Renal Denervation: A New Procedure for Lowering Blood Pressure

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Luke Laffin, MD:

My name's Luke Laffin and I'm a Preventive Cardiologist at the Cleveland Clinic, and I'm Co-director of the Center for Blood Pressure Disorders. It's my pleasure today to talk to you a little bit about hypertension and a new procedure that was recently approved by the US Food and Drug Administration to lower blood pressure. That procedure is called renal denervation. First with the basics, what is high blood pressure or hypertension? Blood pressure is the force that is exerted against the arteries in the body when the heart is pumping and then when it's relaxing. If blood pressure is chronically high, that's called hypertension and that increases our risk for four major things: strokes, heart attacks, heart failure, and kidney disease. Now, obviously no one wants to have any of those happen to them, so what are our options? Well, we start with lifestyle in everyone, low sodium diet, exercise, losing weight, all the basics, and then most people that have hypertension ultimately do need at least a medicine or two.

What happens when you're on three, four, five medicines and blood pressure is uncontrolled or what if you have all kinds of medication intolerances or allergies? We have certain patients who may have 10, 15, 20 allergies. They've gone through the gamut of blood pressure medicine. In that case, this is where a new procedure called renal denervation comes in. The important thing to remember when we think about the heart and the kidneys, because this procedure is done on the arteries that supply blood to the kidneys, but when we think about the heart and the kidneys, they're almost like a married couple. If one's not happy, the other one probably isn't happy as well. We got to treat them both right. Your arterial blood supply to the kidneys has a bunch of nerves around it, okay? And those can lead to all kinds of adverse consequences if there's excess activation of these nerves. We retain sodium, which then we retain fluid, it'll increase our heart rate and ultimately, potentially increase blood pressure as well.

Renal denervation is a procedure that's been under investigation for more than two decades, but then was approved by the FDA back in November of this past year for two different systems, an ultrasound based renal denervation system, and then what's called radiofrequency ablation system. I won't get into the details of one versus the other because they're very similar in what they do, but let me talk you through what that procedure and what a visit would look like if you're thinking about coming to the Cleveland Clinic for renal denervation.

So one, you're going to see one of our blood pressure specialists, just to make sure that you've been on appropriate medicines before, that it's true hypertension and not something what we call a pseudo resistant hypertension, and that we've ruled out more strange or rare causes for elevated blood pressure. If that's the case, then the next step is meeting with our interventional cardiologists, and we have three of them that have done a number of these procedures initially in the clinical trial space, but now commercially as well.

Then we would set you up for a procedure. And that's like any procedure or most procedures in the cardiac catheterization lab. You get a call the night before with a time to come in. You come in, you're lying on a table and a camera rotates around you. There is an injection of contrast via an artery in your leg to look at the blood supply to the kidneys. If that looks fine and normal, then a catheter, which is essentially just a long IV is inserted into that artery, the procedure is done. It takes anywhere between 30 and 40 minutes for the whole thing, and then nothing is left in the body itself. Everything is taken out, the procedure's done, the nerves on the renal artery are disrupted, and theoretically that should lower blood pressure. Most people in the absence of complications, go home that same day.

We've done a number since it's been FDA approved at this point and had very good response from patients and good clinical response as well. Now, a couple things to remember. Number one, the procedure in the clinical trials, in our experience thus far, is very safe. Anytime that you're going into an artery, there is a risk of bleeding associated with it, but that's very, very low and there's no need for any types of blood thinners or antiplatelet agents after this procedure, okay? Unless you're already taking them for whatever reason. The other thing though is important is how much blood pressure lowering should we really think about or expect in most people. If you are on three, four, or five blood pressure medicines, do not expect to get off of all of these medicines, okay? The average individual gets about between four and seven millimeters of mercury of blood pressure reduction, so what's that like?

That's about one pill, and so this can be very helpful in individuals who can't tolerate anything because of side effects and can be helpful in patients that don't want to add a fourth, fifth, sixth line drug. Now, there is a variety of responses. Some people can have a much more robust response or no response at all, and unfortunately there's no good clinical characteristic to tell us who's going to have a good response and who's not, but that's why it's good that it's a safe procedure.

Other things to remember about this procedure is that it's only a one-time procedure. The studies have not done multiple rounds of renal denervation and seen is that effective or not. So it's a one-time. And then what we typically do post procedure, once you go home is set you up for follow up, again within our Center for Blood Pressure Disorders, to make sure things are going well. Check and see what medicines you may or may not still be on based on how much blood pressure lowering there was, and then go forward from there.

Hopefully, I've answered some of your questions about renal denervation. As one of the best heart and vascular institutes in the world, I think we have some great expertise. We obviously have some wonderfully skilled interventional cardiologists who've done this procedure, and it would be great to see some patients that are interested in this procedure. Thank you.

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