Evo Terra (Host): More than 3 million Americans are diagnosed with peripheral artery disease each year. To help understand more about prevention, diagnosis, and treatment of the disease, I'm chatting today with Dr. Nirav Shah, Medical Director of MSLC's Cardiovascular Institute. This is DocTalk presented by Montefiore St. Luke's Cornwall. I'm Evo Terra. Dr. Shah, welcome to the show.

Dr. Niravkumar Shah: Thank you for being here and thanks for the opportunity to present certain important topics to my patients and audience.

Host: Well, let's start with the fundamentals for your patients and our audience. Can you give me an overview of peripheral artery disease?

Dr. Niravkumar Shah: So, what it means is that in generalized definition for peripheral arterial disease, it's also known as peripheral vascular disease, and it generally denotes to the arterial disease, not involving the heart and the brain. Apart from that, whether it's arteries of the limbs, the legs, the aorta, the lower extremities, those are the main, you know, consideration and involves something called peripheral arterial or peripheral vascular disease.

Host: Okay, got it. And this disease, what does the disease mean? What's not happening? I assume it means the blood is not pumping through the arteries properly, but I would like you to tell me me me me that.

Dr. Niravkumar Shah: That's correct. So, what it means is that there is some blockages in those arteries. And beyond the blockage, you're not getting enough blood flow. And it translates into the symptoms of the peripheral vascular disease, whether it's something called ischemia, just like when someone is having a heart attack, similar to that in the peripheral vascular system, which supplies the blood flow to the arms, the legs, the limbs, and so forth.

And basically, it's arterial blockage that can cause decrease in the blood flow to the muscles of those supplied territory. So, when that happens, patients are symptomatic. And you know, there are different kind of symptoms, what they feel. But what's important about the peripheral vascular diseases that more importantly it affects the lower extremities. And patients, in general populations, let's say, they are aware of that, but they ignore that. So statistically, I mean, it's underdiagnosed territory of the vascular disease that we need to address to our population.

Host: I understand. Speaking of populations, is there a certain demographic that is more likely to be subjected to this or more likely to be affected by PAD?

Dr. Niravkumar Shah: That's correct. So, let's go back and look at the statistics of the peripheral vascular disease, right? So again, as I said, it's an atherosclerotic disease, just like involving the heart arteries, but it involves the limbs and the peripheral vasculature. And about 10% of the population above age 65 affected by this disease, and also about 2% of the population between age 40 to 60. But, you know, again, more commonly involving the men aged more than 50. And of course, the risk factors are similar to those risk factors for coronary artery disease, such as, of course, advanced age is one of them. But then, the diabetes, the smoking; the hyperlipidemia, which is high cholesterol; sedentary lifestyle, obesity, and all those other risk factors, which again, involves the coronary circulation, coronary artery disease, and causing the heart attack. Similar risk factors are involved in peripheral arterial disease.

But the key here is the symptoms are often ignored. And again, as I mentioned that patients are feeling those symptoms after a certain age, and they think that is related to my old age or it's related to whatever it may be. And it's about more than 50% of the time, it's not reported to their clinician and physicians. So, you know, that's the main reason that is underdiagnosed.

Host: Well, let's talk about those symptoms that are happening because I am not all of those risk factors, luckily, but some of those risk factors because of reality. What should I be paying attention to that maybe I am not now?

Dr. Niravkumar Shah: In medical terms, it's called intermittent claudications. What it means is that when someone is having severe blockages or severe, you know, peripheral arterial disease, what they feel is that severe cramping in the bilateral lower extremity, especially in the calf muscle, when they exert, when they walk, when they take stairs.

When you exert, your muscle require more blood flow. And because of the peripheral arterial disease, because of the blockage, that part of the muscle is not getting enough blood flow, which it requires by demand when you exert, and that's where you're feeling the symptoms of what's called crampings or pain in your muscles. And ideally when you rest for, let's say, about 10 seconds, 20 seconds, less than a minute, your muscle will go back to the resting stage and you restored the blood flow and your symptoms, cramps, pain will resolve. And then when you exert again, you start feeling the symptoms again. So, that's what called intermittent claudication, which is the most common and most important signs and symptoms of the peripheral vascular disease. When you exert, you get pain. When you rest, the pain goes away. And when there's the recurrent exercise or exertion, you recur the pain. So, those are the symptoms.

And as I mentioned earlier, that most of the time we, as a patient, you know, ignore those symptoms and think that, "Oh, I'm getting old, so that's why I'm getting pain." But again, that's something that needs to be kept in mind, especially those patients who have multiple risk factors, such as tobacco use, smoking, diabetes, hypertension, hyperlipidemia. I mean, again, those are the common risk factors that we always want to be under control of.

Host: All right, that's helpful. So if someone is experiencing those symptoms, they would like to go get a diagnosis, what's the process of doing that? Should they just see their general practitioner first? Should they make an immediate appointment with a cardiologist? And if whichever of those, what's going to be done?

Dr. Niravkumar Shah: They have to report to their primary care physician and there is one simple way to diagnose, which is something called ankle brachial index. It's called ABI in a short form. What it means is that we check the blood pressure in our upper extremities and check the blood pressure in the lower extremities. And then based on the ratio of that ankle brachial index, we decide whether patient has a peripheral arterial disease or not. And it's a very sensitive index. So, that ratio should be one or more, but if the ratio of the ABI is less than one, and based on what that number is, we can make a diagnosis of patient has a mild, moderate, or severe peripheral arterial disease. And I can get to that ratio in a few seconds. But again, the most important is to not only manage, but has to understand the symptoms of that, right? And inform that symptoms to your clinician, whether it's a primary care physician, or if you are seeing the cardiologist for some other reason that you are seeing the subspecialist cardiologist. You can mention to them and we can easily diagnose that kind of peripheral arterial disease diagnosis with a simple ankle brachial index.

So, what we do is that we measure the blood pressure in the upper extremity, in the regular way we check the blood pressure. And then, we also check the blood pressure in three different locations in the lower extremities thigh: in the calves, and at the ankle. And then, we take the highest number of the ankle pressure, and the blood pressure on the upper extremity. And then, you know, it's a simple ratio, basically. You know, denominator is your arm and the highest blood pressure at the ankle at the top number, and we can take a ratio. And if that ratio is less than 1, then patient has a peripheral vascular disease. Now, if that ratio is less than 0.9. Then, you have a mild to moderate, anything between 0.4 to 0.9 is moderate and anything less than 0.4 is a severe peripheral vascular disease. So, that's a very simple way to diagnose PAD and that your routine physical examination can do it. And at that time, you can diagnose or you can come to the subspecialist such as cardiologist and we have very sophisticated machine where we can diagnose with the ABI along with the waveforms. It's called PVR, you know, peripheral vascular resistance waveform, that we can, you know, pulse volume waveforms that we can diagnose and see the waveforms dampens when you have a decreased velocity because of the blockage and we can diagnose that way. And this is one of the most simple way to diagnose and very effective way to diagnose the peripheral vascular disease.

Host: Okay. That makes perfect sense. As pressure drops, something is causing that to happen, obviously. That makes good sense. So, let's say-- well, forget the words let's say-- How do you treat this disease? If someone has mild to moderate symptoms versus someone who has severe symptoms, I'm assuming there might be a different treatment paths for that. Can you talk about that for a moment?

Dr. Niravkumar Shah: Again, the treatment starts with the prevention, right? And how we prevent is preventing the risk factor, just like any other cardiovascular risk factor, such as tobacco smoking, diabetes, hypertension, hyperlipidemia. Of course, someone is smoking, definitely we encourage them to stop smoking, because as we know that the smoking can attract the platelet as a clotting factor and worsening the blockage.

Of course, blood pressure needs to be controlled, and diabetes needs to be controlled. So, all those risk factors, of course, we need to manage. But let's see if someone already has a diagnosis and blockage apart from the preventive aspect of it, we can certainly do few things to exactly diagnose where the blockage is and how that needs to be treated. So once we diagnose with the ABI or PVR that patient has peripheral vascular disease and their symptoms, we can do ultrasound of the leg where we check exactly which side, which artery patient has a blockage. We can also do something called CT scan of the abdomen and pelvis with runoff to the lower extremity where we will exactly determine where the blockage is, how much percentage of that blockage has, whether it's multiple blockage or one focal blockage. And based on that information, we can treat those patients.

And the most important thing, just like cardiovascular disease, you have to open that blockage to restore the blood flow so that the patient doesn't get symptoms. And there are multiple ways to open up that blockage by either doing balloon angioplasty, whether you can put a stent, whether you can do an arthrectomy, depending on what kind of blockage. Whether it's the soft blockage, calcified blockage, total arteries completely blockage, then sometimes you may require something called surgical revascularization. Like a bypass surgery, just like open heart, you can do the bypass surgery in your lower extremity to improve the circulation to the distal part of the blockage. So that way, when a patient exerts, they don't get symptoms.

And of course, the medication that you need to take, not only to control your risk factor, but also to prevent further blockage such as aspirin, high-dose cholesterol medications, statins such as atorvastatin or rosuvastatin. So, certain medications are very important for peripheral vascular disease.

But apart from the revascularization and controlling the risk factor, another most important thing is exercise and walking, right? So, the first treatment after controlling the risk factor and before you do the revascularization is the exercise program, whether it's a monitored exercise program or you exercise and walk. So, the more distance you do every day, the better you get because your muscles will get used to it and you get less symptoms.

Host: You know, everytime I have a conversation with you doctors, I am hoping one of you can say I can fire my personal trainer. But it sounds like no, I have to keep working out.

Dr. Niravkumar Shah: So, exercise is very important for generalized health as well as cardiovascular health, which includes the peripheral vascular disease. I think I would say just in summary, that peripheral vascular disease is an underdiagnosed disease, which is very important for patients who have cardiovascular risk factors and very important to keep yourself fit. And if there is any symptoms, to report to your clinicians so that it can be prevented. Or if there is peripheral vascular disease, it can be treated appropriately before it gets to, you know, somewhere where we cannot treat.

Host: Excellent. Dr. Shah, thank you for this valuable information. I appreciate it.

Dr. Niravkumar Shah: Thank you.

Host: Once again, that was Dr. Nirav Shah, Medical Director of MSLC's Cardiovascular Institute. Please visit montefiore.slc.org. Yes, I'll spell that for you. That's M-O-N-T-E-F-I-O-R-E-S-L-C.org for more information about the Cardiovascular institute. If you found this podcast helpful please share it on your social channels and check out the full library of topics of interest to you. I’m Evo Terra and this has been DocTalk presented by Montefiore St. Luke’s Cornwall. Thanks for listening.