matter is ... only a handful of my patients qualified to be candidates in the BEST-CLI, and the rest of the patients are where I live in the real world. I need a little more guidance as to what is right, and getting another brain to weigh in is always a good thing," Parikh explained.

What is needed to start a critical limb ischemia program

Parikh said the No. 1 thing needed to start one of these programs is to have a champion physician who will head the program and put the time into it that it requires. This will often require advanced training.

The second thing to think about is navigating the politics of the local healthcare environment. Parikh said the clinical referral pathways for vascular care are often highly variable.

"Ultimately, I think good care and quality begets ongoing engagement, and once a dedicated person who is a champion establishes a practice and shows responsibility and works collaboratively, there is no shortage of patients who will benefit from this approach," Parikh said.