Evo Terra (Host): Peripheral artery disease, or PAD, is the narrowing or blockage of the vessels that carry blood from the heart to the legs. Are you at risk? Let's find out, with Dr. John Eidt, the Chief of Vascular Surgery, who is on the medical staff, at Baylor Scott & White Heart & Vascular Hospital, Dallas. This is HeartSpeak from Baylor Scott & White Heart & Vascular Hospital. I'm Evo Terra. Thanks for joining me today, Dr. Eidt.

John Eidt, MD, RVT, RPVI, FACS: Glad to be here.

Host: So what is PAD and why haven't I heard about it before today?

John Eidt, MD, RVT, RPVI, FACS: Yeah. So PAD stands for peripheral arterial disease. And that naturally brings up the question of what's peripheral, what's arterial, and what's a disease? So peripheral basically means not central or not in the middle of something. So peripheral means out there. So basically we have to do just a little bit of talk about your circulatory system.

So, as you may know from high school anatomy, the heart is the central pump in your plumbing system, and attached to that are arteries, which carry oxygenated blood out to the body. And the veins collect that blood after the oxygen and the nutrients have been taken out and takes that blood back to the heart and lungs to restore the oxygen and pick up some more calories and whatnot, and then go back out to the body.

So you have this constant circle from the heart through the arteries out through the veins and back to the heart, and that's what circulation stands for. So, the peripheral arteries basically means not arteries in your brain or intrinsic to the heart itself or special blood vessels like pulmonary arteries or portal vein that goes through the liver. So for the most part, what we're really talking about from a practical standpoint, is the arteries that carry oxygen to your legs.

Host: A ha.

John Eidt, MD, RVT, RPVI, FACS: PAD for the most part, while it could affect your arms, typically we reserve the term PAD for lower extremity peripheral arterial disease. That by far and away is the most common use of the term PAD.

Host: Got it.

John Eidt, MD, RVT, RPVI, FACS: So peripheral arterial disease, it's not inevitable, but it's very common as you get older. It does seem to be associated with a variety of lifestyle factors. For instance, there are some places in the world where for not entirely understood reason, there are populations of people who just get very little PAD.

Naturally, we jump to think, well, it must be dietary because people have discrete diets in different parts of the world. And there probably is a component that is dietary. There's clearly a component that probably is genetic. Your parents have a huge impact on who gets this problem, and there's probably some physical factors like activity, how much activity you undertake, and what kinds of activity you undertake.

We'll get into that a little bit more. But it is true that in North America, we tend to see this as an age related problem that's connected to the other kinds of things we see as we age; joint problems and blood pressure issues and peripheral arterial disease is kind of part of that package of getting older. Our blood vessels tend to become stiffer with time. When you're young, your arteries, the aorta for instance, is almost as big as a garden hose in diameter. It's the main blood vessel that carries blood out to your body, and particularly down to your legs. And when you're young, it's quite elastic, and it changes diameter quite significantly with each pulse, with each beat of your heart, that bolus of blood that gets pumped out of the heart kind of stretches the aorta, and the aorta, because it's got so much elastic in the wall quite rapidly contracts, or it springs back, and as it springs back to its normal shape, it delivers that blood out to the body, so you have a, it smooths out the pulsatility. So if you had stiff arteries, like if your arteries were made of PVC, like pipes, and your pump is intermittent.

So your heart is pump pump. If you have stiff arteries, your blood pressure would go up, and then it would drop to zero, and then it would go back up, and it would drop to zero. And the same thing would happen to you. You would become conscious, and then you'd go unconscious, and you'd wake up and you'd go back to sleep.

But because your arteries are elastic, and they can absorb some of the energy from the pulse wave, they absorb that energy, they stretch, and then they give that back as the artery contracts slowly between beats, and it smooths out your arterial pulsation, so you have more or less constant flow to all your organ systems where you're burning fuel. So as you get older, though, the inside of these arteries, two things happen. One is the arteries become a little more stiff. The elastic, just like in the waistband of your underwear, wears out over time, your arteries do the same thing. They become less elastic, so they don't stretch quite as well.

So what that does, unfortunately it causes your peak blood pressure to actually seemingly go up. Your heart's not doing anything different, but because your arteries are stiffer and they can't relax to sort of absorb that pulse, the systolic blood pressure gets higher as you get older. So where we'd like your blood pressure to be 120 over 80, that's the systolic pressure of 120.

The diastolic pressure is when your heart's relaxed between pulses. We'd like to see your blood pressure varying between about 120 millimeters of mercury down to about 80. That's a very typical kind of normal blood pressure. As you get older, it's very common to see your systolic pressure creeping up. Even though your diastolic pressure may still be 60 or 70 or 80, the systolic tends to get a little higher just cause your arteries get a little stiffer. The second thing that happens is, and it's almost an inevitability if you live in North America, which it relates to our diets and our activity levels and our tendency to use a lot of cars and transport modes rather than walking around a lot.

There's a tendency to build up plaque. And I'm just going to use a general term, plaque, which is kind of like corrosion or rust that builds up in a galvanized pipe. You build up junk on the inside of the artery and it restricts the flow of blood. So where you might like to have an artery that's wide open, you may wind up with 50 percent or 60 percent of the inside of the artery is now instead of carrying blood is full of kind of plaque that's restricting flow.

And that restriction in flow leads to symptoms because you don't get the blood supply where it needs to go. What happens to people that develop plaque and plaque, we don't really know exactly what contributes to plaque, but we think the main factors are genetics. If your parents have had heart disease, you might well have it. If your parents have hypertension, you might well have it. So it's hard to change your genes. So you're sort of stuck with who you are. You can't change your parents.

We think things like your cholesterol is a component. It's been heavily advertised and a lot of pharmaceutical companies have made lots of money off of treating cholesterol. And it's clearly a component in the picture, but it's not all or none.

Host: Right.

John Eidt, MD, RVT, RPVI, FACS: For instance, I have patients who we know that smoking, for instance, is a pretty important contributor. You can't just treat cholesterol and keep smoking and you know you can't just up your statin and still smoke. The impact of smoking is so significant that it's almost not even worth spending the money on a statin if you're going to continue to smoke because it has such a toxic effect on the inside of your blood vessels. Because what it does, it kind of creates inflammation.

Inflammation is a general term that describes the response of the body to injury. If you get burned, your skin responds by becoming inflamed. If you twist your ankle, your ankle swells, and that's partly a component of inflammation. So it's not an infection, but it's the response of the body to a variety of injurious agents and and toxins like cigarette smoke and some of the chemicals that are in cigarettes injure the inside of the blood vessel and irritate it.

Not to like, for instance, one analogy I sometimes use is people say, well, I want to stop smoking. Can I just cut back? Will that help my arteries? It turns out that there's not a very good dose relationship with cigarettes and peripheral arterial disease. That is, it is true, the more you smoke the worse it is. But, if you've ever laid brick, you've used a steel bristle brush to brush in between the mortar to clean out the bricks. If you took that brush and you just rubbed your forearm a few times until you scraped the, got it nice and raw and you just kind of rubbed the hide off your forearm, and then you left it alone for a while, never touched it again, within a few days, it would completely heal itself, and you wouldn't even be able to tell you'd had a abrasion. But if you come back tomorrow, and all you have to do is take that brush and just stroke it one time, and it stays irritated.

And the next day, you never let it heal. You irritate it again with one cigarette and the next day, one cigarette. So once you get it inflamed, even a small dose will continue to keep it and keep the inside of your blood vessels inflamed. I use that analogy to encourage people. I would never say, well, don't, you know, if you can cut back, it's better than not cutting back on cigarettes.

On the other hand, really the way to do it is to stop because again, every day you have a cigarette, you're taking that steel brush and rubbing that forearm and it never gets a chance to heal.

 So smoking is bad. Cholesterol is bad. Hypertension is bad. Diabetes is bad. That's the main group of factors that you can control. You can't change your genes, but you can change those other things.

How would PAD present? If you're sitting at home how would you know it? The most common symptom is pain in your legs when you're doing something. Essentially, the pain comes from running out of fuel. Think of gasoline in your car just like oxygen in your blood vessels. If you do more work, you need more gasoline. If you're driving a car at a steady speed and you go faster, you burn more fuel. It's just like if you walk faster, you need more oxygen. If you put on a backpack and carry more weight, it's just like putting a trailer behind your car, you're going to burn more gasoline because you're doing more work.

If you walk up a hill, it's going to take more work to do that. And you're going to burn more fuel if you're going up a hill than if you're on a steady ground. The most common symptom with PAD is work related leg pain. If you do the same amount of work, you should get the same amount of pain.

What's important about that is, there's no such thing as a good day and a bad day. If your pain in your legs is due to poor circulation, every time you walk the same distance at the same speed is going to result in the same burning of fuel. Now, there are other leg pains. Ringling Brothers figured this out a long time ago. It's the three ring circus of leg pain. Leg pain is either due to circulation problems, neurogenic problems, nerve problems, or it's due to musculoskeletal problems. In other words, and musculoskeletal just simply means the structural elements that make up your leg. So muscle, tendon, cartilage, bone, fascia, all the stuff you're made of.

If you get inflammation in your hip, that means your hip joint is irritated, you're going to get pain from it. If you pull a muscle, you tear your hamstring, you're going to get pain from it. If you tear a cartilage, you get pain from it. So those are structural things. So historically, if you said, well, what's different about leg pain from circulation than from, let's say, a musculoskeletal pain?

Well, one of the things that I ask people is, what's it like with your first step out of bed in the morning? Musculoskeletal pains are almost always worse first step out of bed in the morning. You know, when you've played basketball and you twist your ankle during the game, it wasn't too bad. You went home that night, you went to bed, it wasn't too bad.

Got up the next day, try to take a step and it's, oh my goodness, it's quite inflamed and it takes a little while to get going. As you get older, like me, getting out of bed in the morning, it's no fun. Your back is you're all kind of locked up. It takes a while to get those things moving. Musculoskeletal pains tend to improve as you lubricate your joints and get moving. So that's sometimes a helpful way to sort of figure out what kind of pain is this. Neurogenic pains, like from a slipped disc, there's really two general groups of neurogenic pain. One would be like a neurospinal pain, something from your back, a slipped disc, a pinched nerve in your back.

Those tend to be unpredictable. You may know certain kinds of things you shouldn't do, but they come and go. They'll have good days and bad days. Sometimes your back really hurts, sometimes it doesn't. You take some ibuprofen, things are okay, and then you'll have an attack where it hurts you. So that sort of intermittent pain is more typical of neurogenic pain. And the quality of the pain tends to sometimes patients will use terms like shooting pain, like an electric bolt going down your leg.

So, circulatory pain, it's very important because a lot of doctors don't know the three ring circus of leg pain. You might have diabetic neuropathy, meaning your peripheral nerves just aren't working very well. And if that's the case you may have a burning pain that's not circulatory at all, but somebody might treat you for what they think is really a circulatory problem.

So it's important for even just a consumer to know leg pain, musculoskeletal, neurogenic, circulatory, and if you do circulatory treatment for a neurogenic pain, that won't work. Fixing your hip, if your circulation's bad, isn't going to do you any good. So that's pretty important.

Now, if you have peripheral arterial disease, how would you know it? Well, one would be some people have some degree of blockage in their arteries, but they have compensated for the blockage and they don't have any symptoms whatsoever. In fact, probably a lot of us do. I'm sure I've got some plaque in my arteries. I've seen ultrasounds of my legs when I was looking for other things and see, there's a little plaque. I can see a little calcium that showed up, but I don't have any symptoms because my arteries have correspond when the plaque builds up, the arteries can dilate a little bit and accommodate a little bit of plaque.

So you may be asymptomatic. You can detect this by doing what's called an ankle brachial Index or ABI. The Ankle Brachial Index compares the blood pressure in your arm to the blood pressure in your leg. And since, like we said before, most PAD affects the legs more than it does the arms, we use the arm as the denominator. This is the normal blood pressure we assume. Let's say your arm blood pressure was 120, but you check your blood pressure in your foot and it's 80. We would say your ABI is 80 over 120, or what is that, 0. 66, I think. I don't do the math that well. But you basically just compare your leg to your arm.

Your leg pressure should be actually a little bit higher than your arm blood pressure for some more complicated physiologic reasons, but a normal ABI is anything above 90 percent or 0. 9. If you went to your local doctor and they just screened you, just checked the blood pressure in your arm and your foot simultaneously, and you were less than 90 percent, we would say you had asymptomatic peripheral arterial disease.

Now, why would we want to know that you have asymptomatic peripheral arterial disease? If you're not having symptoms, who cares? Well, the reason is people who have peripheral arterial disease, whether symptomatic or not, are at higher risk for cardiac vascular disease and cerebrovascular disease. That means you're at higher risk for stroke and heart attack. So that even though your legs are not bothering you, it's a great, cheap marker for potential risk of having a heart attack or stroke in the future. And it's one of the reasons we encourage our primary care doctors to check the blood pressure in the arm or order it in a vascular lab. The so called ABI, and if the ABI is reduced those might be people that you want to spend more time focusing on risk factor modification, that is blood pressure, diabetes, cholesterol, exercise, and smoking cessation, because they're at a little higher risk for stroke and for heart attack.

Now, the other thing I don't want to do is paint a grim picture of PAD. Peripheral arterial disease is very common. You know, and you get my age, I'm 69. By the time you're in your late 60s, probably 25 percent of people, especially in North America, have some degree of PAD. Many of them are asymptomatic and it is important only because it helps to focus them on making sure they don't have a heart attack or stroke by taking the preventive measures that they should.

Now, if you do have pain when you walk, it is not an inevitable downhill course. Not everybody that has PAD will need an operation or need an arteriogram or ever have a risk of a catastrophic outcome like an amputation. Most people with peripheral arterial disease can control their symptoms by risk factor modification, again, treating your diabetes, treating your blood pressure, treating your cholesterol, stopping smoking, and most importantly, exercise. Get out and walk because if you have a blockage in an artery let's say your calf muscle. When you walk, your calf is the main thing you're walking with and you've got a blockage in the artery in your thigh and it reduces the blood supply to your calf. Well, you walk a couple of hundred yards and your calf runs out of fuel.

 The supply and demand are out of link. So your calf doesn't have enough fuel and starts to ache because it builds up a little acid when it doesn't have enough oxygen. And you stop. If you stop walking, you pay back your oxygen debt and then you can walk again. And usually you can walk just about the same distance.

Every time you walk and you get some pain in your calf, the body sends a signal to say, Hey, we need more fuel. Send us more coal down here. We're trying to do some work. And that signal causes your blood vessels to get bigger and to develop collateral circulation around the blockage. And so this is quite similar to if you were driving down the interstate and the interstate highway is completely blocked.

You get off on the exit ramp and you go down the side road and then you get back on the freeway when you're past the obstruction. Well, if you, if that blockage stays there over time, and you keep taking that side road, you can make that side road from one lane into two lanes and it can be a very efficient pathway.

So the exercise is critical. And the more times that you ask for fuel, the more capacity the body has to develop collateral circulation. So I've seen people who had complete blockages in the main artery in their leg who had no symptoms because they exercised. And it's one of those things we were talking about some of these spots in the world where people live a long time and don't get peripheral arterial disease.

One of the things that does seem to be common to many of these locations is people who work when they're old, they're out gardening, they're walking, they're playing pickleball, they're doing things and not sitting on their backside just watching TV. So, getting out and making, remember, we're brain, we're body, soul and spirit, and you can't ignore the body part. You know, the body is what carries us around. So we're all about our intellect and we're about our spirit and all that, but you're still an animal and you got to respect the animal part of you. And the main way to do that is just be an animal, get out and walk.

You can ride a bike, get on a treadmill, swim. It doesn't matter what you do. It's make the oxygen, make your lungs work, make your heart work, and they, your body will respond to that. Now I will say occasionally, and it's a minority of patients, even though you watch television, the advertisements are all about, well, we can do this kind of stent, or we can put this kind of a laser in, or we can do some kind of procedure.

Most people don't need procedures. Procedures are good for doctors, but a lot of procedures are not necessarily good for patients. So you want to be cautious when people start offering to treat things because not everything needs magic. It doesn't need a bullet. Most things don't. But if you do, there are a variety of techniques that are akin to roto rooter techniques, that is catheter-based techniques to clean out your arteries.

Now, we can't clean out everything, but there are certain kinds of arteries that we're pretty good at cleaning out. The more proximal an artery is, that is the closer to the heart; the bigger it is because the arteries grow out just like the branches of a tree, from a big trunk to smaller branches. The bigger the branch and the shorter the blockage, the better the success.

If you have small arteries with long blockages, your chance of getting durable clean outs are not as good because the artery tends to clog back up with inflammation.

Host: Right.

John Eidt, MD, RVT, RPVI, FACS: Stents are very, everybody knows about stents or they've heard the word S-T-E-N-T. Those are like little springs that sit inside an artery to help hold it open.

We can use balloons to crack the artery open, but sometimes we have to put little scaffolding inside to help hold it open. So stents may be a very good alternative for some people. And there's a variety of other treatments that include different kind of drug delivery systems inside the artery to prevent inflammation.

If the catheter-based, catheter meaning like a roto rooter, catheter-based treatment is not an option, there are a variety of surgical procedures that we can do. But again, the thing I would emphasize more than anything is, most patients don't need a surgeon for peripheral arterial disease. Most people need to stop smoking, lose weight, get exercise, take their blood pressure medicine, treat their diabetes, and say their prayers, and they'll do fine.

Whereas, sometimes when you start going to get procedures, it can start a domino effect where you can get into some serious complications from it. So just be thoughtful. I'm not saying that procedures are bad, but just like working on your car, if you get the right job done at the right time, it's great.

But if you don't get the right thing fixed, you won't get a good running car. And it's the same true when you go to the doctor.

Host:

Yeah, yeah. Well I think everyone is going to like the good news for many people who are able to change this on their own. So solid news. Anything else to add?

John Eidt, MD, RVT, RPVI, FACS: There was only last thing I was going to just mention, and I really appreciate your time talking to me this afternoon, is the idea of who takes care of these people, right? There's a lot of different doctors and the problem is there's so many of us, we don't even know, I don't even know what some of these specialists do, you know, it's crazy and we're all in our own little boxes. But, vascular surgeons even though we use the word surgeon, I would say probably of what I do on a day to day basis when I see patients, a good fraction of my patients never get a procedure. They're treated medically. We identify the problem. We can have a conversation about what their goals are, we can talk about how to achieve them, and they never get a procedure.

Probably of people who do get procedures, probably two thirds of those are now catheter-based. That is, as a surgeon, I do essentially what I would call radiology. I mean, in other words, we never make an incision. We put a needle in, and we use a variety of different minimally invasive techniques. And it's only the very far spectrum of people who nowadays we still have to do open conventional surgery.

And we still do that for a variety of reasons. And it's still a very effective treatment. What I, what we sometimes get frustrated with, there are some other specialties. I work very closely with a group of cardiologists here, and some of them treat the heart. I don't do heart surgery. And some cardiologists do catheter-based treatment and peripheral arterial disease.

And and many of them do a fantastic job and we overlap in terms of that procedure. And what you don't want to do is have a specialist say to you, well, I've done everything I can, go see a surgeon. Because you may have missed an opportunity for getting the right treatment at the right time first. So I wouldn't look at a surgeon as a treater of last resort, just the opposite. You'd really, I think you want to get the most expert advice you can at the earliest point.

And really the goal is to avoid surgery, to avoid procedures, to avoid any kind of interventions, and to get your blood vessels to work with you for the rest of your life. And most people can achieve that with good cooperation with a caregiver.

Host: Well that's excellent news. Dr. Eidt, thank you for all of this great information today.

John Eidt, MD, RVT, RPVI, FACS: Thank you for working with me. I appreciate it very much.

Host: Once again, that was Dr. John Eidt, the Chief of Vascular Surgery, who was on the medical staff at Baylor Scott & White Heart & Vascular Hospital, Dallas. You can learn more about diagnosing and treating PAD online from Baylor Scott & White Heart & Vascular Hospital, Dallas, Fort Worth, and Waxahachie.

For the name of a specialist near you, please call 1-844-600-2342. Again, that's 1-844-600-2342.

And if you found this podcast episode helpful, please share it on your social channels and check out the full podcast library for topics of interest to you. I'm Evo Terra, and this has been HeartSpeak from Baylor Scott & White Heart & Vascular Hospital. Thanks for listening. Baylor Scott & White Heart & Vascular Hospital, Dallas, Fort Worth and Waxahachie. Joint ownership with physicians.