WATCHMAN - Left Atrial Appendage Closure Device

Kevin Rist
Featured Speaker:

Kevin E. Rist, MD, PhD
Kevin E. Rist, MD, PhD, holds board certifications by the American Board of Internal Medicine and in Cardiovascular Disease and Clinical Cardiac Electrophysiology.

In September 2016, Aspirus Heart & Vascular became the first program in the area to begin performing the WATCHMAN procedure. This offers an alternative for people with atrial fibrillation (AFib) that have difficulty with blood-thinning medication. People with AFib often face lifelong use of blood thinners to reduce their risk of stroke.

Listen as Kevin E. Rist, MD, PhD explains that the one-time WATCHMAN™ procedure offers an effective alternative for those that are at high risk of bleeding complications or have had difficulties tolerating blood thinners.

Transcription

Melanie Cole (Host): People with AFib often face lifelong use of blood thinners to reduce their risk of stroke. The one-time Watchman procedure offers an effective alternative for those who are at high risk of bleeding complications or who have had difficulties tolerating blood thinners. My guest today is Dr. Kevin Rist. He’s a cardiac electro-physiologist with Aspirus Health System. Welcome to the show, Dr. Rist. I’d like to start with a little explanation of atrial fibrillation and tell the listeners what that is.

Dr. Kevin Rist (Guest): Well, thank you for giving me this chance to talk about AFib. It’s a particularly irksome problem to a lot of people as they get older. The normal rhythm, which we should probably talk about first, is that the upper chambers squeeze blood into the lower chambers--the upper chambers being the atrium and the lower chambers the ventricles. In so doing, they fill up the ventricles and help the ventricles pump out more blood and that seems to be the normal way that things should proceed. In atrial fibrillation, the upper chambers have a really chaotic rhythm. The rhythm isn’t regular. It transmits a rhythm that’s generally a little too fast to the lower chambers, and there’s no squeezing associated with that rhythm. Some of the parts of the atrium are squeezing and some of the parts are relaxing, and so there’s no net squeeze. So, it really reduces how well the heart works by at least 20%. So, the heart tends to be going too fast in AFib. It doesn’t have chance to fill up; and then, the atria aren’t pumping blood into it to fill up. So, it reduces what people can do. Some people get quite fatigued. Some people feel the extra beats or palpitations and the heart rate is very irregular. On the other hand, some people feel nothing at all. It doesn’t bother them and, of course, that’s dangerous too because we know that people in atrial fibrillation have a much higher risk at having a stroke.

Melanie: So, let’s talk about that risk of stroke. What are the first line defenses if somebody is diagnosed with atrial fibrillation and you want to reduce their risk of stroke, what do you do first with them?

Dr. Rist: Well, we try to define their risk of having stroke. There’s something called the CHADS-VASc score, and that’s an acronym to help us remember what the risk factors are. They include age, sex, history of hypertension, coronary disease, heart failure and previous stroke. When we add all those things up, we get a rough idea of how risky it is or how likely it is for them to have a stroke because of AFib. So, if you’re very young and you have no risk factors, you probably don’t need to go right on blood thinners. However, if you have more than one or two risk factors, you clearly need to be on blood thinners. So, that’s one of the first things we try to determine—peoples’ risk and, therefore, how reasonable it is to go on blood thinners. Of course, we’re not talking about an aspirin. We’re talking about blood thinners such as Coumadin or some of the novel, newer blood thinner agents.

Melanie: And, as there are other procedures that we could talk about in a different segment--rhythm control and rate control--if somebody cannot tolerate or take blood thinners, explain about the Watchman procedure and what’s involved in this?

Dr. Rist: Well, the Watchman procedure is--first of all, it’s important to note, does not prevent or stop or even treat AFib. It’s totally about reducing the risk of stroke due to clots that build up in AFib. So, it’s not a solution for AFIB. It’s a solution for people who have a specific set of problems, specifically with Coumadin or some of the other blood thinners. What sorts of problems? If they’re on blood thinners and they have problems with their balance or they’re very unsteady or they have multiple falls where striking their head would be a big problem on a blood thinner, then that would be one of the reasons to consider this Watchman procedure. If, on Coumadin, the regulation of their blood tendency to clot, their thickness or thinness, if you want to call it that, or the people who are already on this medicine know they want to get a protime or something they call an INR, if they can’t keep those well-regulated with the help of their doctor and alterations in diet, then they’re at risk of bleeding and/or having a stroke, and that’s not useful. If they’re blood is too thin, their INR or protime is too high, then they’re at risk from bleeding from the drug. If their blood thinner is too low or their clotting ability is not thinned out enough, then they’re at risk of having a stroke because they’re not adequately anticoagulated. So, the second person that this procedure is useful for is the person who can’t get their INR well-regulated within the range of 2 to 3 on the INR scale. So, you know, those are the most common, along with, then the third component of people who have bleeding episodes, either from their gut, GI bleeding, or sometimes bleeding from their nose. This has to be pretty significant bleeding but there are people who have problems with ulcers or bleeding spots in their colon or have terrible problems with bleeding from the nose. If you’re having bleeding issues all the time, then, obviously, a blood thinner is going to be very hard for you to tolerate.

Melanie: Dr. Rist, you gave us such a great explanation at the beginning about the physiology of the heart and how it beats, and this is a left atrial appendage closure device. Explain how this procedure works and what it really does.

Dr. Rist: Well, the blood in the right atrium, if there are little clots that form there, the blood generally goes to the lung and there’s actually a lot of natural anticoagulant in the lung. So, little tiny clots on the right atrium don’t really cause much of a problem. However, the left atrium is where the blood goes first to the left ventricle and then out to the brain, to the heart itself, to the kidneys, and the rest of the body. And so, clots there, small clots there, could cause a heart attack, could cause a stroke, could cause problems with kidney function. So, why would we have clots at all? Well, remember I talked about how the coordination of the atrium is very poor in atrial fibrillation and there’s really no contraction. There is a thing called the “left atrial appendage”. It’s sort of a worm-like structure that hangs off the left atrium and it’s sort of, probably the size of your thumb. When the left atrium is in a normal rhythm and the left atrium squeezes, this little thumb-like structure is squeezing also. So, it’s squeezing blood into the left atrium, and the left atrium’s squeezing blood into the left ventricle and everything’s very happy. But, as soon as you’re in atrial fibrillation, this little thumb-like structure becomes a backwater. It’s not an area where there’s any flow. It’s like stagnant water in a pond. That’s when clots develop, when there’s no motion of the blood. So, clots can develop and they can become quite large. It turns out the major strokes tend to come from clots that come from the left atrial appendage in people with AFib. So, if you’re on Coumadin, and your blood is thinned out, no clots develop there or are very less likely to. If you can plug that left atrial appendage and then your plug gets a lining on it so that it becomes as smooth as the rest of the inside of the heart, then no clots can come out of the left atrial appendage whether you’re an AFib or not. So, the idea of the Watchman is, it is a plug that goes in this left atrial appendage, this little thumb-like structure, closes off the neck of the left atrial appendage, and after a couple of weeks, six or so, most often prevents people from having strokes--the major ones that come from the left atrial appendage. And then, Coumadin can be discontinued.

Melanie: Is this something that’s permanent--it stays in?

Dr. Rist: Yes. It is quite permanent. It has to be. There are different size plugs for different size left atrial appendages. You cannot predict the size by looking at the person’s body. You have to do something called a “transesophageal echo”. People may be familiar with echocardiograms where they move or wander around the front of the chest and they get pictures of the heart. The left atrial appendage is right under the ribs in the front of the chest. So, because it’s under the ribs, just behind the ribs, we can't get a good picture of it with sound waves because the sound doesn’t travel well through bone. So, a transesophageal echocardiogram is when we take a tube that has an ultrasound recording device on it, and put it down in the esophagus, down in the food tube, and it happens to run right behind the back wall of the heart, right behind the left atrium. So, we can focus the ultrasound forward, and look at the left atrial appendage and we can measure its size and shape, and find out whether it would be appropriate for a left atrial appendage closure device before a Watchman. Eighty percent of the time, people will be appropriate, will have the right size and shape left atrial appendage to have this procedure performed.

Melanie: So, in just the last few minutes, Dr. Rist--and absolutely fascinating technology--wrap it up for is about the Watchman procedure, and what you want people that are suffering from atrial fibrillation to know about inquiring from their physician about this procedure.

Dr. Rist: Well, this procedure is for someone who has a high risk of stroke and has either documented bleeding episodes or has a lifestyle or problems with locomotion that would cause them to be at risk for bleeding or have problems maintaining Coumadin therapy at the proper level. If that’s true, this device can be implanted in someone who has the right size and shape left atrial appendage in a procedure that lasts one and a half to two hours under general anesthesia and then, you would go home the next day after a period of observation. Then, at six weeks, you would have another transesophageal echo, and that would determine if everything had healed well. This plug device has a little sort of a fabric covering on it, and once the body has put some cells over it, it won't allow flow anymore and then the risk of stroke is really reduced. The amount of reduction is equivalent to being on Coumadin but the benefit comes that you’re at the risk of having the bleeding episodes that go along with being on Coumadin. However, it’s not for everyone. You have to have a high risk of stroke and you have to have, as I said, reasons that you cannot or should not take Coumadin over the long term. After six weeks, if the device had healed in well, and 95% of the time it has at that point, then you get switched over to an aspirin and another blood thinner called Plavix. Then, at about six months, you get to switch back to an aspirin. So, there are many people who would like to get off Coumadin but you have to have some pretty specific reasons for it. This can be checked. You can go on a website and look up the Watchman, you can find out where in your area people would do the Watchman. Certainly at Aspirus, we do the Watchman, and the approach has been working well for our patients and we’re certainly happen to talk to anyone about it. We have an AFib clinic, and at the AFib clinics is one of the points in Aspirus that would lead you to the right people to get evaluated for this device.

Melanie: Thank you so much, Dr. Rist, for being with us today. It’s really great information. You’re listening to Aspirus Health Talk. And for more information you can go to www.aspirus.org. That’s www.aspirus.org. This is Melanie Cole. Thanks so much for listening.

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