New Trends in Preventive Heart Health with Dr. Michael Sills
Dr. Michael Sills provides part one of a series of three podcasts covering topics related to heart disease prevention and living your best heart-healthy lifestyle. The first in the series, titled New Trends in Preventive Care for Your Heart, provides an overview of cardiac risk factors, defines obesity, and the relationship between inflammation and heart disease risk. Associated with inflammatory response, Dr. Sills gives insight into diabetes and the impact of the medication classified as SGLT2 inhibitors. What does cholesterol and your lipid profile have to do with your risk? These tests and inflammatory markers will be also be reviewed.
Featured Speaker:
Dr. Sills is an avid runner, chef and proud grandfather.
Michael Sills, MD
Michael Sills, M.D., a cardiologist on the medical staffs at Baylor Scott & White Heart and Vascular Hospital – Dallas and Baylor University Medical Center, part of Baylor Scott & White Health and the Program Director for the Cardiology Fellowship Training Program at Baylor University Medical Center and Baylor Scott & White Heart and Vascular Hospital – Dallas. Dr. Sills is a board-certified cardiovascular disease specialist. In addition, he has extensive training in echocardiography and vascular imaging and holds certifications from each of those respective boards. His clinical expertise includes general cardiology, echocardiography, valvular heart disease, peripheral vascular disease and preventive cardiology.Dr. Sills is an avid runner, chef and proud grandfather.
Transcription:
New Trends in Preventive Heart Health with Dr. Michael Sills
Maggie McKay: Unless your heart races or you experience shallow breathing, you probably don't think much about your heart just from day to day. But when you do have symptoms, you want to know what's going on and how to prevent that from ever happening.
Joining me today to talk about heart health is Dr. Michael Sills, cardiologist on the medical staff of Baylor Scott & White Heart and Vascular Hospital-Dallas, to talk about the new trends in preventive heart health and more.
This is HeartSpeak, the podcast from Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth. I'm Maggie McKay. Welcome, Dr. Sills. What an honor to have you here. Thanks for making the time. Could you please introduce yourself?
Dr. Michael Sills: First of all, thank you for having me. I'm Michael Sills. I'm a cardiologist. I've been here my entire career and one of my big interests is trying to prevent cardiac issues, kind of prevent coronary artery disease. We see all too much of the aftermath, but it's only been recently we focused more on what we could do to prevent people from getting sick.
Maggie McKay: Well, we are just so grateful to have you here for this first episode of a three-part series of podcasts on cardiovascular health. So today, we're going to concentrate on some of the basics. And the other two, we'll dive deeper into healthy eating and adding exercise into your lifestyle for heart health. And speaking of diving in, let's just start with what are the cardiac risk factors that people need to know about?
Dr. Michael Sills: Traditionally, we talk about five different things. One is high blood pressure. Two is high cholesterol. Three is diabetes. Four is smoking. And five, the one thing we can't do much about, is familial risk of coronary artery disease.
Maggie McKay: That's the scariest, right? Because like you said, you could do all those other things and who knows, if like for instance, both your parents had heart attacks, are you at how much of a higher risk?
Dr. Michael Sills: A lot of that depends on what the other risk factors are. Certainly, there are certain inheritable conditions that predispose you not only for heart attacks, but sudden cardiac death. That's something we're learning more and more about as we've had better imaging techniques and genetic testing. We are now in a better position to try to identify those things that put people at risk for early heart attacks and sudden cardiac death.
Maggie McKay: What's the role of what you eat? Like unsaturated fats versus obesity, for example.
Dr. Michael Sills: And we'll talk about this next time, but there's a lot that we're learning about diet and weight. It turns out that the Mediterranean lifestyle, and it's not a diet, it's a lifestyle, seems to reduce the risk of cardiac events. We talk about something called MACE, which is an acronym for Major Adverse Cardiac Event. And we know that people who have certain kinds of lifestyles and diets are at much lower risk for major adverse cardiac events.
One of the things we're also learning is that obesity's not good for you. We kind of know that, and we talk about it anecdotally, but there's been some really interesting studies looking at inflammation and obesity. We've known for years that people have heart attacks at a certain time of day. We don't really understand why. We also know that there have been measurements of people's blood tests that correlate to kind of general inflammation, whether it's an infection or arthritis that seem to predict who is going to have a heart attack.
What we've never been able to do is tie the two together. Why is it that inflammation markers seem to predict the risk of heart attack? And one of the things that we have learned is that obesity actually increases your inflammatory state and that these markers can be affected by weight. Also, obesity, for example, can influence the development of congestive heart failure and a number of other things. So, we're learning that obesity along potentially with sedentary lifestyle can be a very large contributor to the risk of coronary artery disease.
Maggie McKay: And what defines obesity?
Dr. Michael Sills: Well, from the National Institute of Health, it is an abnormal, excessive fat accumulation that presents a risk to health. So, it's intentionally vague. You'll see people talk about BMIs greater than 25, that really is not a great way to look at obesity because it depends on your age, depends on height, it depends on a lot of things. But basically, when you're starting to see the effects of too much fat on your health is when people need to start thinking themselves as obese.
Also, there's other definitions including chronic, relapsing, multifactorial neurobehavioral disease, getting really technical, where an increase in body fat basically causes the fatty tissue, adipose tissue, to result in adverse metabolic; diabetes, for example, high blood pressure; biochemical and psychosocial health consequences. Certainly, people who are overweight tend to be more likely to be depressed. Chicken and egg, we don't know if they eat because they're depressed or not having a good body image contributes to that. But clearly, there are more than just a few effects that obesity has on people that's deleterious.
Maggie McKay: Dr. Sills, why is inflammation now considered a cardiac risk?
Dr. Michael Sills: So, a number of years ago, there was a study in Boston looking at 5,000 nurses. And they measured a lab test called CRP, which is again a very generic measurement of inflammation. They founded that the nurses who had higher levels of CRP were more likely to have heart attacks. So, it is now thought that inflammation, especially using something like CRP, may be as much a risk factor for the development of major cardiac events as poorly controlled high blood pressure or elevated cholesterol. So clearly, we're learning a lot more about why people have bad outcomes from coronary artery disease, and a big part of what precipitates some of these major events like heart attacks or strokes probably has to do with inflammation.
Maggie McKay: And what about the outside-to-in model?
Dr. Michael Sills: So, one of the things we've known for a long time is that there's different kinds of plaque in your heart. There are what are called stable plaques, which tend to be obstructive. In other words, they limit blood flow. Now, the same can occur in the carotid arteries or leg arteries, but they're basically heavily calcified and very stable. They may limit blood flow. They may cause chest pain. They may cause pain in legs when people walk, but they don't cause heart attacks.
What we've learned is that they're called soft plaques or vulnerable plaques that tend not to be obstructive, maybe 30%, 40% or less. These are the plaques that tend to rupture. And when they do, if they rupture in a carotid artery, go into your brain, you could have a TIA or stroke. Or if they rupture in your heart, they'll cause a heart attack. And again, one of the interesting questions is, why does that happen? Why do they rupture? And one of the things that we're learning is from coronary calcium scores, and the amount of fat that surrounds arteries, that the higher the calcium score, the higher the amount of fat surrounding arteries, the greater the risk of these soft plaques rupturing. So, we're learning that fat around your arteries seems also to contribute to the risk of having a major cardiac event.
Maggie McKay: Wow. We have a lot of work to do to get healthy and stay healthy. But like you said, it's all about prevention. What about patients with something called CAD and what is that and how do they factor in when it comes to inflammation?
Dr. Michael Sills: Well, coronary disease is basically any kind of plaque that occurs in the arteries that supply the heart. Like I was saying, we divide it into obstructive and non-obstructive, the plaques that limit blood flow and the plaques that don't. One of the things, like I said, that we've learned is it's the non-obstructive plaques that cause heart attacks. The bigger problem we have, just like trying to figure out how much fat there is around arteries, is we don't have any great imaging right now to determine how vulnerable a plaque is. You know, we can't really see 30% or 40% plaques. So, the problem is not that we can't image these, we don't even know which ones are at risk, so we can't go in and just put stents in every artery in the heart. That's why we fall back to the same question. We can try to identify people who are at increased risk, but then we're trying to use some of these new techniques to try and identify the people who are at the highest risks and see how aggressive we can get with our interventions to try not only to reduce the amount of plaque they have, but hopefully reduce the risk they have of having a heart attack or stroke, which is the sorts of things that will forshorten lives.
Maggie McKay: When it comes to plaque imaging, do you think in the future maybe they'll have better technology to take care of that to be able to see better?
Dr. Michael Sills: I think so. We are getting much better with CT scanning. For example, we can do a CT angiogram, which is the same kind of test that we do that is invasive, but with a CT scanner. And we're now getting better resolution. In other words, we can see smaller things, we can see them with faster scans. And our computer reconstructions allow us to get really good 3D images, which can help demonstrate some of the plaques that are vulnerable. Again, it comes back to a similar question, "Okay. So, you've identified a vulnerable plaque, you've identified somebody who's got inflammation, what are you going to do differently?" And that's still a question, but there's no question our ability to image is steadily improving with less radiation and less cost.
Maggie McKay: Well, that's good news. Less radiation, right? What about GLP-1s?
Dr. Michael Sills: That's been very interesting. It started with a category of drugs that were meant to treat diabetes. Along the way, we noticed that people were losing considerable amounts of weight, and a number of them have gotten quite popular. The one that gained the most popular is one called Ozempic, that people lost modest amounts of weight.
The newest one, tirzepatide, in one study that was published in New England Journal not so long ago, people were losing within six months of over 50 pounds. So, it is now possible to safely use a medicine for weight loss. Now, the drug is not approved for that. But certainly for somebody who's got pre-diabetes or borderline blood sugar, drugs like these are pretty remarkable. They have helped people lose a lot of weight.
One of the amazing things that we've seen with bariatric surgery, which many of us, me included, always believe you don't have to have any surgery you don't have to have. But one of the things that we've seen is when people lose large amounts of weight, their diabetes goes away. That's something we never thought would happen. Blood pressure normalizes. Cholesterol normalizes. And when you use some of these medications, their overall health improves. They live longer, they feel better.
So, these drugs may be that magic bullet that my patients always come in and ask for, "Doc, I got to lose weight. Nothing works. Do you have some pill that'll fix it?" The answer is no. We don't have a pill. We have a shot and it's expensive. But you have to look at the relative cost of taking care of somebody's diabetes and its complications, high blood pressure and its complications offset with the cost of these medications. So, I think there's a lot coming about how we manage weight going forward, whether it's some of the apps which are very helpful or pharmacologically. I think it's going to really change cardiologists' approach to prevention.
Maggie McKay: And what about lab tests?
Dr. Michael Sills: So, there's been obviously some testing to try and come up with inflammatory markers. We're still kind of early. There's a couple that are again very generalized reflections of inflammation. But in the absence of a chronic infection or a cancer, if someone has a lot of risk factors for coronary disease and has elevated inflammation, that is a clue to us that we need to be much more aggressive about risk factor modification.
We've known from a study called the Framingham Heart Study, which dates back to the '60s that anybody with a total cholesterol over 200 is at outsized risk for the development of major cardiac events. We learned later that cholesterol comes in different sizes, high-density particles, low-density particles, and all sorts in between. We've learned that low-density particles, LDLs, are much more likely to cause an increased risk of any kind of vascular effect. Of course, it's never that simple in the human body. We now know that there are proteins that sit on these LDLs that actually serve as hooks for the white blood cells to grab them out of your bloodstream and drag them into the arteries. There's one of these proteins called LPA, which also interestingly enough seems to increase the risk of vascular problems. So, we continue to learn about ways that we can pharmacologically modify people's risks. There are a new category of drugs, which lower LDL even more than we've been able to before, and they specifically target LPA, whereas statins don't. So, that's been a very exciting development that, as we continue to be able to test for both more sensitive metrics for inflammation as well as some of the more subtle aspects of elevated cholesterol, it's helping us target patients who are at the highest risk and what we can do for them.
Maggie McKay: Dr. Sills, how do you treat high cholesterol?
Dr. Michael Sills: There's been a lot of discussion over the years about dietary versus medical therapy. Dr. Ornish, who's been around for quite a long time, he's originally from Dallas and is now in California, has proposed a very aggressive diet. He was among the first people to suggest a plant-based diet and published an article that suggested that, with his plant-based diet, you could lower your cholesterol upwards of 10% to 20%.
Maggie McKay: Wow.
Dr. Michael Sills: The problem with that is there's been difficulty in proving that by dropping your cholesterol with diet, that you achieve the same benefits that you do with medical therapy. So, it's a whole 'nother discussion.
I think there's a lot of value to eating a healthy diet. And I think for many of us, more of a plant-based diet has a lot of benefits. But for people who have an elevated cholesterol especially associated with other risk factors like we mentioned, high blood pressure, diabetes, family history, smoking, these are people who a diet's probably not going to be enough.
While we absolutely encourage people to eat healthy and there's a lot of benefits to that, the statin drugs have roughly 30% to 40% risk reduction in both LDL and heart attack and stroke. So, I think everybody should eat a healthy as much as possible plant-based diet because it's good for reduction of cancer risk and lots of other good things. But if people have an elevated cholesterol associated with the risk factors, they will probably be best served with a medication.
Maggie McKay: So, vitamins or supplements also, or just the medication?
Dr. Michael Sills: There was a recent really good study in our banner journal of the Journal of the American College of Cardiology that looked at all the different supplements from garlic to cinnamon to red yeast rice, everything, and they compared it to statins, and the answer is none of them work. So, there is no vitamin, there is no supplement that effectively lowers your cholesterol, but people continue to want to find a non-pharmacologic alternative. But the irony is that anything that you put in your mouth that's in a pill form is a chemical. Whether it's a chemical that's produced by a major drug company that's been certified by the FDA or something that you buy at the grocery store that nobody really looks at, is what people want to do. But my attitude is if I'm going to put a chemical in my body, I want to know for sure that it's safe, and I want to know for sure that it works. So, no, I'm not a big fan of vitamins or supplements.
Maggie McKay: I'm so happy to hear that because my husband and I have this constant conversation. He takes a lot of vitamins and supplements and I'm like, "Okay, God, I love you," but I don't, and we're both very healthy. But, you know, it's interesting how people either are all in or not at all. Nevertheless, when it comes to numbers for cholesterol, how low do you want to go to be healthy?
Dr. Michael Sills: That's a really good question and I wish I had a simple, straightforward here's-the-answer. When the Framingham study came out in the '60s, they noticed a sharp drop off in the risk of cardiovascular events when the total cholesterol was under 200. When we were able to fractionate, divide the cholesterol up into LDL and HDL, we noted that there was a dropoff in events when the LDL was under 130.
In the early statin trials, the first one was called 4S and some subsequent studies, it seemed that as the LDL dropped under 120 and then under 100, that the risk continued to decline. There have been questions, however, because amazingly two really good big studies came up with diametrically opposite answers, that one said that if the LDL continues to drop to 50, under 70, there was a better outcome. And another that said, once you hit 70, there's no additional risk reduction.
So, we've been kind of stuck not knowing do you really want to try and take it lower than 70? Well, the problem has been that we have not had any medications that can do that. Even with the largest doses of statins and everything else we can throw at people, up until very recently, it's been impossible to get the LDL under 70. You just can't give people enough medicines. There is a new category of drugs, PCSK9 is what they're called, and they're developed here in the same lab at UT Southwestern by Brown and Goldstein, who developed the very first statins. They have come up with this new category of drugs, which can actually lower LDL even lower than 70.
What we don't know yet, because these drugs are relatively new, is whether that's going to have an outcome benefit. There's a number of people who think that the LDL should be as low as possible, and that may well be true. But right now, we don't know. There's a big study going on right now with the newest of these drugs, which is they're all injectable, but the newest of these drugs actually only needs to be given once a year.
Maggie McKay: Wow, there's the benefit.
Dr. Michael Sills: Well, the classic pattern is you get a call from the mail-in pharmacy that says, "Just so you know, your patient took their statin for three months, probably felt fine, stopped it. But started it again about a month before they came in to get their blood drawn because they wanted it to look good."
Maggie McKay: Oh, my gosh.
Dr. Michael Sills: And that's very surprisingly typical. So with a once a year shot, I think we're going to be in a much better position to really answer the question, "Should the LDL be 50 or less?" Like I said, there are people who think it ought to be, but we're probably two to five years away from knowing that. But in the meantime, these drugs are a huge addition to our armamentarium about how to prevent coronary artery disease and strokes.
Maggie McKay: And what about calcium scores or stress testing?
Dr. Michael Sills: Calcium scores have had a bit of a checkered past because they were, like not unfortunately a number of tests, put out there as a measure of your risk for coronary disease, but without a lot of large outcome studies. So, people were getting these calcium scores and we really didn't know what to make of it. We knew at some level that the higher the calcium score, the greater the risk of developing coronary disease. Now, we've learned that the calcium scores don't necessarily mean you have any obstructive coronary disease; in other words, plaques large enough on the inside to cause chest pain, for example. But some of these big studies have shown that it reflects the total amount of plaque you have in your coronary arteries.
So, a really great study that was done in the Netherlands looked at almost 30,000 people and they compared calcium score with a CT angiogram; in other words, really looking at the blockages people had; dividing it up into no blockage, one artery, two artery, or all three arteries blocked versus a calcium score. And what was really interesting was the calcium score was much more predictive of major cardiac events. So, what do you do with it?
The problem is we're back to the same thing. We can't really identify which plaques are about to cause a heart attack. But what many of us are now doing is we're using the calcium score in two ways. One is if the calcium score is elevated, well, that pushes us more to think about these PCSK9 drugs. They're expensive, they're not for everybody. But for certainly people who have a very elevated calcium score, we need to be as aggressive with these people as we can with diabetes management, high blood pressure management and cholesterol management. So, I think that's very, very useful to know how aggressive we need to be.
Then, there's also those lucky people who have a calcium score of zero, and there's been another recent study that looked at the calcium score of zero. And basically, if your score is zero, you will never have a heart attack. There's some debate as to whether or not you even need to treat their cholesterol. I do. But it can be very useful if you're trying to argue with some young person who's got an elevated cholesterol and says, "I don't want to take anything for it. Do I really have to?" And my deal with them is if your calcium score is zero, then no. But they can be very helpful to try and predict the risk and how aggressive you should be with risk factor modification.
Maggie McKay: Do you see a lot of young people with high cholesterol?
Dr. Michael Sills: Yes. One of the problems has been up until maybe the last 10 years with pediatricians were not really tuned in to a lot of preventive cardiac management. What has also changed, and I of course point fingers at sedentary lifestyles, video games, things like that, but we're seeing young kids who are really overweight. We're seeing the development of type 2 diabetes in young people, which we never saw before, and elevated blood pressure.
So, we're now seeing people develop significant problems and cardiac risk factors in their teens, which we never saw before. And all of a sudden now, the pediatricians are getting tuned into cardiac risk factor management. Whereas they never really needed to check cholesterol before, all of a sudden now we're seeing elevated cholesterol in adolescents. And there's some really good data suggesting that if you start treating them at an early age, that you have a greater likelihood to preventing long-term cardiac risks. It's just we have to get people tuned into thinking about adolescence as having significant cardiac risk factors. But all you have to do is look at how large we are. I mean, there's the prediction at the rate of obesity in this country, especially in this part of the country, is significant and it's growing. People are getting bigger all the time.
Maggie McKay: Right. So sad. In closing, Dr. Sills, is there one takeaway that you would like people listening to remember from this conversation?
Dr. Michael Sills: Yeah. The most important thing that cardiologists can do at this point is not just treat the manifestations of vascular disease, but to really think and work with patients. I mean, we need to be partners in all of this. My job is to help people understand what the risk factors are, what increases their risk factor for vascular disease, and what we can do together to try and reduce those risk factors, whether it's exercise, lifestyle modifications, diet, pharmacologic interventions. I think that to me is the best part of what I do, is helping people understand what their risk factors are and how they can modify them.
Maggie McKay: Dr. Sills, it's been a pleasure and we so appreciate you sharing your expertise with us. This has been very informative. And it's just the first episode of a three-part series on cardiovascular health, so we look forward to hearing from you on the next two, which will be available soon. In part two, we're going to talk about how to approach heart-healthy eating, understanding that healthy eating is not a diet but a lifestyle. And part three is going to focus on healthy lifestyles including exercise and sleep, so underrated.
Dr. Michael Sills: Well, thank you very much for having me.
Maggie McKay: Absolutely. We've been talking with Dr. Michael Sills, cardiologist on the medical staff of Baylor Scott & White Heart and Vascular Hospital Dallas. Thanks for checking out this episode of HeartSpeak. If you'd like to find a cardiologist on the medical staff, please call 1-844-279-3627 or visit bswhealth.com/heartdfw.
Thanks for listening to HeartSpeak, the podcast from Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth. If you found this podcast helpful, please share it on your social channels. And to learn more, please check out additional HeartSpeak podcasts on specific cardiovascular topics. I'm Maggie McKay. Thanks for listening.
Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth, joint ownership with physicians.
New Trends in Preventive Heart Health with Dr. Michael Sills
Maggie McKay: Unless your heart races or you experience shallow breathing, you probably don't think much about your heart just from day to day. But when you do have symptoms, you want to know what's going on and how to prevent that from ever happening.
Joining me today to talk about heart health is Dr. Michael Sills, cardiologist on the medical staff of Baylor Scott & White Heart and Vascular Hospital-Dallas, to talk about the new trends in preventive heart health and more.
This is HeartSpeak, the podcast from Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth. I'm Maggie McKay. Welcome, Dr. Sills. What an honor to have you here. Thanks for making the time. Could you please introduce yourself?
Dr. Michael Sills: First of all, thank you for having me. I'm Michael Sills. I'm a cardiologist. I've been here my entire career and one of my big interests is trying to prevent cardiac issues, kind of prevent coronary artery disease. We see all too much of the aftermath, but it's only been recently we focused more on what we could do to prevent people from getting sick.
Maggie McKay: Well, we are just so grateful to have you here for this first episode of a three-part series of podcasts on cardiovascular health. So today, we're going to concentrate on some of the basics. And the other two, we'll dive deeper into healthy eating and adding exercise into your lifestyle for heart health. And speaking of diving in, let's just start with what are the cardiac risk factors that people need to know about?
Dr. Michael Sills: Traditionally, we talk about five different things. One is high blood pressure. Two is high cholesterol. Three is diabetes. Four is smoking. And five, the one thing we can't do much about, is familial risk of coronary artery disease.
Maggie McKay: That's the scariest, right? Because like you said, you could do all those other things and who knows, if like for instance, both your parents had heart attacks, are you at how much of a higher risk?
Dr. Michael Sills: A lot of that depends on what the other risk factors are. Certainly, there are certain inheritable conditions that predispose you not only for heart attacks, but sudden cardiac death. That's something we're learning more and more about as we've had better imaging techniques and genetic testing. We are now in a better position to try to identify those things that put people at risk for early heart attacks and sudden cardiac death.
Maggie McKay: What's the role of what you eat? Like unsaturated fats versus obesity, for example.
Dr. Michael Sills: And we'll talk about this next time, but there's a lot that we're learning about diet and weight. It turns out that the Mediterranean lifestyle, and it's not a diet, it's a lifestyle, seems to reduce the risk of cardiac events. We talk about something called MACE, which is an acronym for Major Adverse Cardiac Event. And we know that people who have certain kinds of lifestyles and diets are at much lower risk for major adverse cardiac events.
One of the things we're also learning is that obesity's not good for you. We kind of know that, and we talk about it anecdotally, but there's been some really interesting studies looking at inflammation and obesity. We've known for years that people have heart attacks at a certain time of day. We don't really understand why. We also know that there have been measurements of people's blood tests that correlate to kind of general inflammation, whether it's an infection or arthritis that seem to predict who is going to have a heart attack.
What we've never been able to do is tie the two together. Why is it that inflammation markers seem to predict the risk of heart attack? And one of the things that we have learned is that obesity actually increases your inflammatory state and that these markers can be affected by weight. Also, obesity, for example, can influence the development of congestive heart failure and a number of other things. So, we're learning that obesity along potentially with sedentary lifestyle can be a very large contributor to the risk of coronary artery disease.
Maggie McKay: And what defines obesity?
Dr. Michael Sills: Well, from the National Institute of Health, it is an abnormal, excessive fat accumulation that presents a risk to health. So, it's intentionally vague. You'll see people talk about BMIs greater than 25, that really is not a great way to look at obesity because it depends on your age, depends on height, it depends on a lot of things. But basically, when you're starting to see the effects of too much fat on your health is when people need to start thinking themselves as obese.
Also, there's other definitions including chronic, relapsing, multifactorial neurobehavioral disease, getting really technical, where an increase in body fat basically causes the fatty tissue, adipose tissue, to result in adverse metabolic; diabetes, for example, high blood pressure; biochemical and psychosocial health consequences. Certainly, people who are overweight tend to be more likely to be depressed. Chicken and egg, we don't know if they eat because they're depressed or not having a good body image contributes to that. But clearly, there are more than just a few effects that obesity has on people that's deleterious.
Maggie McKay: Dr. Sills, why is inflammation now considered a cardiac risk?
Dr. Michael Sills: So, a number of years ago, there was a study in Boston looking at 5,000 nurses. And they measured a lab test called CRP, which is again a very generic measurement of inflammation. They founded that the nurses who had higher levels of CRP were more likely to have heart attacks. So, it is now thought that inflammation, especially using something like CRP, may be as much a risk factor for the development of major cardiac events as poorly controlled high blood pressure or elevated cholesterol. So clearly, we're learning a lot more about why people have bad outcomes from coronary artery disease, and a big part of what precipitates some of these major events like heart attacks or strokes probably has to do with inflammation.
Maggie McKay: And what about the outside-to-in model?
Dr. Michael Sills: So, one of the things we've known for a long time is that there's different kinds of plaque in your heart. There are what are called stable plaques, which tend to be obstructive. In other words, they limit blood flow. Now, the same can occur in the carotid arteries or leg arteries, but they're basically heavily calcified and very stable. They may limit blood flow. They may cause chest pain. They may cause pain in legs when people walk, but they don't cause heart attacks.
What we've learned is that they're called soft plaques or vulnerable plaques that tend not to be obstructive, maybe 30%, 40% or less. These are the plaques that tend to rupture. And when they do, if they rupture in a carotid artery, go into your brain, you could have a TIA or stroke. Or if they rupture in your heart, they'll cause a heart attack. And again, one of the interesting questions is, why does that happen? Why do they rupture? And one of the things that we're learning is from coronary calcium scores, and the amount of fat that surrounds arteries, that the higher the calcium score, the higher the amount of fat surrounding arteries, the greater the risk of these soft plaques rupturing. So, we're learning that fat around your arteries seems also to contribute to the risk of having a major cardiac event.
Maggie McKay: Wow. We have a lot of work to do to get healthy and stay healthy. But like you said, it's all about prevention. What about patients with something called CAD and what is that and how do they factor in when it comes to inflammation?
Dr. Michael Sills: Well, coronary disease is basically any kind of plaque that occurs in the arteries that supply the heart. Like I was saying, we divide it into obstructive and non-obstructive, the plaques that limit blood flow and the plaques that don't. One of the things, like I said, that we've learned is it's the non-obstructive plaques that cause heart attacks. The bigger problem we have, just like trying to figure out how much fat there is around arteries, is we don't have any great imaging right now to determine how vulnerable a plaque is. You know, we can't really see 30% or 40% plaques. So, the problem is not that we can't image these, we don't even know which ones are at risk, so we can't go in and just put stents in every artery in the heart. That's why we fall back to the same question. We can try to identify people who are at increased risk, but then we're trying to use some of these new techniques to try and identify the people who are at the highest risks and see how aggressive we can get with our interventions to try not only to reduce the amount of plaque they have, but hopefully reduce the risk they have of having a heart attack or stroke, which is the sorts of things that will forshorten lives.
Maggie McKay: When it comes to plaque imaging, do you think in the future maybe they'll have better technology to take care of that to be able to see better?
Dr. Michael Sills: I think so. We are getting much better with CT scanning. For example, we can do a CT angiogram, which is the same kind of test that we do that is invasive, but with a CT scanner. And we're now getting better resolution. In other words, we can see smaller things, we can see them with faster scans. And our computer reconstructions allow us to get really good 3D images, which can help demonstrate some of the plaques that are vulnerable. Again, it comes back to a similar question, "Okay. So, you've identified a vulnerable plaque, you've identified somebody who's got inflammation, what are you going to do differently?" And that's still a question, but there's no question our ability to image is steadily improving with less radiation and less cost.
Maggie McKay: Well, that's good news. Less radiation, right? What about GLP-1s?
Dr. Michael Sills: That's been very interesting. It started with a category of drugs that were meant to treat diabetes. Along the way, we noticed that people were losing considerable amounts of weight, and a number of them have gotten quite popular. The one that gained the most popular is one called Ozempic, that people lost modest amounts of weight.
The newest one, tirzepatide, in one study that was published in New England Journal not so long ago, people were losing within six months of over 50 pounds. So, it is now possible to safely use a medicine for weight loss. Now, the drug is not approved for that. But certainly for somebody who's got pre-diabetes or borderline blood sugar, drugs like these are pretty remarkable. They have helped people lose a lot of weight.
One of the amazing things that we've seen with bariatric surgery, which many of us, me included, always believe you don't have to have any surgery you don't have to have. But one of the things that we've seen is when people lose large amounts of weight, their diabetes goes away. That's something we never thought would happen. Blood pressure normalizes. Cholesterol normalizes. And when you use some of these medications, their overall health improves. They live longer, they feel better.
So, these drugs may be that magic bullet that my patients always come in and ask for, "Doc, I got to lose weight. Nothing works. Do you have some pill that'll fix it?" The answer is no. We don't have a pill. We have a shot and it's expensive. But you have to look at the relative cost of taking care of somebody's diabetes and its complications, high blood pressure and its complications offset with the cost of these medications. So, I think there's a lot coming about how we manage weight going forward, whether it's some of the apps which are very helpful or pharmacologically. I think it's going to really change cardiologists' approach to prevention.
Maggie McKay: And what about lab tests?
Dr. Michael Sills: So, there's been obviously some testing to try and come up with inflammatory markers. We're still kind of early. There's a couple that are again very generalized reflections of inflammation. But in the absence of a chronic infection or a cancer, if someone has a lot of risk factors for coronary disease and has elevated inflammation, that is a clue to us that we need to be much more aggressive about risk factor modification.
We've known from a study called the Framingham Heart Study, which dates back to the '60s that anybody with a total cholesterol over 200 is at outsized risk for the development of major cardiac events. We learned later that cholesterol comes in different sizes, high-density particles, low-density particles, and all sorts in between. We've learned that low-density particles, LDLs, are much more likely to cause an increased risk of any kind of vascular effect. Of course, it's never that simple in the human body. We now know that there are proteins that sit on these LDLs that actually serve as hooks for the white blood cells to grab them out of your bloodstream and drag them into the arteries. There's one of these proteins called LPA, which also interestingly enough seems to increase the risk of vascular problems. So, we continue to learn about ways that we can pharmacologically modify people's risks. There are a new category of drugs, which lower LDL even more than we've been able to before, and they specifically target LPA, whereas statins don't. So, that's been a very exciting development that, as we continue to be able to test for both more sensitive metrics for inflammation as well as some of the more subtle aspects of elevated cholesterol, it's helping us target patients who are at the highest risk and what we can do for them.
Maggie McKay: Dr. Sills, how do you treat high cholesterol?
Dr. Michael Sills: There's been a lot of discussion over the years about dietary versus medical therapy. Dr. Ornish, who's been around for quite a long time, he's originally from Dallas and is now in California, has proposed a very aggressive diet. He was among the first people to suggest a plant-based diet and published an article that suggested that, with his plant-based diet, you could lower your cholesterol upwards of 10% to 20%.
Maggie McKay: Wow.
Dr. Michael Sills: The problem with that is there's been difficulty in proving that by dropping your cholesterol with diet, that you achieve the same benefits that you do with medical therapy. So, it's a whole 'nother discussion.
I think there's a lot of value to eating a healthy diet. And I think for many of us, more of a plant-based diet has a lot of benefits. But for people who have an elevated cholesterol especially associated with other risk factors like we mentioned, high blood pressure, diabetes, family history, smoking, these are people who a diet's probably not going to be enough.
While we absolutely encourage people to eat healthy and there's a lot of benefits to that, the statin drugs have roughly 30% to 40% risk reduction in both LDL and heart attack and stroke. So, I think everybody should eat a healthy as much as possible plant-based diet because it's good for reduction of cancer risk and lots of other good things. But if people have an elevated cholesterol associated with the risk factors, they will probably be best served with a medication.
Maggie McKay: So, vitamins or supplements also, or just the medication?
Dr. Michael Sills: There was a recent really good study in our banner journal of the Journal of the American College of Cardiology that looked at all the different supplements from garlic to cinnamon to red yeast rice, everything, and they compared it to statins, and the answer is none of them work. So, there is no vitamin, there is no supplement that effectively lowers your cholesterol, but people continue to want to find a non-pharmacologic alternative. But the irony is that anything that you put in your mouth that's in a pill form is a chemical. Whether it's a chemical that's produced by a major drug company that's been certified by the FDA or something that you buy at the grocery store that nobody really looks at, is what people want to do. But my attitude is if I'm going to put a chemical in my body, I want to know for sure that it's safe, and I want to know for sure that it works. So, no, I'm not a big fan of vitamins or supplements.
Maggie McKay: I'm so happy to hear that because my husband and I have this constant conversation. He takes a lot of vitamins and supplements and I'm like, "Okay, God, I love you," but I don't, and we're both very healthy. But, you know, it's interesting how people either are all in or not at all. Nevertheless, when it comes to numbers for cholesterol, how low do you want to go to be healthy?
Dr. Michael Sills: That's a really good question and I wish I had a simple, straightforward here's-the-answer. When the Framingham study came out in the '60s, they noticed a sharp drop off in the risk of cardiovascular events when the total cholesterol was under 200. When we were able to fractionate, divide the cholesterol up into LDL and HDL, we noted that there was a dropoff in events when the LDL was under 130.
In the early statin trials, the first one was called 4S and some subsequent studies, it seemed that as the LDL dropped under 120 and then under 100, that the risk continued to decline. There have been questions, however, because amazingly two really good big studies came up with diametrically opposite answers, that one said that if the LDL continues to drop to 50, under 70, there was a better outcome. And another that said, once you hit 70, there's no additional risk reduction.
So, we've been kind of stuck not knowing do you really want to try and take it lower than 70? Well, the problem has been that we have not had any medications that can do that. Even with the largest doses of statins and everything else we can throw at people, up until very recently, it's been impossible to get the LDL under 70. You just can't give people enough medicines. There is a new category of drugs, PCSK9 is what they're called, and they're developed here in the same lab at UT Southwestern by Brown and Goldstein, who developed the very first statins. They have come up with this new category of drugs, which can actually lower LDL even lower than 70.
What we don't know yet, because these drugs are relatively new, is whether that's going to have an outcome benefit. There's a number of people who think that the LDL should be as low as possible, and that may well be true. But right now, we don't know. There's a big study going on right now with the newest of these drugs, which is they're all injectable, but the newest of these drugs actually only needs to be given once a year.
Maggie McKay: Wow, there's the benefit.
Dr. Michael Sills: Well, the classic pattern is you get a call from the mail-in pharmacy that says, "Just so you know, your patient took their statin for three months, probably felt fine, stopped it. But started it again about a month before they came in to get their blood drawn because they wanted it to look good."
Maggie McKay: Oh, my gosh.
Dr. Michael Sills: And that's very surprisingly typical. So with a once a year shot, I think we're going to be in a much better position to really answer the question, "Should the LDL be 50 or less?" Like I said, there are people who think it ought to be, but we're probably two to five years away from knowing that. But in the meantime, these drugs are a huge addition to our armamentarium about how to prevent coronary artery disease and strokes.
Maggie McKay: And what about calcium scores or stress testing?
Dr. Michael Sills: Calcium scores have had a bit of a checkered past because they were, like not unfortunately a number of tests, put out there as a measure of your risk for coronary disease, but without a lot of large outcome studies. So, people were getting these calcium scores and we really didn't know what to make of it. We knew at some level that the higher the calcium score, the greater the risk of developing coronary disease. Now, we've learned that the calcium scores don't necessarily mean you have any obstructive coronary disease; in other words, plaques large enough on the inside to cause chest pain, for example. But some of these big studies have shown that it reflects the total amount of plaque you have in your coronary arteries.
So, a really great study that was done in the Netherlands looked at almost 30,000 people and they compared calcium score with a CT angiogram; in other words, really looking at the blockages people had; dividing it up into no blockage, one artery, two artery, or all three arteries blocked versus a calcium score. And what was really interesting was the calcium score was much more predictive of major cardiac events. So, what do you do with it?
The problem is we're back to the same thing. We can't really identify which plaques are about to cause a heart attack. But what many of us are now doing is we're using the calcium score in two ways. One is if the calcium score is elevated, well, that pushes us more to think about these PCSK9 drugs. They're expensive, they're not for everybody. But for certainly people who have a very elevated calcium score, we need to be as aggressive with these people as we can with diabetes management, high blood pressure management and cholesterol management. So, I think that's very, very useful to know how aggressive we need to be.
Then, there's also those lucky people who have a calcium score of zero, and there's been another recent study that looked at the calcium score of zero. And basically, if your score is zero, you will never have a heart attack. There's some debate as to whether or not you even need to treat their cholesterol. I do. But it can be very useful if you're trying to argue with some young person who's got an elevated cholesterol and says, "I don't want to take anything for it. Do I really have to?" And my deal with them is if your calcium score is zero, then no. But they can be very helpful to try and predict the risk and how aggressive you should be with risk factor modification.
Maggie McKay: Do you see a lot of young people with high cholesterol?
Dr. Michael Sills: Yes. One of the problems has been up until maybe the last 10 years with pediatricians were not really tuned in to a lot of preventive cardiac management. What has also changed, and I of course point fingers at sedentary lifestyles, video games, things like that, but we're seeing young kids who are really overweight. We're seeing the development of type 2 diabetes in young people, which we never saw before, and elevated blood pressure.
So, we're now seeing people develop significant problems and cardiac risk factors in their teens, which we never saw before. And all of a sudden now, the pediatricians are getting tuned into cardiac risk factor management. Whereas they never really needed to check cholesterol before, all of a sudden now we're seeing elevated cholesterol in adolescents. And there's some really good data suggesting that if you start treating them at an early age, that you have a greater likelihood to preventing long-term cardiac risks. It's just we have to get people tuned into thinking about adolescence as having significant cardiac risk factors. But all you have to do is look at how large we are. I mean, there's the prediction at the rate of obesity in this country, especially in this part of the country, is significant and it's growing. People are getting bigger all the time.
Maggie McKay: Right. So sad. In closing, Dr. Sills, is there one takeaway that you would like people listening to remember from this conversation?
Dr. Michael Sills: Yeah. The most important thing that cardiologists can do at this point is not just treat the manifestations of vascular disease, but to really think and work with patients. I mean, we need to be partners in all of this. My job is to help people understand what the risk factors are, what increases their risk factor for vascular disease, and what we can do together to try and reduce those risk factors, whether it's exercise, lifestyle modifications, diet, pharmacologic interventions. I think that to me is the best part of what I do, is helping people understand what their risk factors are and how they can modify them.
Maggie McKay: Dr. Sills, it's been a pleasure and we so appreciate you sharing your expertise with us. This has been very informative. And it's just the first episode of a three-part series on cardiovascular health, so we look forward to hearing from you on the next two, which will be available soon. In part two, we're going to talk about how to approach heart-healthy eating, understanding that healthy eating is not a diet but a lifestyle. And part three is going to focus on healthy lifestyles including exercise and sleep, so underrated.
Dr. Michael Sills: Well, thank you very much for having me.
Maggie McKay: Absolutely. We've been talking with Dr. Michael Sills, cardiologist on the medical staff of Baylor Scott & White Heart and Vascular Hospital Dallas. Thanks for checking out this episode of HeartSpeak. If you'd like to find a cardiologist on the medical staff, please call 1-844-279-3627 or visit bswhealth.com/heartdfw.
Thanks for listening to HeartSpeak, the podcast from Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth. If you found this podcast helpful, please share it on your social channels. And to learn more, please check out additional HeartSpeak podcasts on specific cardiovascular topics. I'm Maggie McKay. Thanks for listening.
Baylor Scott & White Heart and Vascular Hospital, Dallas and Fort Worth, joint ownership with physicians.