Interventional techniques can help limit amputations among CLI patients
Peripheral artery disease (PAD) stands as a formidable challenge in modern healthcare, with its advanced stage, critical limb ischemia (CLI), posing a significant risk of limb loss and patient mortality. While there are more than 400 leg amputations daily in the United States due to CLI, there is a beacon of hope in the form of new interventional techniques to restore blood flow to the foot and lower leg.
First, awareness needs to be raised among patients and referring physicians. When a patient has leg claudication and wounds on the feet and legs that do not heal, it may be time to consult interventional cardiology, interventional radiology or vascular surgery for options, explained Kumar Madassery, MD, director of the peripheral vascular intervention and critical limb ischemia (CLI) program at Rush University Medical Center in Chicago. He sees a large number of CLI patients from the Chicago South Side and West Side neighborhoods who are primarily Black and Hispanic and come from low-income households. These populations are hit disproportionally across the U.S. and account for the majority of leg amputations due to CLI. Major amputations also carry an overall mortality rate of 70% within three years.
"Most of the patients that we get that are diabetic, they have renal failure, they have blockages with heavy calcium either in their femoral arteries or below the knee, which is more common in the smaller vessels. Now that's where it gets tough and it gets tricky," Madassery explained.
He said angiograms are usually performed to determine if a patient is suitable for referrals. Many patients with end stage renal failure or diabetes do not have any targets in the foot to connect to via surgery or by complex endovascular procedures. These used to be called "no option patients" and there was nothing anyone could do for them. But that is now changing.
New tools and techniques enable interventions on previously untreatable CLI patients
"In the last five years or so, some of us around the world have been doing a new procedure called deep vein arterialization (DVA), where we can take an artery and connect it to a vein. By doing that and directing the blood flow, we've seen about 60-70% limb salvage in patients that were told they were only going to get a major amputation," Madassery said.
Interventional physicians also have become more comfortable below the knee using various endovascular wires, catheters, sometimes atherectomy devices to debulk heavy plaque burden to allow balloon angioplasty or the use of stent if needed. Intravascular ultrasound (IVUS) is regularly used to better size the vessel, understand the plaque and vessel pathology and detect vessel dissections to enable improved outcomes.
"IVUS really tells us what's going on inside a vessel. What kind of plaque is it? What is the size of the vessels? These kind of tools and techniques have made us perpetually better at getting better perfusion to the wound site," he said.
Madassery is part of an awareness campaign launched in 2024 by the PAD Pulse Alliance to help the general public learn more about this topic. The alliance includes the Association of Black Cardiologists (ABC), Society for Cardiovascular Angiography and Interventions (SCAI), Society of Interventional Radiology (SIR) and Society of Vascular Surgery (SVS), groups that partnered to curb the escalating rates of amputations through education and advocacy.
Retrograde access helps enable revascularization is the toughest patients
The advent of retrograde pedal and tibial artery access in the foot and ankle also offered a paradigm shift in below-the-knee interventions. The technique called subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) was developed in 2012 as a method for the recanalization of low limb chronic total occlusions (CTOs) when subintimal angioplasty fails. Retrograde access is usually obtained via the popliteal, distal anterior tibial artery (ATA), dorsalis pedis (DP) or distal posterior tibial artery (PTA).
Madassery emphasizes the pivotal role of retrograde access in overcoming the challenges posed by intricate tibial lesions. He said it is used in more than 60% of CLI patients in his practice.
Improved physician collaborations are needed
From both a business and patient outcomes standpoint, more work is needed to raise awareness among physicians and patients about PAD and CLI. Knowledge of resources available and where to get a second opinion is also needed.
"We need a lot of hands-on deck to catch PAD early to manage it and treat them appropriately. But whenever something's out of your purview or something you're worried about or can't be done, we need to feel more comfortable asking for help from each other as colleagues and help the patient do better. We see far too many patients left to find us on their own," Madassery explained, adding that physicians need to "do a better job of creating that easily accessible network."
He said patients also are part of the problem because they do not realize how serious CLI is. He said they often have every excuse in the world that the hospital is too far away.
"But if I told a family member they have cancer, they'll say, 'I'm going to Mayo.' It doesn't matter how many flights or how much money it takes, they're going there. But when someone tells them they have CLI, they'll say, 'yeah, okay, cool, but I can't make it downtown. It's a lot of busy streets.' So we have to change that narrative," he said.
Advice for hospitals considering CLI programs
Because there are many entry points into the heal system for these patients, Madassery said it needs to be a collaborative effort to build a CLI treatment program. This includes collaborations with primary care specialists, outpatient clinics, wound clinics, endocrinologists, interventional cardiology, interventional radiology and vascular surgery.
"You need to make sure you have a team, wherever you are. You can start with the team. And there's nothing wrong with having a collaborative team to discuss options, do angiograms or do workups or consider bypass, but at least talk together. If something is beyond the scope of what can be done there, that's when you should easily reach out to your colleagues," he said.