Chapters Transcript Video Left Atrial Appendage-ology Dr. Chris Ellis discusses appropriate candidates for appendage closure and the LAA devices in research trials. Thank you very much for the kind introduction. I do, um, have to make a comment, Dave Adler definitely cleaned up nicely after the, uh, I think he had about a 12 inch beard for a while. I do. I don't know if that was here in Virginia or if that was, I just remember seeing pictures of you thought it was like he was lost in the wilderness. Yes. Different phase. I got it. Well, uh, first, um, just, it, uh, goes without saying to take a moment and just reflect on, uh, on the value of life today a little bit. Um, coming in from Nashville, you know, that's, uh, actually Green Hills is where I live. And, uh, we were, uh, familiar with, um, one of the boys that was killed, he actually was plays in our little league. Um, and it's really kind of shocking and, uh, tragic. So just kind of plots out to the families of Green Hills, Nashville and, and, uh, covenant school. Um, what, uh, they asked me to talk about is left atrial appendage, um, which is basically the study of a peculiar organ. Um, the left atrial appendage. We, we have uh gotten a lot more um science about this structure. Uh We know its clinical impact and now we have treatment options, you know, specifically targeted to it. So we're gonna go through uh a little bit of the basic science behind it, uh the physiology of it and uh and options both like surgical options, uh endocardial closure options and then future directions uh in the field, it's growing fast. Uh The left atrial p space at least estimated currently about a 30% annual growth rate for the foreseeable future, particularly with some large um head to head trials coming uh comparing orlan coagulation um versus the devices in like basically anybody with a IB. So we'll see. So most appropriate candidate for an appendage closure is somebody who's gonna get a appendage thrombus, right? Um Interesting this video, not entirely sure where that clot came from, but maybe it's crawling out of the left atrial appendage. Certainly a device in there wouldn't prevent this thrombus from forming if it formed on the tip of the ridge. But that'd be a very odd location for it. Um One thing we've seen is that, you know, really, there's a pretty direct correlation between the emptying velocity of the appendage that is how vigorously it contracts. Uh and the presence of echo parameters that predict thrombus such as uh spontaneous contrast sludge and smoke. Um patients with rheumatic disease certainly have a high probability of thrombus both in the appendage and in the atrium. Um but, but these are high risk people. So it's like if you're, if your chest is open in a micro stenosis case, you know, we really would think a resection of the appendage is an essential part of the treatment in addition to the valve replacement. Um, patients with a very low ef those have had an attempted surgical ligation but left a narrow neck seem to be a particularly high risk group of patients. And definitely for the EPS, you know, when we ablate extensively and end up with no electrical connection to the appendage, it becomes just a static um sink for thrombus. And you've seen even in the presence of anticoagulation, some of these patients will form pretty ugly thrombi interestingly, all those patients that are like those are the really high risk patients for forming a thrombus in the appendage and they've been excluded from every single clinical trial in the space. So, you know, like that's something to think about. Um lots of patients outside of your normal. Uh Chad's vast scoring. Uh you know, rankings are gonna be at risk and you know, if they have one of those prior um factors, but their Chad's vask is a one. You, you're not even thinking about putting them on anti coagulation maybe, but they could be the patient most likely to benefit from resecting or closing the appendage. The jazz vs scores. We've been learning is a weak predictor at best. The tool has a ROC of about 0.6 which is basically like it's an OK way to stratify for embolic stroke and a fib but it's really not that good. Um because there's so many other factors outside of it, right? It's easy to do and just kind of become part of the guidelines, I think because of its simplicity, like, yeah, you can check this box pretty easily and give them a score and say yes, Anna coagulate or not. But patients with like hypertrophic cardiomyopathy, thyroid storm various hypercoagulable states. Um Dynamic things we see this all the time in tee in the lab in ablations where someone comes in and then the appendage looks terrible, like full of sludge. You think it's thrombus, maybe you to board a cardio version. It depends who's looking at the scan. You give him a little bit of medication to increase contractivity. A little isopro a squirt of epinephrine, some fluids and all that spontaneous contrast clears. And uh you know, we find that there is no thrombus. So there's a lot of things there that are that are pretty dynamic as well. Myocarditis, probably another factor. The anatomy of the appendage itself appears to play a role. That's another thing I think that's important. It's not in the chad's fast scoring. This study. I reviewed this study as a peer review and then looking back, it's like really powerful and it seems underappreciated. But image B is the swan appendage, I actually had three in a row yesterday that I was that I was gonna do closure on. And uh they um they all had swan shapes which is difficult. But if you look at this patients in the overall population, patients with a fib and patients without a fib, uh the stroke rate in the swan is like three x higher than all the other. And we used to think of the chicken wing versus non chicken wing that impact is much smaller than swan versus the others. So why do we need left April pend closure? Um This is why. So here's a patient that was sent to me by one of my heart failure. Uh and general cardiology colleagues, coronary disease, a fib heart failure ef dropped in the setting of a fib. She really was pretty honestly, she was pretty healthy although she had some traditional Chad's Vask or points. So she had a four for Chad's Vask. Um but they didn't cardiovert her because of this scan. As you can imagine, you'd see Thrombus sitting in the bottom of the left atrial appendage, uh pretty obviously with dense smoke and sludge on top of it and then spontaneous echo contrast kind of flaking out into the left atrium. And she came in um a month after another round of anticoagulation still had thrombus. So we thought maybe we treat the heart failure first. They'll put in a cardiac resynchronization pacemaker. And uh cardioverter and her ef normalizes beautifully actually, like really nice, good up to lead position, you know, sort of left bundle area pacing plus a nice LV. Lead ef got better smoke we think is gonna disappear. So we bring her and schedule it gets card for a cardio version actually now to get her back and sinus rhythm. Um, unfortunately, this was in February last year and like a week before she was supposed to come in for um cardio version and possible appendage closure because we felt like she was very high risk for her current thrombus. Um She fell and died from intracranial bleed. So probably if she wasn't on an anticoagulant, she might have survived. We don't know. Um but certainly mortality after intracranial hemorrhage is extremely high, 35% in a week, 50% at a year and none of the anti coagulants are immune to this. But I think it may be somewhat underappreciated within the do ax that per DAXA actually has the lowest ran hemorrhage rate. It seems to be falling out of favor, I think for side effect profile because of all the G I issues, but really good anti coagulant has a reversal agent low IC H rate. Warfarin is the worst. As you can see, that's the green line on the top two. Not surprisingly. So, what kind of options do we have uh to address the appendage? So we kind of have the idea. All right, jazz vask, not a bad predictor, but there's a lot of other factors, anatomy, anatomy matters, dynamic factors matter and the appendage matters and, and you know, patients die from anticoagulant use as much as we want to say, we're saving lives by antic coagulating patients with a fib. So having an alternative is key, um we'll go through surgical and epicardial approaches, endocardial devices and then uh some experimental devices, the surgical closure ease. I would give it a, you know, a one plus, like not so easy. If you haven't done it before, it actually turns out really hard to do. Even if you're a good surgeon to surgically ligate the appendage effectively, it's about 65%. So 35% of the time there's gonna still be flow and it's because the sutures stretch out, it's dynamic. The thing starts beating again after you fill it back with blood. Uh maybe, maybe the, the pressure in the L A just stretches so much, it pulls the suture line and something opens up. But you'll see this where there'll be a gap back into the appendage. And you know, it's basically a giant kind of like an ink, uh electrically isolated appendage. You basically have this sack sitting there to fill with the clot and a and a nice little neck to enter out into the left atrium. So using the other tools now probably is a little more effective. We think the clip or the V clip it, it doesn't really move if you put it in the right place the first time it's gonna stick there tight and kill the appendage fast. And I'll show you an example of that. It's pretty nice. There's really one landmark randomized trial in surgical ligation, but it proves the concept that if we eliminate the appendage, we get rid of about 35 40% of embolic strokes. That's huge. Like just that alone. So, uh definitely there were issues with that trial, but I'm not gonna get into that. Most of the patients were still on anticoagulation even if they had their appendage closed. Which to me, it's like, well, what the heck? That's like the whole reason you do it. So, you know, to some degree, except if you had a mechanical valve, um I feel like the true impact was not really seen in Laos three in terms of mortality because everybody pretty much stayed on anti coagulation anyway. So here's when it looks really good, top left appendage is gone, right? It's basically a globe of the left atrium and it was tightly ligated on the right panel. You can see the yellow arrows pointed basically to the entrance into this large left atrial appendage that's still sitting there. And you know, nice spot though, if you're an interventional cardiologist, you know, you can imagine all kinds of different ways to close that off. So it's relatively easy to, to address that. But if you don't look, you wouldn't know. And even in that randomized trial, I was three, they did no imaging, they no, like close all these appendages, we have no idea how many of them were actually closed. So that's a problem. So make sure you image after surgical closure, clipping probably works better, more like 95% instead of 65%. And here's an example of why that would be uh nice. Left at appendage. I was going in to do a hybrid. A fibrillation attempted to lary it. But when I saw the approach with as I was coming at it, I was like, whoa, that's way too big. I can't even get over that. I mean, this is a huge piece of meat, top right video panel is in a fib and you can see how vigorous, I mean, that appendage is moving pretty good. Actually, it's probably got decent ejection velocity. It clearly has electrical activity. We clamp down, put the clip on. The appendage is like dead in, in a minute. You see it turned purple already. It literally turned black in front of your eyes. It stops moving because it's electrically isolated. So the clip is how you get rid of an appendage, in my opinion. Uh What's the data? The first data set was this was this uh sts registry showing just basically looking at anybody who had had intervention on the left atrial pen or not at the time of surgery not randomized data, but it showed about a 2 to 3 absolute 2 to 3% absolute risk reduction in stroke and systemic embolism. Um and all cause mortality for the patients that had the appendage managed. And so that was sort of background supportive evidence to the Laos three trial, which is this randomizing patients undergoing cardiac surgery with a history of a fib to either occlusion or no occlusion of a left atrial appendage. And you can see the inclusion group significantly better, 37% reduction in any stroke over a five year follow up period. Uh and this was on like 4600 patients. So pretty solid evidence in gonna be, I mean part of the guidelines standard of care 2022 and beyond a fib open chest, remove appendage in addition to whatever else you're doing. Uh ho hopefully that message gets out and like becomes the thing because we see a lot of times patients end up coming to us later. If they had an open surgery, especially valve patients, the atrium is really large, the appendage is large. Maybe they have some weird anatomy or you know, there's sort of a lot of stasis in the atrium and they end up ultimately stuck in an, in a situation where they have thrombus in the appendage, anticoagulate him. We'll see goes away, the age is too big to close with a device, then they bleed, they're gonna take them off, anticoagulation. And now they're stuck and nobody's gonna go back in that chest. So when you have the opportunity, it's really, I call, I mean, I'm always like keeping an eye out for that and a patient of mine is getting cardiac surgery for some reason and I hear about it, I'm like, make sure I throw a message to the surgeon and don't forget to clip the appendage. Right. So, pretty important. Now, another way to close off and kill the appendage from an epicardial approach is this system called the lat, uh which, you know, variably you may be aware of or not, but it's pretty elegant. I mean, idea you slide a wire up into the pericardial sac. You put a wire inside the left atrial appendage. The two dark wires attached are magnets. They're pretty strong magnets and they'll float around in the pericardial space and snap together pretty tight. And then over that you can advance a suture loop that's like a noose and you go over the neck of the appendage, tighten the noose, bottom left, tie the string, cut the string come off. Boom, appendage gone. So I mean, literally, now you see it now you don't and it, when it works correctly, it's really nice. It's probably better than or clip honestly, there's no, there's nothing left behind but a string of ethe bod. So for your nickel allergy patient, just a little tidbit for the implants and referring Larry, it can be done in anybody with nickel allergy clip. Like none of the endocardial devices. They're all night and all nickel titanium alloy with the clips, the old clip and the pro and the VC or the pro clip are OL but the V clip is actually Titanium only. So there is also an clip you could do in a nickel allergy patient. I learned that in the last year because it came up. So the weird thing with the uh lat is it hasn't, it didn't do a stroke trial. It did an a fib treatment trial and basically randomized patients getting an ablation to either uh close off the uh appendage in addition to catheter ablation PV I ablation or um just ablation alone. And uh this was a really good trial. I was part of the design of this. It ran for like six years. It was 600 patients treated. That's actually the biggest a F ablation trial by a mile that's been done like period and it was tight. The monitoring was super tight there. The data is really good. Unfortunately, our assumption of how poorly the control arm would do turned out to be wrong. Uh And as you can imagine, as technology has improved for sensing better ablation, understanding of biophysics, just like lesion formation. We've gotten better at doing PV I only just with RF. And so this was RF, not cry over or P FA. So control arm six, almost a 60% success at one year. And that's by multiple halter monitors, uh 24 hours and a lot of patients had loop records or, or pacemakers and we'd use that data as well. And then the Lariat plus PB I arm was 65% basically. So like a 5% difference between groups, we thought it would be 15%. So it technically didn't meet its primary end point. The, the final results are currently under review at the New England Journal, but the Larry, it worked really well. And actually the, the risk was low, the complication rate was 3% with Lariat, which was actually a lot less. And it's because like we had a protocol and it's like you follow the protocol, follow directions, do it right. It actually works pretty well. Um And you know, close to 85% of patients had zero leak. So that's actually better than Watchman Flex or amulet to have zero like 85 plus percent zero leak. When you did have a leak, there were little tiny leaks right in the center usually. And most of those, uh if you had to, you could put a little ad 02 plug in them. It's like piece of cake. Those are actually fun cases. Another one like the surgical, incomplete closure and post lariat leaks. I like those. It's all guaranteed 20 minute procedure and it's very simple and it's not a whole lot of metal like the divi the devices to plug them are really small. So there's not much surface area to them. They seem to be devoid of, um, you know, D RT risk of other things. They heal up fast. Um Well, we've looked deeper into the maze trial at the patients who had large atria and were persistent. A fib, it turned out there was about a 20% difference in the effectiveness of combination LARI plus. So we're working towards that and maybe some future trials, we're also seeing FDA may have an ear on this um for us because persistent a fib is tough to treat. And so anything we can find that actually proves out to be beneficial, maybe. Um so maybe Larry still has a future. So key points on that in terms of epicardial closure, again, surgical ligation, drop stroke risk, regardless of whether you image or whatever you do with anti coagulation. Now, if you image and you like only looked at the patients who had complete closure of the appendage, my guess is that number's better. And then if you stop anticoagulation and the patients who didn't really need to stay on it afterwards, the mortality data would probably also have have been supported because of the size of the trial. But it wasn't. Um again, Larry a little bit of uh improvement in the in the overall trial, possibly beneficial for subsets with large atria, early persistent A fib. Um But going forward, I think the main point on this part is again, closure of the appendage is should be in a standard of care for patients with a fib undergoing cardiac surgery. All right, that sink in for it now changing to what you're seeing way more often because it's extremely simple in comparison to doing an epicardial surgical closure of the appendage is the watchman or amulet or the endocardial devices for appendage closure. Um, the combined five year data on Protect which uh and prevail which was the watchman 2.5 the original Watchman device, you can see it on the top right panel, there's AC T scan where you see the device in the top, right and everything behind it is dark grayed out hasn't had, there's no flow, no contrast behind it. So that's a good device position for a watchman 25. And the whole benefit here when you look at across the board, pretty equivalent in terms of ischemic stroke with a tick towards Warfarin group doing better. That was mainly because 10 patients in the early phase of the Protect had air emboli and strokes that were attributed to the Watchman device if you go out past, if you say well, all right, we figured that out and this does not happen anymore. People don't get strokes from air Amli during watchmen, typically from seven days out that bar moves way over and it's like all that ischemic stroke great is really completely equivalent between the two groups, hemorrhagic stroke though, as you can imagine is considerably lower when you're able to discontinue warfarin. Uh And ultimately, that ended up uh favoring uh watchman in terms of all cause death. So, you know, and that's in, again, that's in accounting for um the complications of putting in the device which have dropped a lot. So the patients we're doing this in are higher risk. Like now, really, the chads vas score are most appendage patients by 4.5 to 8 to 5, pretty high risk group of patients in the early trials, it was a little bit lower risk. Uh but the if you compare the reduction in stroke rate, um you know, sort of like what you would have expected based on their Chava score and what the stroke rate actually was, it really looked pretty comparable to what we see with the Aristotle and Rocket A F trials in terms of reduction of stroke with use of a do A. Again, the safety thing being probably a large factor for why the early studies required three FDA panels and it was a long process before the device got approved. You can see it here. I mean, they really protect the F 232 patients at a 10% complication rate. Well, that's not probably gonna get FDA approval, right? But it got better and better. And this is what the old device, the newer device is, is significantly safer than the uh original device. This is the N CD R registry data again, sort of seeing like what's been going on out there prior to Watchman Flick. So this is like Watchman 2.5 is sort of in retirement phase. It doesn't exist anymore, but you'll still see patients with it and you may still see some patients with issues with it. I just had a really weird case of a period of ice leak on a 25 that was sent to me from Houston. It was like done four or five years ago. And uh you know, so there's still like patients out there with these devices, a lot of them 100 100,000 plus probably. Uh but the o but the overall any major complication reported in this registry was 2.1% with pericardial fusion being the main thing you worry about like puncturing the heart during the being in the appendage with the sheath and sticking the two Watchman 25 in there, which kind of had little daggers as feet and even with that 1.4%. Ok. It's not horrible. Uh And it continues to get better the design of the new, newer watchman. This is called the Watchman Flex. Um Oh my arrow thing doesn't work top right panel. You can see there's like uh the back of the device is actually soft, there's no pointy edges, that's a huge thing and it can fit in some pretty tough spaces better than the original device where you're really trying to finagle a sheath in there more than like a half deployed device. And that's a big difference because a bear sheath, sticking a bear sheath deep in the appendage is never a good idea, especially when the patient's moving around. Uh, you know, or, you know, we used to have to do these long breath holds when we put those old watchman devices in. Now, you know, you just, we don't even do that anymore because the device comes out halfway and it's just like this real squishy um contour and you can navigate that into the appendage wherever you need it. So the, the, the new version of Watchman got approved based on this study, it's called Pinnacle Flex. And this was uh basically 400 plus patients at experience centers with the original Watchman switched, gave him the new device, everything was tee guided for the implant and uh we really crushed it. It was like they made, but it was also, you know, Boston, the company was way on us to reposition, reposition, reposition the device. They wanted to make sure they tested that because we think they thought it was a lot safer plus really wanted to like not leave any leaks at all. So let's see why they did that. It's not a timer anyway. Um So in the trial with the 400 patients, there were zero device emboli uh embolizations which is great no pericardial fusions requiring drainage in 400 patients pretty good 0.5% major complication rate, 1.8% device, thrombus closure efficacy in terms of no leaks, greater than five millimeters was 100% but really about like zero leak at a year was around 90%. So 10% of patients still had some flow around the edge of the device at one year follow up. But that's like by far the best and even now it's gotten worse than that because people aren't repositioning the device as much as we did in this study. I mean, it would be like eight times and they were, even with that, the cases weren't that long because it was, you know, like 35 40 minutes, sure, you could do it in 10 minutes if you try. But, you know, if you reposition it several times, you're kind of watching it each time remeasuring and remeasuring. And so that kind of adds to the procedure time, even though the process of unsheathing and repositioning that device. Well, it takes a few seconds. So with that, you know, so 90% closing of these appendages, that's pretty good. A lot of the anatomies that we tackled in this trial were ugly. Um, like tough cases because the appendage has all kinds of strange shapes. It's really like, there's a fingerprint to it. Every patient is different. Yeah, I, I kind of throw, like the friendly appendage is top left. Ok. Basically any company, any device. Yeah, I mean, it's a piece of cake, right. This is like what they want to do if the appendage was that we wouldn't have all these like iterations of new devices because it would have been easy to close them all with whatever we were putting in there. But they're not like that. They have lobes hanging off like crevices. They may have variably uh enough depth to get in the, into the appendage may take severe turns like these chicken wings. And like I mentioned, the swan sort of has two different turns to it. So there's particular anatomies where changing the device design could help us quite a bit and flex is one and then Amulet is another one. So we'll talk about that in a minute. But here's an example of what would be re relatively difficult Watchman 2.5 case, pretty ugly, uh sharp turn shallow depth chicken wing. Like when we were doing Watchman 2.5 we would look at this and like half the time you just would abort, you'd see the te and be like, forget it, it's not gonna work. Um But you can see here, we're able to kind of like contour and squish this Watchman flex in there and actually get the thing closed off pretty well. Um We like to see that under the device, it's all kind of white and gray indicating that there's complete cavity elimination and fibrosis of the appendage underneath the device cap. So when you're doing follow up tees, if you see black, if you see a cavity inside the watchman or the device underneath the fabric, it looks black on echo, there's a leak, you gotta find it doesn't, that's not how this works. Occlusion leads to fibrosis and elimination of the cavity and it should be fairly dense. I've taken several of these patients hearts out at autopsy and heart transplant. It's like a hockey puck. I mean, literally firm rubber puck when it is total inclusion. Um Last comment on this was just like in, in this trial too. I will say like, I couldn't believe how fast a clinical trial could be done. This was like done in a month because those of us that have been like doing a lot of pings I probably had by the time we did this trial had probably done maybe 400 watchman and I had a ton of patients that had like terrible anatomies or I failed to attempt a watchman 2.5 and aborted it. And like we had all these patients stacked ready as soon as they rolled out the new device. It was like, I've got this patient, this patient, this patient, this patient, I mean, we do like 40 patients in a month at our center and I was like the fifth highest enroll enroll. Um This thing was done super fast and I think the main point of it is just that we took what was really challenging before and with device design, better training and more attention to detail during the implant made a very good success story out of some difficult um cases so it can be done. Um Next device to talk about is the other FDA approved device called an Amulet device. Amul declutter is a little different design. You can see there's two components to it. There's an attachment lobe which sits in the neck of the appendage and then a an inclusive disk that really when it contours right will just look like part of the wall of the left at it's very smooth, it sits out more proximal than the Watchman devices. So it takes a little getting used to. Um but the device uh now is approved based on the results of the uh clinical trial, comparing it head to head to watchman. So when you go in with this device, it kind of forms a little ball, navigate into the appendage position it and the lobe will take any number of various shapes. It can look funny uh like compressed and mangled top, right, bottom, right. You know, those are kind of bordering on too much compression of that lobe because it's a much more dense device. There's way more metal, it's not as compliant. Um And the anchoring mechanism is a little more I would say aggressive. Uh but in some cases that's good because you want to put it in a certain spot and you want it to stick there and, and this, this could do that. This is kind of what it would look like. Um Here's a patient who had a hodgkin's disease, a bunch of radiation to the chest small vessel disease. A little tiny 2, 2.5 millimeter stent in the circumflex. There is like the best marker I've ever seen for where to place the device, right? Um And there's an attachment cable and you can see as I release and counter clock, the cable, the disc goes into position. And as you watch this, you kind of can see the disc is moving with the left atrium very nicely. It's kind of like cupped and contoured and the lobe is kind of moving with the micro valve in the appendage. And so it has to, it like moves independently of each other, which can be helpful uh when you have weird angles to the uh appendage in the trials, the big trials, 1800 patients took a long time to it went from two different manufacturers. It started with Saint Jude Medical. Then during the trial, they were actually acquired by Abbott. There was retraining that occurred. There was a lot of complications early similar to the Watchman 2.5 studies. Um So this is like the same narrative patients were higher risk in this trial than they were in the protect and prevail trials. As you can imagine because they were like clinically indicated for Watchman to begin with. So the chad vas score is around 4.7. Uh but at, at a 45 day follow up in this hat as well. At one year, there are significantly fewer perry device leaks with the amulet device than there are with Watchmen. Um Mainly because really it's just a tighter, more inclusive device, it's just more dense and when it's positioned properly, the flow will cease much quicker into the appendage. The total safety endpoint was pretty equivalent between groups, but there are more procedure related complications with uh amulet. And sometimes we have to take that into account, uh mainly bleeding from, you know, taking elderly patients and poking a hole somewhere or repositioning the amulet a bunch of times before you kind of got that comfort level with it. Um because it was still, you know, like we didn't have a lot of experience with this. We had zero experience with it in the US when we started the trial. So you had to like start from scratch. So some of that's kind of baked into the data. Um the learning curve now kind of summarizing those three endocardial devices. There's the Watchman 25, which is a fossil now, but you know, the leak rates on it. Uh If you use the, I would say generous end point of a five millimeter or less leak rate 95%. Ok? In reality, like no leak. Hm. Probably in the 75% range of patients with a 25 are gonna have no leak. Uh, which is what you're ideally wanting to get D RT is something called device related. Thrombus. And I'll talk a little more about that for people. Maybe that don't understand that in a bit, but it's basically a clot on top of the device, it's totally counterproductive to what you're trying to do. You move thrombus from the left atrial appendage to on top of the Watchman, it is associated with strokes. And so we want the D RT rate to be zero. It's not zero yet because we're sticking a foreign object in the left atrium and a lot of times depending on where that is, it's also in a spot where there's a little bit of static flow because the, the PV flow comes flying over the top of it. And it's sort of like there's a back wash over the surface of the left atrial appendage, but it's not really a high flow area. Um But that, but the Watchman 25 is was really the gold standard for devices because it was the first FDA approved device, uh amulet looked like better on closure, slightly higher bleeding complications from implant. Um It's the, it was the more dominant device being used in Europe, whereas Watchman 25 was more dominant in the US. Um And I don't know the data on where that is now, but I'm sure that bar is always shifting. Um And then Watchman Flex, which is really the next generation of uh device, definitely easier, higher closure rates, better complete closure in the in our trial was 90% D RT rate a little bit lower. Probably because you could put it in a better position. It's probably position dependent rather than like anything specific to the material. It's the same material. Um and the trials ongoing that are gonna be very interesting. Option. Trial was a fibrillation. And then after a fibrillation or during a fibrillation, patients would be control arm or anticoagulation, standard treatment arm, they get a wash and flex and they could get the wash and flex during the ablation or up to like six, I think 3 to 6 months after the ablation. Uh So that trial is already done. It was 1800 patients. It's 18 months out. We should get data on that this year. Champion trial, another impressive trial to be done. Boston's done a great job with these. That's like uh 3000 patients randomized Doac versus Watchman flex and it's already it's already done. So complete enrollment and it's in the follow-up phase first, real primary end point is gonna be at three years. So we got a few years till we get data on that. But presuming that comes out even non inferior and better on bleeding uh probably makes it to the guidelines bumps it up a category if it comes back better and, you know, superior to anticoagulation in terms of cardiovascular mortality. Um that maybe bumps it to a class one. We'll see downsides to these things. Ok. So that was all the like, feel good story. And then there's the rest of the story. So the downsides are, you know, there's complications from implant and they can be fatal if you don't manage Pericard, a fusion, a big sheath perf I've been an expert witness on several cases. People die if you don't manage it, right. It's like fatal. Uh And that's the one thing that will get you if you're not careful outside of that. There's two things that happen that you are like, it's not your fault for the most part. One is clot on top of the device and one is a perfectly positioned device and implant. But then when you look at it, three months later, the device shifted and there's blood flow around the edge of it that does happen. So we're trying to like improve that some things on the device design, the fabric, we actually maybe can coat that with some uh clot resistant material that will help reduce D RT different design elements on the outside skeleton of the device or the device design itself like amulet or uh um conformal where there's a memory foam basically around the cage of the device. It could help choke off those little leaks that show up late and get us better. Uh total inclusion. These are what leaks look like. So when you see, follow up tes two images on the left, those are amulet, you'll see that. Sometimes you'll see a space between the lobe and the tissue and then the flow going past the disc and the lobe in the middle panel. Those are Watchman 2.5 leaks. Sometimes you'll see multiple leaks, blood goes in on one side, swirls around and comes out the other side and we'll see that a lot, there'll be like two leaks. Um Sometimes it's a two and fro single leak. Those are Watchman flexes on the far right panel that's like under the fabric because the fabric only covers like two thirds of the device. So if the device is pooched out too far into the atrium, blood's gonna go under the device or in the bottom, right. This is what happens more often you have somebody with a bi lobe appendage, the a the device anchors and gets stuck in one lobe. It looks great when you're hanging onto it by tee. But then when you release the cable, the force of that that you didn't realize pulls the device down and now there's a jet a flow over the surface. Sometimes, you know, one thing about the leaks is for a while, people said, oh, this wasn't any problem. Well, we've actually, we're the first group to publish a series of 1000 patients that we followed our ourselves and the Ohio state showing progression in these device leaks over time. You know, once there's a crack in your foundation keeps getting bigger and increased ti a and stroke rate over time in the patients with these small leaks because ultimately, you know, your cerebral vessels are somewhere in the 2 to 3 millimeter range. So there's no reason to think if something squirts out of there and it's two millimeters wide, it's gonna cause an event just like if you didn't have an excluder there, maybe it wouldn't be as severe. So we don't see like severe disabling strokes as much after watchman even when there's a leak uh because it's not a big clot that comes out of there, but stuff can still come out of there. Uh This was actually probably the more convincing story that um Mo Alcoy presented from Mayo and uh published last year on the registry of 50 plus 1000 patients. So pretty good huge data set, slight increased risk of stroke in the patients with a 0 to 5 millimeter leak. No increased risk in the patients with a greater than five millimeter leak. But it's mainly because if that's the case, what are you gonna do? Put them back on anti coagulation. So you, you eliminate what you would have seen in terms of an observed effect in the largest leaks because the operators or the following physicians put them back on blood thinners um in the ambulant trial, when you look, if you look at take out just the patients who had zero leak, 18 months, the stroke rate is 1.8%. That's really good. Um Most of the reason that the total stroke rate wasn't that good is bottom right panel, which is Watchman device 2.5 with a larger leak. So again, when you start slicing and dicing it, if you could get rid of leaks, you would really bring this like total stroke free survival curve down. Uh And that, that's something we're we're really trying to do. Repositioning is probably the most important thing. Matching the device to the anatomy is probably the second most important and then just better device design still is probably out there. Um When you look at true leaks, like if you do AC T scan versus a tee for follow up, you're gonna see all kinds of different things. This was a nice randomized study out of Europe really comparing amulet to Watchman flex and similar to what it makes sense. There's more leaks around a watchman than there is around an amulet. But there's more major bleeding from putting in an ambulance than there is with the watchman. And one of the weird things I've seen this about five times now, out of maybe 250 cases, place an amulet, everything's good. They come back two weeks later, big pericardial fusion and it's like sometimes it's serious sometimes it's, it's like inflammatory, the little anchors I think, penetrate the wall of the appendage and just they're under such constant motion depending on what they're touching. They may uh irritate cause pericarditis and you can get late bleeding. Now of the five or so that I've seen every one of them drained the effusion. It stopped, treat the pericarditis a month later. They were fine. So it's manageable, but it's annoying. Um As far as leaks on Watchman, one way you could deal with that is stuff it with platinum. These are coils like uh called Tao Coils company makes them, it's called the Azor Oil. They're basically super soft uh platinum. It's almost like liquid metal and you can go back in behind these leaks and just fill the cavity that remains with the metal. That's probably the best way to choke off the whole leak as opposed to trying to put another, some kind of other device on top of this. I've seen some interesting things out there like putting an amulet inside a watchman. Very bizarre. Personally, I wouldn't do that. This is what the, what the device would be like sitting in a heart model that I made from a 3D printed latex and you can kind of see the edges, right? That's a Watchman 2.5. You can see where there's a visible space by parts of the device, edge to the tissue and in the bottom right there. I've kind of like layered in, what a coil, the idea of coiling that you basically just, it's weird. It like, literally it's like cocking, like going to the dentist. You're basically filling a cavity with metal, uh, just kind of tuck it in tight so that it's not hanging out in the atrium and they'll endothelial as well. Um, so it's effective for closure, but it's annoying because it's a second procedure. We really want to do this in one procedure, right? The one thing with Amulet that's interesting is you can have a leak bottom left. You'll see Doppler flow up along the PB ridge edge of that disk and lobe. But the device is really well positioned. And what, what, what that is is just there's a some incomplete endothelial portion by a year. It's gone, it didn't do anything, leak disappeared. So it's the one thing that I like with Amulet over Watchman is like sometimes the leaks disappear. It's never that it's always the opposite of Watchman. Sometimes there's no leak when you implant it and it shows up later and you're like dang, so more to be done there sometimes Amy, it'll take funny shapes. This one. You see the top, right. It's kind of funny when you see that. Sometimes you might see that on echo on your follow up imaging where the fabric, there's a little piece of fabric inside the disc is flapping like an eardrum. It's like a little sail in there because the disc is so tightly pulled down that it opens up a potential space. And until that surface endothelial realizes the fabric in there can still sort of feel the left atrial pressure waves. And uh I've had people call me, you know, like your device is falling apart. What do I do? And I look at this and I'm like, it's perfect. Don't touch it. All right. So here's kind of a fun experiment that I did for the A I symposium this year. Kind of just to show a little bit about what the the difference is in the elision is acutely with these two devices to the left is the Watchman. The white fabric, the right is the um amulet. These are both like tight devices like there's no leak. OK. It's a Coke bottle. It's 21 millimeters and a half by 21 millimeters and a half. Perfect Ostium immobile. Like the best thing we could do is stick a device in and I created a little solution. That's basically the viscosity of blood and just like drip, drip, drip, drip and then I reversed it. So I wasn't like biasing right hand versus left hand and watch same amount of liquid on each. And you can kind of see just how it streams through the fabric on Watchman because there's basically just one layer of fabric and then the fluid goes right through and most of the fluid actually ends up hanging up in the amulet and very little of it gets through. So you will see sometimes something goes on and the patient comes in like a week later, two weeks later and you ct scan someone post amulet a lot of times you'll see zero contrast in the appendage already. Um So it's a little quicker to get to total inclusion. The other um sort of dirty underbelly of these devices is the D RT S and that's the device related thrombus, which can be pretty graphic well, when it occurs and, and causes a stroke. We don't wanna see that in this multi center study, we looked at the different things that would predict who's gonna get AD RT. And you can see hypercoagulable state, a pericardial of fusion probably because of interruption and anticoagulation. Like shortly after the device goes in patients with renal disease. And uh and when the device gets put in too deep, tend to have uh more device thrown by. So some of that's positional, some of it's just patient factors and why might that occur? This is a, a series of two patients from our Amulet ID E that uh one was uh died from a sudden death and one had a heart transplant, took them out, analyzed the devices, you know, they're really like, neither of them had a perry device leak really. Um But the watchman's about a year out and it's not completely endothelial yet. Amulet was about two years out. Same thing, the center hub is bare, but both of these like fibros and when you look at it under scanning electron micrograph, it's actually remarkable how much of the surface of the device still is pretty much bare. So the this idea that these things you pop them in and the end of the in three months. Not so sure about that. I think humans are different than dogs. Dogs can Elize pretty fast. Most of the animal models on these are tested in dogs and like they'll do these one month, two month autopsies or necropsies and uh see like beautifully white, you know, sealed um endothelium. My guess is that's the exception in a human until probably several years out and maybe never. We just don't have, we're building a larger series of these patients. Uh And it would be um great if you, if you hear of one, you know, just like somebody that had a device two or three years ago. And you know, and maybe you just knew ideally maybe a heart transplant patient and uh you know, shoot me a text, we'll get the heart. All right. So key points on these again, trials are on going head to head. No a versus device. So we don't have the answer there right now. It's a suitable therapy, appendage closure for patients who are indicated for anticoagulation but have high bleeding risk have had interruption in anticoagulation or other factors that make him a poor candidate to stay on anti coagulation. That indication labeling is likely to change in the next 3 to 5 years. Um The implant risks can be reduced, you know, with uh experience for sure, better training, better tools. And we'll see, we see that uh for example, with Watchmen, they redesign the sheath for implantation and it's really a lot better. It's very uh to and stable, it doesn't kink. Um the valve closes off, there's not like an air problem. So all those little things, all those little details matter, especially when you look at thousands of patients um better repositioning more uh frequent repositioning is important and the D RT thing is still a nuisance, but we're working on that one device that might be helpful. This is an investigational device, the conformal and here's an example, let's see, it looks, it looks different. It's kind of weird, it handles differently, it's really soft, it's basically like kind of like a watchman, two rows of anchors, but the underside is open just instead of like the watchman flex where they, it's a closed metal frame. So you can kind of like you can deal with these bifurcating appendages or like where there's a lot of we call them teeth. You look at it on the te and it's like it looks like it has teeth, like just gnarly areas where, you know, you know, it's gonna push the device back out, this can sit on top of that or sort of inter digitate in it a little bit. Um, the implant technique is very similar. These are a couple of patients that with their follow up. Te si thought looked really good and, you know, we'll see the trial is ongoing. It's head to head, uh, conformal versus either Watchman flex or amulet in the control group. It's up to the implant. So, sorry, last case, I'll leave you with just a reminder about the swan appendage. Again, high risk appendage. This is a 94 year old lady. Kind of an ugly appendage doesn't pump very much uh relatively static. The angles of this make Watchmen difficult to get a really ideal position. Um But going with the amulet able to kind of get up, turn down into that first neck place, the lobe pull back. This is with a steerable sheath, tilt the disc into a different orientation and ultimate ultimately end up with a very nice um position and she didn't, she did agree with that. Um I would have not loved that. I've had, I've had several Watchman patients with that anatomy where I've ended up just sort of like either too deep and tilted, too proximal and float, going around the ridge. It's just a problem for them. All right, final slide, I'll skip this. You can look at this later. This is a nice sort of like selection choices, different patient scenarios where these may be, um These may be useful. Uh you'll have it on the um slide deck. In conclusion, you know, here we go lots of options, endocardial surgical standard of care to remove the appendage. Lariat trying to come back from the dead. Uh Looks like there's some benefit in terms of a fib reduction, but it certainly is a good tool for high risk patients, intracranial bleed patients and particularly nickel allergy patient if you need to like get rid of the appendage. Uh Watchman 25 is like cardio XP. It's gone. Boman flex is the current workhorse. There's new generations of this coming that look really good uh treated devices to prevent D RT and really more like really more compliant devices to be able to deal with some of these more challenging anatomies emulate. We're getting experience with it. It's better in some ways, it's worse in other ways. Emulate two is the newer version of this, which will be coming soon in a trial similar to pinnacle flex. So design iteration to reduce the bleeding risk issue. Um and then conformal is an ongoing trial and I believe you guys will be a center here as well. So, um you know, and I think that trial once it gets, you know, a critical mass of implant or should enroll pretty quickly, uh because I've never been in a more enjoyable trial from a control arm perspective where I'm like, I can do flex or emulate. It's like I can do anything, you know, and, or you might get this other device, which is kind of neat and patients like they're like game for it, I think uh it's pretty easy to consent for it. Um, and I'll leave you with deep thought. 00 man, totally boof that um I was gonna say leave you with this thought, which is the largest leak I've ever seen. Ok. Um Thank you very much. Published June 9, 2023 Created by Related Presenters Christopher Ellis, MD, FACC Vanderbilt Heart & Vascular Associate Professor of Cardiac Electrophysiology, Director, Cardiac Electrophysiology Laboratory, and Director, LAA Closure Program
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