Hello, my name is Christy Willocks and I'm going to talk about peripheral heart disease. This is module one. These are my disclosures. So in this module, I'm hoping that what we'll learn is recognize the underlying pathophysiology of peripheral heart disease, be able to identify patients with peripheral heart disease, what their symptoms and exam would be like, and then look at different types of testing and how to apply that testing to a plan of care. Here are some additional references if you really want to dig in. So peripheral heart disease, it is most commonly underdiagnosed and not very well treated in the US and worldwide. Recent studies show that fewer than two-thirds of primary care routinely screen for peripheral heart disease and only 6% were aware of treatment guidelines. So unlike your colonoscopies and your mammograms, things that primary care providers usually look for, peripheral heart disease is not really on the radar. Public awareness of peripheral heart disease is also fairly low, between 21 to 61%. And even though awareness and screening is fairly low, it is the third leading cause of atherosclerotic morbidity following coronary artery disease and stroke. Prevalence is estimated to be somewhere around 238 million. Again, it's very underdiagnosed, so it's very hard to get an accurate idea of how many patients have peripheral heart disease. Critical limb ischemia is felt to be about 11% of all cases. Those are the more severe cases. You compare that 238 million to the 244 with ischemic heart disease, as well as the 89 with strokes per year. The cost burden is felt to be about 6.3 million per year. Cost burden in the US of hospitalizations alone is estimated to be at 6.3 billion per year. A few additional facts for peripheral heart disease. Estimations in America are 8 to 12 million have peripheral heart disease. This affects one in three diabetics greater than the age of 50. Smoking increases risk greater than 400%. So if I had a room of providers in here that did nothing but peripheral vascular disease, I would say most of us would say if you have a patient with peripheral heart disease that doesn't smoke, it's almost unheard of. Maybe one, two, or three patients that you can think of. There are over 150,000 limb amputations every year in the US. Amputations are bad enough, but the problem with a patient with an amputation is that only 50% of patients live four years post that amputation. If you have peripheral heart disease or one big system, that also increases your risk of cerebral vascular disease by at least 70%. So what are your risk factors for peripheral heart disease? If you're used to working in primary care or cardiology, these are not new things to you. Diabetes of course, renal dysfunction, patients that are older than the age of 50, smoking history, high cholesterol, high blood pressure, family history, as well as your inflammatory disorders and your vasculitis, things of that nature. So my five layer beefy burrito is meant to be funny, but in reality, when you think about what atherosclerosis looks like, it's a very similar picture of what we kind of do to our bodies with time and genetics. Atherosclerosis leads to micro and micro dysfunction within the vessel wall. So to explain that a little bit further, nearly all atherosclerosis is caused by the interaction that we have between the intima. Remember your pathophysiology days, which is the innermost part of our artery and the interaction it has with the blood and what is happening to the innermost part of the artery. So for things that can cause that intima become injured, first you have mechanical stress. That is your stress in general and high blood pressure. You have your high blood sugar, your cholesterol. Those are things that can affect that innermost layer may cause disease. You have environmental factors such as smoking that damage that innermost layer as well as genetic factors as well. So what happens when that vessel wall becomes injured? It has several major consequences that lead to issues with our health. One, it can cause stenosis. Of course, stenosis means flow limiting blockages and that can become occlusive. Two, when the not only the intima becomes damaged, the middle part of the artery can become damaged in week two and that's what leads to an aneurysm. And the last is embolization. That's when the vessel wall is damaged and it kind of forms a little scab or atheroma. And when those kind of release, that can cause embolization. So in all of those ways, when that vessel wall becomes damaged, that's how we develop atherosclerosis in the end points of what happens to that. Why do we care if a patient has peripheral artery disease? Because the risk of amputation, the patients may not heal very well. It's a very strong predictor of death and other cardiovascular events. It can decrease their quality of life and their mobility. And this is my favorite one here. If you get nothing on a patient, no fancy cardiovascular testing, CTA, stress test, anything like that. If the only thing you get on a patient is ABI, it's ankle brachial index, and that score is less than 0.9, that is associated with a two and a half times increase for MI. So it's a very simple, easy test that you can do. That's a real marker for cardiovascular disease as well. So what are the symptoms of peripheral artery disease? It usually starts out as claudication. Claudication is I take off walking, I have pain in my thighs or my hips or my calf muscles, I stop, I feel better. That is the definition of intermittent claudication. Now to confuse things just a little bit, claudication can also be neurogenic. Neurogenic claudication tends to come more from spinal stenosis. If patients have more advanced disease, that's when they usually have rest pain. They may have sores or ulcers. They can also have numbness and weakness, muscle pain, cramping, fatigue, two classification systems, which are Fontaine and Rutherford. And there's four stages of disease, asymptomatic, claudication phase, critical, and acute ischemia. We are less likely as interventional people to help patients with their symptoms if they have evolved to weakness, neuropathy, and swelling. Those are things we don't often make better, but they are symptoms that you want to look at and kind of differentiate. So this is your Rutherford stage and your Fontaine stage. They go zero to six. One has the Roman numerals, one has regular numbers. And again, you go from asymptomatic all the way down to severe ischemic ulcers or gangrene. And of course the goal here is not to get to level six. So just a quick review of anatomy. Your heart sits here. We have our descending aorta and then your aorta. Off of our aorta comes our renal arteries, our bowel arteries, our mesenteric arteries. Then we break off into our common and external iliac arteries. About the time that we hit our groin level, that's where we have our common femoral artery. And that extends, our SFA extends from the common femoral artery all the way down to the popliteal, which is behind the knee. And then we have three vessels that supply our foot. Those are the anterior tibial, perineal, and posterior tibial artery. Now on this diagram, coming out here to the side, this is our profunda. Now this is one of my favorite vessels because I try to explain to patients that that is your lifeline. If you lose your superficial femoral artery through stenosis, that the profunda is the thing that's going to help us most get collateral flow down to the bottom part of your leg. So just a quick review of your anatomy there. So let's talk about taking a history. The first thing that you want to ask the patient is how active are they? How far can they walk? Are they getting up and walking a mile a day, a half a mile? Are they on the couch? When they do walk, where do they hurt at? If it's in your hips, that may mean inflow and iliac disease. If it's in your thighs, again, upper level disease or the pain in their calf, which would be more SFA disease. So where did the symptoms occur that gives us a good idea of where the blockages may be? What does the pain feel like? How long does it last? Pain that comes on with walking is classic for peripheral artery disease. Pain that feels better with rest is classic peripheral artery disease. You want to review their medical history. Do they have all the risk factors? What have the patients noticed about the appearance of their legs? Have they lost the hair on their legs? Are their legs shiny? Are their nails thick? All of these are classic things for people with arterial insufficiency. Have they had ulcers or wounds in the past? And then my favorite question, and I'll say this probably more than once or twice in these slides, are your symptoms lifestyle limiting? Do you have to stop what you're doing because your legs hurt you? And that's a good clue that that patient would benefit from a procedure. So physical exam, we start with palpation. And I would like to say that I check pulses in all of these locations every visit. But I think realistically when you're doing an exam on a peripheral vascular patient, you for sure want to listen and feel their carotid arteries, feel their brachial radial arteries, and then of course their DP and PT pulses are all important things to feel for. Also, you want to listen over the carotids for bruise. You want to listen for even subclavian bruise as well as abdominal bruise, renal bruise, and then common femoral. All those are good places to not only feel, but listen. You want to look at their legs to see if they have pale legs, blue feet, dependent rubors, skin changes, or ulcerations. And if you're blessed enough to have a Doppler device in your clinic, you want to listen to those DP and PT pulses. And if you get just a monophasic flow, that gives you a little bit of clue versus a multiphasic sound that that blood flow is a little bit better. The easiest test though, if you can feel the pulses with your fingers, they're generally doing pretty decent. So if the patient comes to you with ulcers and you're not exactly sure what you're looking at, these are a few pointers about how to identify what type of ulcers they have. If it's a venous ulcer, which account for about 70% of all ulcers, these tend to be large, shallow around the ankle. They can be painful, but these venous ulcers occur because of the venous blood is pulling around the ankles and that blood is desaturated. There's not a lot of oxygen down there. And so it tends to cause the tissue to break down and develop these ulcers. You want to look at these patients to see if they have sign of chronic venous disease, as well as they may have some hemocyterene staining or discoloration in their legs. Those are also good clues to figure out that that's a venous ulcer. Now arterial ulcers on the other hand, tend to be more around the toes or the distal part of the foot. They like to be perfect little circles. They can get fairly deep. The foot will usually appear pale and these are extremely painful for the patients, unless they're a very bad diabetic. Even the little tiny ulcers they get between their toes tend to be very painful, as opposed to some of the venous ulcers, while uncomfortable, don't tend to be as painful as arterial ulcers. You'll notice that the pulse exam is not normal and people that have arterial ulcers are at increased risk for limb loss. So diabetic ulcers, again, they tend to be on the foot area, kind of like the arterial ulcers. They tend to be deep. There's sometimes a callus around there and these patients can develop cellulitis. Diabetic patients don't always feel these ulcers and they don't even know when the ulcer began because they don't have that sensation. Mixed ulcers are a combination of all three or two and that's what we see a lot of time is that the patient may have venous disease, but they also have arterial disease and you tap onto that a little bit of diabetes. So it makes it kind of a more difficult wound to treat. So in these pictures here, I want you all to be able to identify that the pale leg and the bright red leg belong to somebody with arterial insufficiency. So a patient with arterial disease, when their legs are elevated, tend to look pale. When they let their legs down, they develop something called dependent rhubarb because that blood is filling that leg back up. So you see that on exam, when you put their leg down, that they'll have that bright red state occur. Now, as opposed to our venous patients, they'll have swelling, they'll have thickness of their skin, they'll have that hemocytin staining that you see there. And then you can even see the impressions of where she has been wearing her compression stocking. So it was a dead giveaway on that one, but that is the difference between these two sets of legs. Now, if you're examining a patient, I'm going to assume that this patient is either in an urgent care or emergency room. And if you see someone's leg that looks like that, everyone should immediately kind of jump on and say, I know what that is. The five P's of acute limb ischemia are something that absolutely cannot be missed. Pain, power, paresthesias, paralysis, and pulselessness. This is not usually just a little bit of pain, but this is writhing around in the bed kind of pain with associated neurological and sensation changes that happen within so much of not having blood flow. So if somebody comes to you and maybe you're primary care, or maybe you're even in the vascular world, and we've kind of ruled out peripheral heart disease, what are some other things that as a healthcare provider we should be thinking about? So I'm gonna go through a list here. Is it venous disease? Again, we looked at some changes that occur with venous disease. Venous disease is much more likely to cause swelling and discoloration. Do they have pain behind their knee? Do they have a Baker's cyst? Can you see that? Can you feel that? Do they have compartment syndrome? Usually when I see compartment syndrome, it's a very acute end that occurs after a procedure, but patients that are very active and young in exercise can have some swelling in their muscles that can cause some pain as well. Is it spinal stenosis? They can also have pain withstanding. They can have weakness. The pain can be positional. Do they have a nerve root compression? Arthritis, foot or ankle arthritis, connective tissue disorders? Popliteal entrapment is usually you're young people with a popliteal occlusion behind the knee, and that's where the anatomy has pushed in on that artery. Do they have a bursitis or do they have neuropathy? And the difficult thing with most of these patients is sometimes, yes, they'll have peripheral artery disease, but as we get older, we might get one or two of these other problems too. So trying to differentiate what is actually causing the patient the most pain will help get the best treatment plan. So testing for peripheral artery disease, ABIs, that is an ankle brachial index, and that's where we compare the blood pressure in the upper arms with the legs. Very easy test, very good initial screening test, little risk to the patient. Some people do complain that the cuffs are tight, but most people survive that pretty easily. The limitations of an ABI test is that sometimes when we have atherosclerosis or calcified arteries and we squeeze that artery, I tell patients our artery kind of pushes back, and that's just because the artery is stiff. We will get a reading that will be way above one or we'll get a reading that'll show non-compressibility. What we can do in those situation is add ultrasound to see where the blockages are, and we can also add TBIs because that can be very helpful in a diabetic patient. TBI is a toe brachial index where we really take the blood pressure on the toe itself. With just a plain ABI, when we get it at the ankle and the arms, it's a little bit difficult to see the exact location of the blockage, but if we get PVRs, which with segmental pressures, we can start at the top of the leg, do cuffs all the way down the leg, and that will help you see exactly where you think the blockages may be, and of course there's arterial duplex, and that's just ultrasound of the arteries. So on this chart, we have what is normal and what is abnormal for our testing with ABIs and TBIs. Now there's some other information on here. Your transcutaneous oxygen pressure and your skin perfusion pressure are things we do more so with critical limb ischemia, so we'll kind of push those off to the side. We want our ABI to be greater than 0.9, and we don't absolutely want it to be less than 0.5. So somewhere in the middle is what I call our gray zone of when it's best to treat patients. Now, we certainly treat patients with critical limb ischemia, but that's a whole different kind of treatment scheme there when they're in that danger zone. Same thing with our toe pressures, above 70% is where we want them to be. We want them not to be less than 0.4, so that kind of just gives us a range of disease without being in the danger zone. So in 2016, the AHA and ACC came up with some decision trees to kind of help us figure out how best to triage patient with abnormal ABIs and with claudication. So this first one here is for a patient with claudication and suspected peripheral artery disease. It breaks it up into three pathways. If the patient has non-compressible arteries, again, that's because the calcification has occurred, then you wanna move on down to your TBIs. If your TBIs are abnormal, then you wanna start treatment and maybe further testing. Same thing here kind of in the middle where you've got this, well, it's kind of normal to borderline. If you have a normal to borderline test, the next step there is to do an exercise ABI. And then again, you can go on down the pathway to treatment and additional testing. If your ABI is for sure abnormal, exercise ABIs are the next thing limited. And then again, you come back around there to your treatment and additional testing. Now, a different pathway here is for your suspected critical lemischemia. These are your patients that already have rest pain, wounds, or gangrene. It breaks it down exactly the same way with your ABI being the very first test that you get on these patients. You go down either non-compressible or you go down to your toes. ABIs in the middle, where it's kind of in your moderate range, where you go down to some of your perfusion assessments because these patients already have tissue breakdown. When you get to the abnormal range, then you wanna look at your TBIs, some skin perfusion pressure, some additional imaging to help you figure out how best to treat the patient. So let's look at some examples of ABIs and tobrachial indexes. So in this first particular case here, you can see here where right off the bat, the very first cuff, the patient has a blood flow of 81%, left side's at 1.2. So we go down from 80, but before we get down past the knee, we get to 61%. And then at the ankle, we take the highest of these two, which would be 52%. So 52% is not an ischemic zone, but it's not very good. But if you go down this pathway here, we would suspect that this patient has iliac disease and probably also some popliteal to infrapopliteal disease. On this side, you would make it down to about here where you would say probably has some distal vessel disease because that's where you see the drop off. Again, this particular patient had ABIs we were able to obtain, but the TBIs also give us a little bit of additional information. In this particular situation, same thing where we see immediate drop off at the level of the thigh. Then you have a little bit more here. By the time you make it down to your ankle, you're in the 60% range and 30% on the toe. But this is the one that I don't want anybody ever, ever to miss. This ABI is zero. That is never good, unless the patient for some reason doesn't have that extremity. But you start out with a little bit of waveform up here, but by the time you get down here, there's zero waveform. So that would be an emergency. If this patient's in your office, they need to get to the emergency room. ABI testing with exercise, very similar. You will start out with a normal resting score on this right leg. And then you have the patient either exercise on a treadmill or you have them do lifts with their foot. You want them to kind of pump that gastrocnemius muscle. So in this particular situation, you can see you start out great on the right side. It drops just a little bit with exercise, but all within the completely normal range. The left side, we start out a little bit abnormal at 71%, but then we drop down to 34%. So when this particular patient comes to your office and says, man, after about two to three minutes of walking, I'm really cramping in my calf or my thigh. And you can say, oh yeah, I can see that. You can completely see that. And the next numbers are your recovery. How long does it take them to get back up to what the resting score is? So again, a very helpful testing for these patients. When you get past your ABIs, you get past your PBRs and your exercise scores, and you decide that this patient may need intervention, the next thing on your pathway are gonna be either MRA testing or CTA testing. The type of test you choose may be dependent on your area and what tests they do more commonly. So an MRA is preferred at some institutions. It's got good picture quality. It is less affected by calcification of the arteries like CTA. It does not give the patient radiation, but people with anxiety do not like MR machines. If they have a non-device compatible pacemaker or ICD, then they're not a candidate for MRA. If they have contrast issues or elevated creatinine or low GFR, even with the gadolinium, it's not recommended to do those types of tests on those patients. MRs tend to be more costly and time-consuming, and you do get a little bit better image quality for the most part below the knee, but again, that completely depends on the facility and what they're used to doing. If a patient already has a stent, I would not get an MR just because if you wanna see if the stent's occluded or not, you're not gonna get a good image with your MRA. CTA, on the other hand, I would say is more commonly ordered. Again, the biggest issue with the CTA is that if you have calcium, and we'll see some of that on one of these examples, it just kinda looks like chunks. It gets very hard to see what's going on underneath the calcification. It is sometimes difficult to evaluate collateral flow. It's another test that you have to worry about, renal issues in diabetic patients because of the contrast that we give the patient. And it doesn't provide any hemodynamic information, but that's why I always say start with the ABI because if you have a CTA that shows 80% blockage, you really don't know how flow limiting that is or how much the collaterals are helping you out without the ABI piece of information. So peripheral angiograms would be our last option for testing. It is the gold standard, just like a heart catheterization is for coronary arteries, although again, CTAs and things like that are evolving. If you wanna see vessels below the knee, the angiogram is the most accurate for that. And it's also the best clinical tool for wound-directed revascularization, meaning you take that picture and you can see exactly what artery is going to that part of the foot where the wound is, and so then you can treat in that particular area. It's the only one of these tests that allows you not only to take a picture, but then you can also do intervention. Angiograms, as we all know, are invasive. You have to have groin access and or radial access, and you always have to worry about your contrast nephropathy. Let's talk about a couple of case studies. This patient is 61. She has a prior history of carotid endarterectomy. She quit smoking two years ago, which is a victory. She's been a diabetic for 25 years. She does not have any history that we know of coronary artery disease, but we know she's at risk. She has a history of breast cancer and COPD. She worked in a bakery. She enjoyed her work. She presented with three-month history of pain in the right hip and her upper thigh. Classic symptoms, a walk, it hurts, it gets better, but she felt like her symptoms were keeping her from doing what she wanted to do. Testing included ABI 0.5 on the right, which again is abnormal, and normal on the left. So in this particular patient, our next step was to get a CTA. And you can see here in this picture, she had a little iliac stenosis slash occlusion here on the right side, something that's relatively easy to fix with stenting. And then another view of her CTA, these are the slice-by-slice views that those are sophisticated CTA readers look at more commonly, but you can see where the left side is open and you can see where the right side has some feeling defects there. And this lady went on for intervention, did well, and now is still working in her bakery. So another type of situation. This patient is 81. He does have a history of coronary disease, hypertension, high cholesterol. He's still smoking. He's not a diabetic. He's had a history of alcohol use. And usually when he comes to the hospital, he'll have some DTs and rough up on the nurses a little bit. He presents with a several month history of mixed claudication. When I say mixed claudication, that means it's not your classic just walking out of hurt, but sometimes you have the nerve pain and soreness and different things that may not all be just vascular. He's been able to stay active despite his symptoms. His ABIs at rest were completed. So in this particular patient, he was running at 61% on the right and 54% on the left. So given some of his symptoms that they were mixed, other health conditions, problems with going into the hospital, we decided to go for medical therapy. We told him to start walking. We told him to stop smoking and take statin and plethora. So we follow this patient closely in three months and we decide we'll do another set of ABIs to see if all of these things are making any difference for the patient. So instead of seeing the patient get better, we saw that the ABI had dropped down to 0.35 down in ischemic level on the right and down to 0.4 or 0.39 on the left. He now presents with rest pain and he has a wound on his foot. He's still smoking and he's not gonna walk because he just didn't want to. So what do we do next? So this particular patient would fall now into the chronic limb ischemia family. And a lot of times if the patient presents with rest pain and a wound, despite originally not wanting to be aggressive, is usually more of a candidate for intervention. And this was his CTA. Again, not the best picture here, but you can see just tons, tons, tons of calcium on the outside of this artery. You can see when part of this vessel is missing, that means it's occluded, but he got intervention and did get better. So in conclusion, peripheral artery disease is a problem. It's often undiagnosed. We wanna be sure that we do an appropriate exam and history on these patients so we're actually able to tell who has peripheral artery disease and then appropriately order testing for them so we can get them to the next stage, which is treatment. So for additional references, see this slide here, and or if you wanted to do some additional reading. And then if you have any questions about this presentation, please email academy at medaxiom.com. Thank you.

peripheral artery disease

underdiagnosis

atherosclerotic morbidity

risk factors

early detection

diagnosis

intervention