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Bob Underwood, MD (Host): Hypertension is often dubbed as the silent killer and it presents a significant burden on global health. Despite medical advances, barriers persist in achieving optimal blood pressure control, posing challenges for both patients and for health care providers alike. This is Expert Insights with the Carle Foundation Hospital and I'm your host, Dr. Bob Underwood. Carle Health Cardiologist, Dr. Surya

Host: Chaturvedula

Bob Underwood, MD (Host): is with us today to discuss advances in treating chronic hypertension. Join us as we uncover some of the complexities surrounding hypertension management and explore the implications of failing to reach blood pressure goals.

And while we're at it, we'll talk about some newer device-based strategies as well. Dr. Chaturvedula, it's good to have you here to join us to talk about hypertension management. You know, this is a seemingly ubiquitous medical condition. For we clinical people, it always seems to play a part in patient care. So thanks for joining us to talk about it today.

Surya Chaturvedula, MD: Pleasure being here.

Host: As a cardiologist with Carle Health, can you talk about the significant burden that hypertension places on your patient population? You know, what are the implications for their outcomes?

Surya Chaturvedula, MD: I think for starters, set aside cardiology, I don't think there's any healthcare professional that has a day in their life without taking care of a patient with hypertension, be it in the hospital or in the outpatient setting or in the community. As you've clearly stated, it's a silent killer, and the numbers when we talk about hypertension are just huge.

One in four adults in the world today suffers from hypertension that has been estimated as a whopping number of 1.6 billion, as of 2025 is something that is projected. And as you stated, it's not just hypertension, but the aftermath of hypertension, the end organ damage that it's related to, for an example, as you said, in my specialty, if I were to take ischemic heart disease, more than half of the patients who die from ischemic heart disease is because of hypertension.

Similarly, patients with stroke, be it ischemic stroke or a bleeding stroke, a hemorrhagic stroke, is pretty commonly because of hypertension. Not only that, myocardial infarction, atrial fibrillation, congestive heart failure, renal failure, so you name it and hypertension is always to blame.

Host: Yeah, absolutely. And I'm an emergency physician. And so, you know, we often deal with these folks, and these patients trying to care for them in extremis. So is absolutely ubiquitous in terms of the patients we see. So what are some of the biggest barriers that patients face in being able to achieve blood pressure goals?

Surya Chaturvedula, MD: Like with many other health advice we give to the patients, obviously compliance is the biggest thing in hypertension management. All of us know that the pillars for treatment of hypertension begin at lifestyle. Clearly a heart healthy diet, healthy lifestyle is the beginning.

So the non-compliance piece kind of starts from there. And then to add to the complexity of that and with the industrialization, with the busy lifestyles that our patients have sometimes, adverse socioeconomic factors that they're dealing with, also kind of add another layer of complexity to it.

But clearly, I feel biggest barrier in achieving our so called goals, which all of our societies have set in terms of achieving blood pressure goals, is compliance with medications. Through my training and stuff, you always learn about medications, their mechanisms, their efficacy, et cetera, but, recently in my journey of hypertension, I was quite taken aback by some of the science that exists here, they're part experiments. Just for example, there was this survey for hypertension patients and nearly 8 percent of patients were actually willing to trade as much as two years of their life rather than taking a medication. So that kind of tells you what the patients are, how the patients are looking at taking medications, keeping their blood pressure goal, and the implications of not being at goal.

Bob Underwood, MD (Host): Wow. So how do these barriers impact their health and wellbeing?

Surya Chaturvedula, MD: The barriers, I'll answer that in two pieces. I think the biggest challenge in this aspect is that the barriers exist in their daily life, but the implications of that might not be quite evident to them in the near future. As you preface, it's a silent killer.

So it's these barriers in their daily life that kind of pile up on them, leading to uncontrolled blood pressure, which ultimately translates to adverse outcomes in the long run.

Host: Yeah. I agree with one of the things you're saying is, and I don't know how many times I've asked the patient, well, I felt better, so I stopped taking the medication.

Surya Chaturvedula, MD: You will see this every day that there are so many patients who have very high blood pressures and they feel fine. So it doesn't have to be that they are feeling poorly. So that's the distinction of other acute health problems that we deal with a patient having a stroke or a heart attack. They're feeling poorly. So they see the need to seek an emergency attention. But when they're walking around with a very high blood pressure and not really feeling any symptoms, they might not go seek attention right away.

Host: In the intro, we said we were going to talk about some of the newer and device based, therapies. So can you explain some rationale behind device based therapies such as renal denervation or RDN for treating hypertension?

Surya Chaturvedula, MD: Sure. So when we take care of these patients with hypertension, as we said, the first layer is the modifications in their behavior. The second layer is medications. And as all of us who deal with these patients, the medications kind of target on various aspects which regulate blood pressure, so to speak.

So to answer renal denervation, the rationale, one needs to understand the interplay between various organ systems. And let's just focus on two of them, kidney and the brain, which ultimately are regulating it with the after effects of blood pressure being felt by several other organs. In renal denervation, we are trying to modulate the interaction between the signals that the kidneys are sending to the brain through the afferent and the efferent arterioles.

So we're trying to modulate that as a result of which we are hoping to achieve a blood pressure reduction. Now, I would like our audience to understand that on an average, a blood pressure pill is expected or hope that it can reduce the blood pressure by, uh, around 5 millimeters. So why do we worry so much about 5 millimeters?

Actually the FDA mandates that any kind of therapy that you are willing to test should be able to reduce the blood pressure by 5 because this magic number of 5 millimeter reduction in an office blood pressure translates to a much larger reduction in outcomes. Like a 5 millimeter reduction in blood pressure can actually lead to a 10 percent reduction in major adverse cardiovascular events, about 13 percent reduction in heart failure, about 5 percent reduction in CV death or cardiovascular death.

Host: So speaking of those kinds of outcomes, what are some of the promising results that you're seeing out in the studies as far as RDN is concerned?

Surya Chaturvedula, MD: So RDN has been actually in the news for so long because mechanistically it sounds very good but the early scientific trials did not really give a very positive outlook and that's multifactorial and probably at a later, different discussion altogether, but more recently with device iterations and also with a smarter planning of trial designs, we have seen now in the U.S. we have two modalities which are now FDA approved. One is a radio frequency based therapy. The other one is an ultrasound based therapy. But both of them are basically designed to do the same thing is to deal with the kidneys. And both of them have more or less a similar kind of effect.

So the trials, the randomized trials, have actually gone through a series, first trying to focus on patients who are on meds and then trying to focus on patients who are off meds, but if I have to give you like a summary, both of them have done what a single drug would do that is at an average blood pressure reduction of about five millimeters.

Host: Okay, and that was going to be my question. Are we hitting that target that you mentioned earlier?

Surya Chaturvedula, MD: That is correct. We are definitely hitting the target, but we have obviously not yet shown, we are improving the outcomes, which I would I think that would be something for the future, but like with any procedure or a device, first we have to establish that it is efficacious, which we have done.

It clearly demonstrates that it can reduce blood pressure by about five millimeters. It has to be safe, which both these devices, in their trials and also the large body of evidence that we now have for about 10 years, demonstrates that this procedure is incredibly safe because it's one thing that it's efficacious but what does it do to the kidneys?

What are the long term impacts? Is there any renal dysfunction? Any renal artery stenosis would be some valid concerns. There does not appear to be any such concern. So in these patients, when you actually follow them, the natural progression of a renal decline were to occur in a hypertension patient. It does not seem to alter that trajectory in whichever way. So, I think it's effective and safe is what are the two outcomes from these trials.

Host: Yeah, and that's really, really promising. How would you approach patient selection for RDN versus using medications or would it be a combination of both? I mean, what would be the patient selection criteria?

Surya Chaturvedula, MD: Sure. Let me, kind of answer this in a little bit, uh, complex way, as like with any other medical decision. It's not going to be, a straightforward decision. It is a shared decision. We always will addtwo medications. It's not going to be in the place of a medication. But one very important concept that we need to understand is, it's been seen that the nighttime blood pressures, like in the emergency room, when you've taken care of patients, worst things happen first thing in the morning.

Heart failure, strokes, MIs. The nighttime blood pressure is very closely related to long term outcomes. The beauty of a device therapy like this is that you have what's called an always on phenomena. So there is no on, off, like a drug, you know, there's no peak and then drop and then it's not relying on a compliance of the patient.

So I would approach this as an adjunct to the therapies that exist when we are unable to achieve the goal blood pressure. And I think we should also try and select patients in whom that would be the maximum bang for the buck. By that I mean patient who is more likely to have major cardiac and vascular and neurovascular outcomes if the blood pressure were not to be controlled.

A simple tool could be, let's say, a 10 year ASCVD risk score, which can sub select such patients. Obviously, you have to be eligible to do this procedure, meaning you could in the trials, patients with the GFR over 40 were selected. So your advanced renal failure patients would not be a candidate for it.

You need to have anatomy which is favorable for it. Patients with a prior renal artery stenosis, renal artery stent, fibromuscular dysplasia would not be candidates for it. Patients ought to have adequate access, where as things stand today, we do this procedure from the femoral artery, but I'm very positive that in the years to come, we'll migrate it to the radial artery.

So access ought to be deciding factor. The most important thing is it should not be a case of a secondary hypertension. So like with any other hypertension patient, you're excluding your endocrine causes as not being the cases for the uncontrolled blood pressure in whom this therapy has not been tested yet.

Host: Right. That makes total sense. And also what you're saying is, it would be an intervention that would have to happen before there's end organ damage around the kidneys. So,

Surya Chaturvedula, MD: Exactly right.

Host: So, anything else that you would like to add as we're kind of closing for today?

Surya Chaturvedula, MD: I think this is a very promising field. As we speak, actually, there is one other modality using alcohol ablation, but the idea is being the same. As a matter of fact, as a side note, this is something that is not new to medicine. Several decades ago, surgeons used to do sympathectomy, it's just that it was more, an open surgical procedure and very morbid procedure, so it's an amazing field that we went back to bench and re-imagined how this can be done, and we are here with iterations.

 Although I am very enthusiastic about this procedure in my own mind and also as a full disclosure to my patients, there are still a few unanswered questions. When you look at the scientific data, about one in four patients don't respond. So we don't really know who are those patients who would not respond.

So I think we got to be humble in that regard. And there's really no outcome data yet. Meaning, yes, I'm controlling the blood pressure, but by doing this procedure, am I affecting their long term outcome? Now, logic would tell me that, with reduction in blood pressure, how you get it down shouldn't really matter as long as you're getting it down.

I mean, a lot of things that we use in current practice, aldactone, hydralazine, minoxidil, clonidine, none of these have outcome data. Yet we use them every single day. So I wouldn't imagine that this would be much different than the rest and, cost effectiveness. I think we are talking about a public health issue. Hypertension is so prevalent. So cost effective data is also going to be a very important thing to look at.

Host: So would someone who responds to an ACE inhibitor be more likely to respond to this since you're really, wouldn't it be the same mechanism of an angiotensin converting enzyme because it's really responding around the renal artery pressures?

Surya Chaturvedula, MD: Would they be responding? Yes. But I don't think, that just ACE inhibitor would be it because if you think about it, ACE inhibitor, ARB, beta blocker, all of them are acting much further down in our pathway at the level of the receptor. As long as you have a connection which is a two way connection between the kidney and the brain, which is intact, and you're denervating it, if you have the nerve and you've denervated it, it should work.

Host: Yeah, because you're, you're inhibiting the feedback mechanism at that point.

Surya Chaturvedula, MD: That is correct.

Host: Wow. That's wonderful. Dr. Chaturvedula, thank you for being on today. I certainly learned a lot. There's no doubt about that. I hope our audience learned a lot as well. And for our listeners, if you'd like more information and to get connected with one of our providers, please visit carle.org. That's C-A-R-L-E.org. And also, for a listing of Carle providers and to view the Carle sponsored educational activities, head on over to the website at carleconnect. com. And that wraps up this episode of Expert Insights with the Carle Foundation Hospital. I'm your host, Dr. Bob Underwood.