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Limb Salvage: Management Of The Limb At Risk

Dr. Niren Angle discusses peripheral arterial disease and the treatment options that are available.
Limb Salvage: Management Of The Limb At Risk
Featured Speaker:
Niren Angle, MD
Dr. Angle specializes in: Limb salvage and peripheral arterial disease; including treatment with endovascular and open surgical techniques, venous insufficiency, and thrombolysis, carotid disease & stroke, mesenteric ischemia, aortic aneurysm, dialysis access, thoracic outlet syndrome, and aortoiliac disease and management.
Transcription:

Prakash Chandran (Host): With peripheral arterial disease or PAD affecting eight to 12 million people in the United States, it's important to not only know about the signs and symptoms, but also how to protect limbs that have been affected. Today, we're going to talk with Dr. Angle, a Vascular Surgeon for Dignity Health.

This is Hello Healthy, a Dignity Health podcast. My name is Prakash Chandran. So first of all, Dr. Angle, it is great to have you here today. I just want to start with the baseline question of what exactly is peripheral arterial disease?

Niren Angle, MD (Guest): Peripheral arterial disease is really an umbrella term for anything that afflicts arterial circulation particularly as we get older. And in its most pure form, it involves a lot of different things and it might involve aneurysms, which is a ballooning out of the artery. It might involve certain autoimmune conditions, which affect the arteries, but principally, when people talk about peripheral arterial disease, the most common presentation of it, is plaque buildup in the arteries, which then restricts blood flow to the leg or to the foot. And then ultimately, in its worst manifestation can result in gangrene, amputation, ulcers, infections and things like that. So, when people speak about peripheral arterial disease in the most generic of ways, that is what they're referring to.

Host: Okay, so when we think about a person that might be at risk and when it actually manifests, can you talk to us a little bit about that?

Dr. Angle: Generally it's a disease of the aging population and you can put it into two or three buckets. So, there's the aging population that is afflicted with diabetes, particularly insulin-dependent diabetes. Then there's another population of patients who have renal failure. They're on dialysis. And the third group is patients who have generalized atherosclerosis, which is plaque buildup in the arteries, not related to diabetes, not related to renal failure, but related to either smoking or their genetic predisposition, which is the most difficult one of them all because you can't affect that. It causes plaque buildup on a more accelerated rate than one would expect for any given age. And all of those buckets that I just described, they're not necessarily discrete buckets.

If you think about a Venn diagram, there's a significant amount of overlap between those three or four. But generally speaking, it is patients who either have a very bad set of genes that predisposes them to severe arterial disease, or they have insulin dependent diabetes, which can affect significant number of patients in terms of limb loss.

And then there are the renal failure patients. And then you talk about other things such as genetic predisposition. In particular, African-Americans are up to four times more likely to have an amputation than non African-Americans. The diabetics of those who have a lower extremity, meaning leg amputation, more than half of those will require a second leg amputation, meaning the other side within two to three years.

So, it's a very pervasive limb condition. And there are two components to it. One is the treatment of the leg itself in order to make sure that they don't lose their leg. But the more compelling part of it is that if you just look at patients who have peripheral arterial disease and who don't have any manifestations, such as gangrene or ulcers or wounds that are not healing, and yet they have PAD; then those patients also are likely to have coronary artery disease and cerebrovascular disease causing heart attack or stroke. So, peripheral arterial disease is actually a marker for patients who are going to die of either heart attack or stroke. And so, it is incumbent upon physicians to identify those patients and treat them more aggressively or as aggressively as possible as far as risk factor modification. That is quit smoking, hypertension, glucose control, weight loss, all of these things that affect not just the limb, not just the leg, but also the heart and the brain.

Host: Okay. That's really good to know. So, when you talk about the physician being proactive in treating this, I do want to get to treatment options. But before that, I just want to learn a little bit about if people that fall into the buckets that you're talking about; if they're for example, diabetic or they smoke, do they need to get proactively screened for this? Or is this something that will just start to manifest symptoms? And then they go to see their provider?

Dr. Angle: Yeah, that's a great question, Prakash. The screening part, there have been multiple organizations and initiatives looking at screening. And I must admit having been involved in some of them, it's a very low yield in terms of actually finding patients who need treatment in the sense of a procedure to fix their legs. But where it is important, is that it identifies those patients who need to be more aggressively treated. So, the short answer to your question, having given you a long answer already, is yes, they need to be screened, but the screening is not something that is very complicated and the screening is very easy.

The screening is done in a doctor's office with just a blood pressure cuff and a Doppler ultrasound machine, which is a handheld machine. And you get what's called the ABI, the ankle brachial index. And basically what that does is it measures the blood pressure at the ankle and indexes it, or compares it to the blood pressure of the arm. And with normal unobstructed arteries, your index, your ratio should be about one, meaning that the blood pressure in the arm and blood pressure and the leg is the same. When you start getting blockages in the legs, to use the layman's term, you start getting a decrease in that index, in that ratio.

So, instead of one, it will be 0.7 or 0.6 or 0.5. And the lower that number gets the lower that ratio gets, the more significant the obstruction is in terms of the blood flow to the foot; and the more likely it is that the leg is going to get into trouble. It's also important to recognize that just because you have peripheral arterial disease and maybe a decreased ankle-brachial index, you don't need to get treated for that.

There are people who will advocate angioplasty and angiograms, just because somebody has blockages seen on ultrasound or demonstrated on a screening exam. That's wrong. You only treat the legs if they're symptomatic. And symptomatic means they have an ulcer that's not healing. They have gangrene, they have pain in the foot that is so severe that they can't sleep at night. All of these are reflections of critically reduced blood flow. We call it critical limb ischemia means reduced blood flow and not adequate blood flow. And if that's the case, then further diagnostic modalities and treatment options may be considered.

But other than that, just because you have PAD, doesn't mean your legs need to be treated. Because you have PAD, you do need to be more intensively managed as far as your blood pressure control, your blood sugar, control your weight control, the cessation of smoking and all of the sort of "heart healthy" or generally anti-inflammatory modalities that one would like to use in order to ensure better health.

Host: Okay, that makes a lot of sense. And you touched on this a little bit around how just because you have a PAD doesn't mean you necessarily need to get treated and you should be expressing certain symptoms. Gangrene is one of the things that you mentioned, what are some other things that a person can look at to recognize that they may have the symptoms that require treatment?

Dr. Angle: The most common presentation of peripheral arterial disease is something called claudication. Claudication basically refers to a set of symptoms that are as follows. When a person walks a certain distance, after a given amount of distance, they have calf pain described as either pain or aching or tightness and they can't walk any further.

Then they have to stop. They don't necessarily have to sit down. They have to stop. And then it goes away. Then they start walking again and again, they can only walk that same distance. It's a very predictable and stereotype presentation. And other things can cause leg pain when you walk, if you have back problems and the nerves are pinched, that can cause back pain, but the difference is with arterial disease, it's always the same distance every single time.

And if you have that and you're seen by somebody who knows how to manage or diagnose it, then it can be called claudication and claudication does not require treatment unless it's so severe that the patient cannot function. And there are a lot of people who undergo procedures that are unnecessary and it's been shown over and over again, that if you have claudication of a certain kind and that's where you need a Vascular Surgeon or a specialist to, to kind of fare it out the details. But generally speaking, if you have claudication, if you just embark on a walking program, meaning that you walk to the point where you get that discomfort, and then you walk through that pain and you do it once or twice a day, regularly, you'll double your walking distance without any procedure, without any surgery in about six months. So, what Vascular Surgeons advocate is that if you have claudication, we try to stay away from doing angioplasty or stenting or any of the procedures that are so ubiquitous because it's not necessary.

And it can actually initiate a series of events that makes your life, makes your leg worse over, over time, because then you start getting what's called re-stenosis, which is a blockage of the area, which you ballooned or which you stented? So, generally speaking, if you have claudication, it's best to avoid procedures. If you have gangrene or pain when you say sleep at night, which is called rest pain, or if you have an ulcer or a wound that develops on the foot or the leg, and it doesn't heal; then that's a better reason to be aggressively investigated as far as what the underlying anatomy is and see if there's something that needs to be done to fix it. But that requires a well-trained set of eyes and a person who has really sober judgment about what to do and when to do it. Not everybody needs to have something done just because you have a narrowing of the arteries in the legs, particularly.

Host: So, just to summarize, if you're experiencing the claudication, as you were mentioning, just a walking program to kind of overcome that distance limitation once or twice a day is really all you need. But if it's something that is more severe, like gangrene or you have those ulcers, then it's time for the treatment that you're talking about. Is that correct?

Dr. Angle: You encapsulated beautifully. Absolutely. These are the official recommendations of the Society for Vascular Surgery, which is our biggest organization in the world.

Host: So, when we talk about the treatment options for those that need it, that are expressing those symptoms that are more severe; can you talk a little bit about what is available to them?

Dr. Angle: Yeah. If you looked maybe 15 years ago, the only thing available was a surgical bypass where we actually make an incision above and below where the artery is blocked and we bypass it either with your vein or with a synthetic graft taken off the shelf. And obviously that's an operation and we tried to avoid it as much as possible unless it was really necessary.

And I'm talking about for claudication patients. For non claudication pain those let's talk about the ones who really need the treatment. The first step is to have a set of diagnostics. It can be a CT scan. It can be an MR angiogram or it can be what's called a regular, we call that a catheter-based angiogram where it's like the same angiogram you have for your heart, except we're looking at the blood vessels in the leg.

And if we see a narrowing or a blockage that we can advance a wire through, then we might treat it with a balloon angioplasty or a stent. Rarely what's called an atherectomy, which is trying to shave the plaque, which really hasn't been demonstrated to be very beneficial. But nonetheless, those are the three modalities in stepwise fashion, which you can use to treat it.

The advantage of it is that there's really no downtime. You have your procedure, you go home and then you're up and about the next day without limitation. The downside is that it's not as durable as a surgical treatment would be because anytime you angioplasty or stent a vessel, it can incite a reaction which causes scar tissue to build up and you get what's called re-stenosis.

And there've been lots of advances such as drug eluting stents, drug-coated balloons, which try to limit or obviate that kind of narrowing from developing or at least getting that severe. And they've had reasonable success, but I wouldn't say it's stunning success. There's an improvement at the margins.

So, that's what we do for patients who have rather limited or easy to treat disease in that fashion. We call it the endovascular therapy. If you have more than that, and you need to have really significant improvement in blood flow to the foot, and you can't do it endovascularly, then we go to surgery and that's where we consider doing a bypass. And well-trained Vascular Surgeons can do bypasses down to two millimeter vessels or smaller into the foot from the groin. So we can, there are patients who have blockages from their groin crease all the way down to the ankle, nothing in between. And those patients are not appropriate for endovascular therapy because likely, technically you won't be able to do anything.

And even if you do, the likelihood of that lasting very long is, is small. So, in that case, if you've got a good angiogram that shows that you can bypass to something, then we will do a bypass. So, it's a bigger operation with a hospital stay, but the results are usually very good in the limb salvage, meaning the ability to rescue the limb from a risk of amputation is very high. So, the advantage about a Vascular Surgeon is that we can do the endovascular approach or we can do the surgical approach. And it really depends on what approach is the best for that particular patient. And that's where the judgment comes in.

Host: I see. So, we've so far been just talking about the leg and I'm wondering if PAD actually affects any other limb besides the legs.

Dr. Angle: Yeah, it's very interesting from a biologic standpoint. It doesn't affect the arm in the same way. The arteries that supply the arm arise out of the chest, arise from the branches of the aorta, which is the biggest blood vessel in the body. And those arteries sometimes can develop a narrowing, but the manifestation of that narrowing, the manifestation of that blockage is typically that there's a decrease in blood pressure on one side or there's absence of blood pressure compared to the other side. It rarely results in gangrene of the fingertips, unless it's really severe.

Now, in that case, when it does, then there are lots of options. Same thing, endovascular approaches to surgical approaches. But it affects the legs significantly more than it affects the arms by orders of magnitude. The other thing about peripheral arterial disease, like I told you at the beginning is that so far we've been talking about plaque buildup and obstruction, but also within that umbrella is a series of or a set of conditions that involve aneurysm disease.

So, the biggest blood vessel in the body, the aorta, can develop an aneurysm, which is a ballooning out. And if it reaches a certain size, then that can rupture and you can die from it. The biggest risk factors for those are genetic background and smoking. And if you combine those two, meaning that you have a genetic background, your father, or your brother, or your mother, or somebody had an aneurysm and you either have one, or you might be at risk for one, so, you should be screened. And you're smoking, then you're virtually guaranteed that aneurysm is going to expand at a higher rate or faster rate than if you weren't smoking. The danger is, it's called the silent killer, because you don't know you have an aneurysm, unless somebody actually either examines you and finds one or screens for it.

And Medicare actually has a program called the Save Act that was signed by President George W. Bush, which entitled somebody who's entering the Medicare program as a first timer, if you're over age 65, i.e. Medicare, and you have a history of smoking or you have a family history, and there are other little sub categories, then you're eligible for a one-time ultrasound scan, which will show you that you do have an aneurysm or you don't have an aneurysm. And if at that age you don't have one, then you can probably stop worrying about developing one. But if you do have one, then depending on the size, you might be either subjected to a surveillance regimen once a year, with ultrasound and or CT, or it may be big enough where you need to have it treated.

So, atherosclerotic disease involves every blood vessel in the body. We talked about the legs. Occasionally the arms. It affects the blood vessels that go to your intestines and can cause significant abdominal pain every time somebody tries to eat. There's all kinds of manifestations of peripheral arterial disease. And it requires really a what I would call a jeweler's eye in order to be able to appreciate the possibility of it and to look for it and to know what kind of tests you might want in order to determine what to do next.

Host: Just as we close here, I wanted to ask if there's anything you can recommend that someone do to really avoid this disease. But from what you've told me, it really sounds like the management of blood pressure, blood sugar, obviously smoking cessation and really any of the things that cause inflammation. That feels like the best thing that you can do and be proactive about number one, am I correct in assuming that, and number two, is there anything that I've missed?

Dr. Angle: You're absolutely correct in assuming it. What I like to tell my patients is you want to live an "anti-inflammatory" lifestyle. And it's too detailed, it's too complex to go into here, but generally speaking, you want to decrease inflammation in the body. And that is by exercise. That is by quitting smoking. That is by being on statins, which are very important to decrease inflammation apart from lowering cholesterol. In fact, I'll have many patients that I'll put on statins even if their cholesterol is normal. And the one thing that we did not touch on, which is probably as critical as anything else, is diet. And most of the stuff that people eat is if it's processed, if it's sugar, if it's the kind of stuff that is constitutes a typical Western diet. And I don't want to say just a Western diet because this is prevalent all over, but it is to reduce inflammation. So, eating things, and there's a ton of data out there, ton of information for the average person to just do a Google search and look up anti-inflammatory lifestyle or foods and fish and certain kinds of nuts, the Omega 3's and the Omega 9's and things like that.

There's lots of stuff that you can do short of medication in order to decrease the inflammation. Exercise is a very important part of decreasing inflammation in the body and diet is a very important part. Do not smoke. Blood sugars. You don't have to be diabetic to have blood sugar issues. There's an entire condition called pre-diabetes, which is not bad enough to treat with medications, but it is a cumulative amount of damage that occurs over the years. So, you know, getting that tested, making sure your weight is down because Americans are overweight and they're overweight by orders of magnitude.

They're not just a little overweight and that obviously increases the likelihood of diabetes, that increases cardiovascular disease. That increases just about everything you can imagine. So, decrease weight, exercise, statins if needed. Watch the foods, don't smoke. These are all common sense items that if you ask anybody they'd go, yeah. But what it requires is really detailed attention to what each of those components are and to live them.   It has to be something you do every day.

Host: Absolutely. There's no question about it. One of my favorite quotes is the "price of peace as eternal vigilance." And that means that every day you have to pay attention, you have to act in a way that is going to be healthy. And in this case really eat that heart-healthy diet, get out and exercise and be safe.

So, Dr. Angle, thank you so much for your time. I truly appreciate it. That's Dr. Niren Angle, a Vascular Surgeon for Dignity Health. Need a doctor? We can help. Visit dignity health.org/ourdoctors to get started. If you found this podcast helpful, please share it on your social channels and be sure to check out the entire podcast library for topics of interest to you.

This has been Hello Healthy from Dignity Health. Thanks so much. And we'll talk next time.