Well, welcome everybody to this session this afternoon. We're happy that you're here. I think there's some great cases that you're gonna be seeing today and I know just reviewing the slides, I learned a lot. So I'm excited for the presentations we're about to hear. This session is titled Going Leadless, a Case-Based Approach to Leadless Pacing in Challenging Cases. So if you thought this was something about AI or remote monitoring, that's down the hall. Thank you for laughing. That was very much a sympathy laugh, but I'll take it. Just some house cleaning. It's our pleasure, myself and Dr. Jamie Manluku, the other moderator of our session today. So we'll both be up here introducing and moderating, herding the cat, so to speak. But it's our pleasure to welcome you to HRS here in San Diego. This is hometown for me, so it's really exciting that we actually prayed to the sun and paid extra taxes and we have sunny weather. So we're happy about that for everybody and hope you get to enjoy San Diego while you're here. If you haven't already done so, please download the HRS 2025 mobile app from your preferred app store. Most of you have probably already done that. This is how you can participate in the live Q&A at the end. So we will have questions. We'll keep them toward the end when the last presenter goes. We have the last time frame for questions and answers. So when using the mobile app, log in with your HRS credentials that you will need to put in on the app. And please note that no video photography or still photography or recording is permitted. So without further ado, I'm happy to introduce our first speaker. Our first speaker is Dr. Mary Gleba. Mary Gleba, excuse me. Please come on up and I usually correct myself pretty quick, usually. Good, good. And Mary will be presenting to us the how and why of leadless pacing in adult congenital heart disease. Thank you. All right, good afternoon, everyone. On this sunny afternoon, we're all here. I'm flattered. So congenital heart disease. It's not starting. Oh, it's loading, okay. Lots of that we do in congenital heart diseases is off-label, so keep that in mind. But I am going to actually talk three quick cases and walk through some of the decision-making and the hows and the whys and the wheres and for these cases is kind of some teaching points. So we'll start off with a patient who actually has the ventricles and atria in the usual position, which is a gift. A 63-year-old female comes in with dizziness and near syncope. However, 23 years ago, she had a premium ASD and cleft mitral valve repair. She had a 31-millimeter St. Jude mitral valve and her ASD was closed. And subsequently, not uncommonly, she got chronic atrial fibrillation, had some bradycardia, and needed a pacemaker. And you can see from the chest X-ray, she needed more than one pacemaker. Prior pacemaker was on the left and at that time, the decision was made to just leave the lead in place. She had a lead and system placed on the right. But now we have trouble. The lead's 15 years old. The impedance is up. She's essentially dependent. You know, the attempt was made to program unipolar and hope that we could buy some time to think and then she had inhibition. So have to make a decision, have to figure out what to do. Her EF was low normal and of course, she's anticoagulated due to her mitral valve. So the decision was made to actually go ahead and do a leadless device after that venogram from the right side, which is shown on the left-hand portion of the slide. And although it looks like that vein connects up, that is not the subclavian vein and it connects to the hemiazgous and through these tortuous collaterals, the venous blood drains, but there was no direct way to get into her heart. So extraction was contemplated, was not particularly attractive to the patient who had some medical frailty issues. So the plan was to go ahead and place a leadless device and it was a straightforward, transfemoral leadless device that she did well with. And the decision was made then to leave the pacemaker generator on the right side and come back and deal with that later. So luckily, she did fine with this, but we're still left facing, as we do in congenital heart disease, that these devices lead to other chronic patient concerns and indwelling leads, but that's a discussion for our extractionists. So she did well, four chambers, everything's in the right location. We got lucky and that was great. But next we have another patient and this patient has Epstein's anomaly. And so a 45-year-old female, known Epstein's anomaly, but again, 23 years ago, had a prior tricuspid valve repair. And as what happens in Epstein's, patients can then develop subsequent tricuspid valve problems. And I put up these images because I really like them and the sketch on the upper right kind of shows from a surgical text the relationship between the atrialized tricuspid valve, the traditional place of the mitral valve, and then her aortic and pulmonary valves. And I like that little surgical sketch because it shows you just what part of that right ventricle actually squeezes and is true ventricular myocardium. The cartoon next to it kind of shows what these atria really look like. They're enormous, they're slow flow. The annulus for the AV node is in the usual position. And arrhythmias are very common in patients with Epstein's anomaly, whether it's WPW or ventricular arrhythmias or other things. And one of the clues you can look for is on the electrocardiogram, which I showed a representative one below, shows two to 180 block sinus rhythm and a right bundle branch block. Kind of one of the tenants in Epstein's anomaly with congenital heart disease is if you do not see a right bundle branch block, think WPW, think multiple pathways, think weird pathways because they get it all. And the schematic from the CT scan actually shows you the physiology of Epstein's anomaly with the pressure overload both on the right side for the right atrium into the left atrium and the ventricular septum. So also in today's world with social media and with private groups on social media, the adult congenital patients are very empowered and they're empowered in their healthcare and that's wonderful. And so she tells us when she comes in as the plan is for surgical treatment of revalve, I don't want a pacemaker. I have friends who've had these. I don't want it. I want a leadless pacemaker. Is that possible? So this is kind of one of these off-label uses of technology that we do in congenital heart disease. So how do we deal with this? Well, we started thinking about it. Obviously, this was a discussion with our surgeons because it's done open at the time of heart surgery. Can it be done? Yeah, because the surgical approach is right there. And so this is actually the approach that's taken. The surgeon approaches the heart through a right atriotomy on the right-hand side of the patient and then through the tricuspid valve, they can deliver the catheter and the micra in this case, retract the sleeve, unlock it. They do a little tug test with forceps and then they check. But of course, they do this prior to replacing or repairing the valve. And so you can't do the electrical testing until you're off cardiopulmonary bypass and you've rewarmed. Of course, you need to check again afterwards. So this was a rather slick solution for this. Our surgeons were gung-ho. We've done a few of these. But what I really wanna show you is this video that comes from Cardiothoracic Surgery Journal where they did this lovely movie intraoperatively of how they did this. And I just thought their images were pristine. So there's the catheter coming up. You can see that there's the chordate from the valve. They're aiming for the septum. Now they're withdrawing the delivery sheet. And I mean, it makes it look short and simple. There's the tether and you can just kind of see that those DeBakeys or forceps coming in, pulling on that tether to make sure that it is secure. And then they clip it and basically that's great. Now this isn't an Epstein's patient. These images are great. But you can see the intra-op TE and the 3D that the leads where it's supposed to be. However, not always is this perfect. So here's another video intraoperatively. I'm sorry, I think I have to, yeah, this is the second video. And so here's a situation where they do the same thing, forward pressure to get the tines to engage, the tines don't engage, the lead dislodges, they have to repeat the process. But they still are able to get the lead in and direct visualization is a great way to do this and it worked. So a nice solution for a young Epstein's patient. So this is where those videos are from. It's from a small series of 15 patients. Some of these patients also required lead extraction from prior pacemakers at the time of their surgical tricuspid valve intervention. But the interesting thing is the surgeons doing this were also able to avoid using any temporary external pacing leads. So it's out there, it's been done. I think that it is doable and it's nice to have this option. So my last case is way more challenging. This is a patient that we were asked to see. Comes into the ER with an elevated heart rate and the primary team calls us and said, oh, he's had heart surgery in the past and he's had an ablation. But you should look at the chest x-ray because it looks kind of weird. I'm like, uh-oh. 39-year-old guy with prior heart surgery? Okay, those are clues. And so there's his telemetry strip of a narrow complex tachycardia and my arrows don't show you the P waves but there's some P waves or atrial activity buried in there but here's his chest x-ray. Okay, so I can tell you for sure that the left chest does not have the heart. The right chest has the heart. He's got sternal wires. He's got veno-veno coils in there and implants are devised. I'm thinking, oh boy. So we need to do some digging and figure out what to do next. Okay, so prior heart surgery. We were able to get his prior op notes. Well, he had a Glenn shunt and he had an extracardiac lateral tunnel fontan but this was many moons ago but he had an ablation at some point and the ablation, 20 years ago, they were able to get into his atrium via the fenestration. Said, oh, wouldn't that be nice if that fenestration were still open? We could put a catheter up there, do a little mapping and do our ablation. Well, I wasn't so lucky and then, of course, he had bradycardia on telemetry so not terrible but he was bradycardic so clearly, we had to do something and so what do we do? Well, reviewing the prior data is crucial in congenital heart disease. What was their access? What did they do? What did they find? And we had to obtain kind of updated imaging so we did our 3D heart CT scan. This guy has dextrocardia with complete situs, situs inversus, huge liver on the other side so we had to start having these discussions, the planning of how are we gonna get him through this and one of the key decisions in this case was a discussion with our anesthesiologist and he had upfront inotropes and vasopressors. You ever take care of these single ventral patients? They really have trouble for long procedures and sedation and this little schematic showing 20 of dobutamine, we were on 25 of dobutamine. I think it's my personal record and then we had to figure out how are we gonna get from this closed fontan into his pulmonary venous atrium? So we had initially planned to do this with a transeptal or a transbathal or transfontan approach with RF. That did not work and this required then doing the standard puncture but then using an Evercross balloon to dilate up the hole and get the dilator to go and eventually an Agilla sheet. So what about the bradycardia? Well, the initial plan was to say, hey, maybe we can do a transfontan leadless pacemaker but after the trouble we had trying to get the eight French, eight and a half French Agillas in, there was no way we were gonna get a bigger sheet in. So the importance of imaging, sorry. So I wanna show you, this is the 3D printed heart that we did and I was going to bring it but it took up half my suitcase so I didn't and the white is the ventricle to the right of the chest, the pink is the fontan, the dark pink is the aorta and the blue is the pulmonary venous atrium and the middle panel shows why we had them transect the ventricle so you could look up from the ventricle and see into the heart and the atrium and see where that fontan is and the other view is a posterior view of the chambers and so this was really useful for us to kind of get a 3D sense of what we were ablating. So fortunately he didn't need a pacemaker and because we weren't able to do it at the same time but we had to come up with a different plan. He preferred not to have his fourth or fifth sternal splitting operation so we talked to our interventional folks because they do transcarotid TAVRs. So this is a case report of a transcarotid approach and a single ventricle, single right ventricle for leadless pacing and so the first frame A shows the wire down, the second frame shows the sheet and then this shows delivery to the septum of this anatomic but systemic RV for transfontan pacing. So these things are coming. So what are the guiding principles to get through a case with congenital heart disease? Well obviously patient selection. You've gotta do your homework, gotta talk to them and we have to have shared decision making because clearly putting any type of lead in a systemic ventricle, you know, first of all, unknown long-term stroke risk, anticoagulation's mandatory, they have to be aware of that. Preparation is key. I don't know how many people I talked to about getting this case done and what we needed to do. Intra-procedurally, the anesthesia management is super important so you get your cardiac anesthesiologist with you on the team and they were phenomenal but imaging, we used every form of imaging, TE, CINE and then we were attempting to use ICE and of course micropuncture. So I think that especially in leadless pacing and especially in congenital heart disease, there may have some periprocedural risk. Certainly if you have to go on cardiopulmonary bypass because you're in trouble, well you need your surgeons and that increases periprocedural risk but we hope that long-term, leadless devices in these young patients who have decades in front of them will have fewer complications. So in summary, hybrid approaches for pacing may be necessary both tachyarrhythmias and bradyarrhythmias coexist. Pre-procedural planning is crucial. You have to do a team approach like we do and I think leadless pacing offers a new option for these patients in select situations but we don't have any long-term registries. So a quick question for the audience. Anybody implanted a leadless in someone with congenital heart disease? Oh, great, a few folks. So, okay, I'm gonna skip over that. So if you're interested in that, this website is coming soon, leadless pacemaker ACHD. There's my email and I'm happy to collaborate. So thank you for your time. So that was excellent, thank you. I think the next time I have a hard day in the lab, I'm just gonna think about the types of cases you have every day and feel better about myself. For the next speaker, I'd like to introduce Dr. Aaron Bender from UCLA who's gonna talk to us about the list in the context of tricuspid valve disease. All right, well loads, I have no disclosures. I am a failure of capitalism. There is nothing better than watching cases like that and every time you feel slick in the lab, realizing you're playing the game on easy mode. All right, so we're gonna somewhat issue the case-based approach and talk in a more general sense but the prompt was the how and why of leadless pacing in patients with tricuspid valve disease. So we'll go through some anatomic considerations with respect to implants. We'll talk about leadless pacemakers and their implantation, including looking at some pictures that we've already seen. We'll talk about other options for implantation in this case, again, I'm gonna be coloring outside the lines a little bit. And then if we have time for it, a brief interlude from someone with some lead extraction perspective. First and foremost, it's really important to note that tricuspid regurgitation at the forgotten valve is the thing we all sort of ignore, is not benign. I think we often criticize studies for having too healthy a population. This is 613 fairly healthy patients in Japan. Normally Fs, hemoglobin not too bad, not a lot of renal disease, not too old. And importantly excluded, quote, significant, greater than mild left-sided valvular disease. So 25% rate of death at three years. This is not something that should be ignored. It's something that we really need to pay attention to. That may be more a question for our structuralists, but that's a different talk for a different conference. And there's really two considerations in these cases. One is management of AV block after tricuspid intervention, so block caused by either surgery or a transcatheter approach. Or managing TR in the setting of pre-existing device, that's more lead extraction talk, and we won't talk about that too much, but both of those flavors matter. With respect to anatomic considerations, here's a beautiful dissection from our wonderful anatomist, Shunpei Mori, who's an absolute gem. An REO view with a cutaway of both the free wall of the right atrium, the free wall of the RV up to the RVOT, and a significant portion of the tricuspid annulus. And so for the relevant anatomy here, you can see highlighted in the square, transilluminated, the membranous septum, an important landmark for the conduction system because the penetrating His bundle passes through there, and you can see that highlighted by the AV node there, which only shows up on my screen, fantastic. And then to the right with the McAlpine image, you can understand why tricuspid intervention is so risky here with respect to the need for pacemakers because your conduction system runs right between that aortic root and the septal portion of the tricuspid valve. So it is no surprise that these result in a fairly high rate of need for pacemaker. From the EVOKE trials, there's about 20, basically one in four, one in five patients have a need for pacemaker after implantation. That's excluding patients who previously had a pacemaker. Unsurprisingly for triclip, not much of a risk, if at all. And for surgical, either aneuplasty, about a 15% risk, and for tricuspid replacement, about a 20% risk. So a lot of these patients will end up needing pacing. So you have to think about what your options are post-valve, and a lot of these patients come in with a preexisting need for either pacing or defibrillation. So the options are a leadless pacing system, that's obviously the subject for this session. Transvenous system with coronary sinus leads, not passing through the tricuspid valve, lead or leads. Epicardial pacing systems, especially for patients going for surgery. I think we're gonna try to reclaim the term POTS, but a plain old transvenous system, and especially with conduction system pacing. And then for patients who need defibrillation, yeah, you can put the ICD lead elsewhere in the MCV, but either an EV or a sub-QICD, plus minus leadless pacing in that circumstance. But as leadless pacemakers get more sophisticated, there's another challenge that comes up, which is so has conduction system pacing. And so in these patients with tricuspid valvular disease and a pacing need, you're sort of stuck between the options for leadless pacing and all of its benefits, and especially in this case, minimal valve interference, room for valvular intervention, or conduction system pacing, and obviously I don't have to speak to a room of VPs about the benefits of conduction system pacing, but this actually is a genuine dilemma, and something you need to think about, and obviously with the potential for conduction system pacing out of a leadless system, that may alter this math a little bit, but it's calculus you have to think about. Just a very brief overview on leadless pacemakers. Again, nothing new for anybody in the room, but nanostim hit the market in 2012 for a brief cameo before making a disappearance, mostly in pulmonary arteries. The micro came out about a year later, and has been on the market since. Followed several years later by at least a chance at having AV synchrony via the micro AV, and then more recently now, the ability to have dual chamber leadless pacing, which really does make a difference for the options available for these patients, and how we think about it. With respect to timing, so one option is preceding transcatheter intervention, obviously in a patient with known tricuspid disease, and a pacing indication either who will undergo extraction, or is planned to undergo both, you can certainly implant a leadless pacemaker ahead of time. The option for concomitant, which introduces two potential interactions, both having a fresh implant and a new valve, or the other challenging interaction being the electrophysiologist and the structuralist. There's also potentially reimbursement questions, but that's not really a question to address. And then of course, directly at the time of surgery, I have still images, you've seen a video, I'm gonna move on, but again, the point that this can be done safely and effectively using the delivery sheath during surgery, and you can actually view it at the time, and visualize it in tug tests, or ultimately following transcatheter intervention, especially in patients who develop a pacing need in that circumstance, and we'll talk about best practices for that. So there are a couple of geometric considerations here. The average right ventricle, so studies measured by echo, typically in a long axis view, are about 65 to 70 millimeters. By CT, it's more like 80 millimeters, and that's from the true apex to the valve plane. This becomes important when you're implanting a 38 millimeter long device, like an Avere, or a 26 millimeter long device, like the Micra, especially because in the case of an evoke valve, the valve is expected to protrude about 10 millimeters beyond the annulus, and so you have to keep from interfering. That red dot there's supposed to represent the moderator band, which in most patients should be right at about the midpoint. And so if you have about an 80 millimeter ventricle, and a moderator band at about 40 millimeters, and you're implanting a 38 millimeter long device, as long as you get, or 26, as long as you get it beyond the moderator, depending on geometry, depending on what you've attached to, obviously lots of caveats, that should help prevent interactions with the valve. And there are a couple of case series, and then systematic review showing really minimal TR, or worsening of TR following needless implantation. This is also a good argument, by the way, for a good RAORV gram to delineate that sort of free space at the apex before implantation, and then also to help you make sure you've got enough room to spare the valve. There are radiographic considerations. So in most people, the long axis of the heart lays at about 45 degrees, not in your patient. Therefore, your best imaging, in order to get a short axis view, would be 45 degrees. And the heart lies in three dimensions, and so typically, you're about 10 to 20 degrees off the horizontal axis as well. And this matters if you are trying to implant a leadless device following some form of valvular intervention, or trying to avoid dislodging the valve, or interacting with the valve. So a great paper with images from, I think from Europace from last year, but demonstrating their sort of key points for implantation, but lining up your approach in an RAO view, again, getting a good long axis, getting up close to the valve, and then finding the right individualized LAO view from those last views, you'd figure about 45 degrees, and 10 degrees caudal, plus or minus. Trying to get yourself so that you can actually cross the valve without too much in the way of interaction. And then passing back to an RAO view, and going for the implant, again, remembering the length of the device, the size of the patient's ventricle, and making sure you leave enough space to not interact. So ultimately, both anatomy and angulation in these cases end up being very important. From a lead extractionist's point of view, if you have a case with pre-existing TR and leads, this is data from Bruce Wilcoff and friends, and I'll skip to the most important part, but in patients with pre-existing severe TR, there is about a 35, 37% chance that the TR will get better with extraction of the lead, and obviously, again, that's a whole nother talk on figuring out who's the right candidate, and who's likely to improve. And of course, you're taking a population of patients whose TR could only get better because it's already severe, but there is a possibility that you will prevent needing tricuspid intervention like this, and then you can implant the leadless pacemaker to follow if it is the appropriate device, and hopefully preserve the TR. And now to completely go off the rails, one more question. Is it a crime to implant through a prosthetic valve? So this is something all of our surgeons, I think, prefer not, some, occasionally you'll find somebody who's okay with it, but usually you hear for the consult after tricuspid replacement, do not put a lead across the valve. There's not a lot of data, but for the data there is, it does not look like there is long-term worsening prosthetic valve function. So here's a study of 58 patients undergoing surgical replacement, and the comparison of either moderate or worse TR of the prosthetic valve after pacemaker implant with either a pacemaker or ICD lead across the valve. And a similar study of 46 patients, and again, some of these were ICDs, and there was no difference in valve dysfunction in 5.5 years. So it adds another complication to this, which is how badly do we actually need to be avoiding this, especially in the era of conduction system pacemaking where we know there's significant benefit in that regard. And finally, one last plea, please don't jail leads. Again, a topic for a structural talk, but there's a significant rate of valve dysfunction, or of lead dysfunction, especially following transcatheter valve deployment. And then you've taken a patient who was previously not a surgical candidate, hence why they're getting a tricuspid intervention via catheter, and now they have a lead that if it gets infected, basically, more or less has to be dealt with surgically. So anyway, a few key points. Leadless pacemakers, especially now with dual-chamber leadless pacing, offer quite an effective option for pacing in most circumstances. Implantation can be performed safely, timed essentially however you want, what makes the most sense for the patient. And as always, consider and evaluate your anatomy and your geometry during implantation, and use your preoperative imaging to help you locate. And then finally, just a couple of points. We probably could use some more data on whether we really should be avoiding putting transvenous leads across bioprosthetic or transcatheter valves, but again, another talk for another time. Thanks. Thank you. Thank you, Dr. Bender. Pleasure. Thank you, Dr. Bender. Our next speaker is Theofani Mela, who is going to be speaking to us on the how and when of leadless pacing in lead extraction patients. Excellent pronunciation of the name. Thank you very much. I was practicing. I also have to say that we also pay high taxes in Boston, but we don't get the good weather, so you probably have got a better deal here. It's thinking. Hi, everybody. So the how and when of leadless pacing in lead extraction patients. I will start, and I thought that I had a complex patient until I heard Marie's case. So this is a simple case of a 71-year-old man with a long history of surgical AVR, redo AVR with root and hemiarth replacement in 2013, sick sinus syndrome somewhere in there with a dual chamber pacemaker implant in 2015, infection, endocarditis, explantation of that original pacemaker, which was on the left, and then re-implantation on the right, and subsequent TAVR because of malfunction of his AVR, who was transferred to our center after he collapsed. The interrogation of his ICD showed monomorphic ventricular tachycardia, and he was transferred to us for lead extraction of the pacemaker, the right ventricular lead, and an upgrade to a dual chamber ICD. At that time, he was not receiving a large burden of ventricular pacing. His ejection fraction was 45 to 50%, and upon his transfer, we got the impression that he had been quite hypertensive during his hospitalization, and they were trying hard to manage his blood pressure. So we thought that this was a quick procedure, that the next day would return to their referring physicians, their referring hospital, but things did not go as expected. So we took him for a lead extraction, and upon the induction of anesthesia, he developed extreme hypertension. The anesthesiologist thought that this was a case of hyperthermia, so the case was aborted. The workup subsequently showed pheochromocytoma, and a couple of weeks later, during the same hospitalization and all the effort to control the blood pressure, he underwent a successful resection. Unfortunately, during that same hospitalization, he developed bacteremia from lyme sepsis and endocarditis, and his TE showed atrial, the AV involvement, and possibly aortic root abscess. At that time, he had become pacemaker-dependent. The surgeons, however, did not want to take him for surgery. This was going to be his third or fourth valve replacement, and they wanted to treat him for six weeks with antibiotics, let him cool down, and then do the surgery. And in the meantime, we had the consideration about what to do about the original reason that he came, the pacemaker extraction and upgrade, and also now the additional consideration that his pacemaker needed extraction due to the endocarditis. So a lot of discussion went back and forth between the different teams, and the options we considered were to wait for six weeks on antibiotics while maintaining the same pacemaker system, and extract everything at the time of surgery, and then think what new system we would give him. The second option would be to extract the existing system and give the patient a semi-permanent pacemaker for a few days until he received some antibiotics, and then consider or not maybe a leadless pacemaker as a bridge to the cardiothoracic surgery. A third option would be to extract the supposedly infected pacemaker system, and implant a pacemaker, a leadless pacemaker, right at that time, same procedure. And one other thought was to extract the dual-chamber pacemaker and upgrade to the ICD, which was the original plan while he was being on antibiotics. And this is an approach that has been supported even by our ID colleagues as long as the patient is not actively bacteremic. But I can tell you this last option, while the patient had a root abscess, was not really a good option for us. So really the question was whether with the extraction to also provide with a leadless pacemaker as a bridge to surgery with the implantation during the same day of the extraction procedure or wait until later. So we know from multiple data by now that having a leadless pacemaker reduces for the patient the risk for infection remarkably. This is a collective 3,000 patient study where the infection was really extremely low, almost down to 0%, and trying to explain why leadless pacemakers don't get infected. There are potential reasons that include resistance to infection due to absence of a subcutaneous pocket and leads, less manipulation by the operators, gloves and hands as we implant, as well as the size of the device, the location and the material that the device is being made. Even in the highest group of device infection patients, the dialysis patients, the incidence of leadless pacemaker is really extremely low, almost down to 0% as we can see in this registry with zero infections in 201 dialysis patients. The data also from the NanoSteam Avair pacemakers with a leadless one that showed no infection in 31 patient and the leadless two trials with one infection in 526 patients are quite supportive. And then the question, what happens if we implant the leadless pacemaker at the same time as the extraction procedure started being answered initially with case reports and then small series that keep getting larger now, but the first small series was in 2020 when 17 patients with actually active endocarditis, some of them even actively bacteremic, received leadless implant at the time of the extraction and then up to 143 days later, there was no infection in the system. And even after midterm follow-up of those patients with the addition of others, four years of implants, 86 patients, 76% of them with active bacteremia at the time of implantation, extraction and concomitant leadless pacemaker implantation and during a median follow-up of 163 days, really no recurrent infections. So we had pretty good evidence at the time of our procedure that even if we implanted the leadless pacemaker at the time of the extraction procedure and by that saving the patient one more procedure which would have been after we implanted the semi-permanent, bring him back to the lab days later for the leadless procedure, that would be safe for him. And this is what we did. So the right-sided device is gone and a leadless pacemaker was implanted. During actually the extraction, the TE showed that the root abscess was quite scary looking and actually the surgeons decided a week later to take him back to the operating room and replace the aortic valve, all the three prior valves and actually a couple of days later, after they had left the chest open because the patient had really become so sick from infection and prolonged hospitalization, brought him back to the operating room and did not remove the leadless but implanted an epicardial system, a dual-chamber epicardial system with the ventricular lead being on the left side. So really providing LV pacing with a dual-chamber device. Subsequent follow-up of the patient, remarkable recovery. His ejection fraction, which at the peak of the sickness was as low as 43%, now up to 55% with LV pacing. That original discussion about the monomorphic ventricular tachycardia, which as you remember was the first thing that brought him to the hospital, a lot of thought was put into that and there was a high suspicion that this was really a manifestation of the pheochromocytoma. So almost a year after his original presentation, we did an EP study and there was no inducible ventricular tachycardia despite very aggressive stimulation. So we maintained the dual-chamber pacemaker system but we had as a backup the option of implanting a subcutaneous ICD. And we have maintained the leadless pacemaker. The epicardial system has been working well but with rising pacing thresholds. So for a pacemaker-dependent patient, always a relief to know that you may have some backup pacing if ever the epicardial system fails. So implantation of a leadless pacemaker at the time of lead extraction is safe and feasible. Implantation of a leadless pacemaker during active infection and at the time of lead extraction is safe and feasible and the risk for leadless pacemaker infection is exceedingly low. Thank you very much. Thank you. Our next speaker is from Cleveland, who's gonna talk to us about leadless pacing in patients with ICD indications. Hi, good afternoon everyone. Thank you to the organizers for inviting me. I also have nothing to disclose and the topic that I was gonna speak about today is leadless pacemakers in patients with ICDs. We'll start with a clinical case. We had a 79-year-old male with a history of CAD, multiple PCIs, ischemic cardiomyopathy, history of an ICD, inducible VT, and therapies who actually underwent a elective generator replacement. And unfortunately, 10 days post-procedure, he comes back with bloody imperial and drainage, gets a course of antibiotics, doesn't improve, and eventually undergoes an extraction procedure for his dual-chamber ICD. And at this point, we're left with a decision about what to do with the new device. We could either plan for no further devices, he's not dependent at this time for a pacing requirement. We could clear his infection and then implant a new ICD on the contralateral side, or we can do it in a sub-QICD. And we went with implanting a sub-QICD because the patient still had reduced elderly function, goals of care hadn't changed. This is the EKG at the time of hospitalization. 13 months later, patient unfortunately presents to an outside community hospital with shortness of breath and fatigue and is found to have complete heart block. And now we're left with a decision about what to do with pacing requirements for him. We do a leadless pacemaker. We implant the new transvenous pacemaker, the CRTP system, and use a sub-QICD in a hybrid approach. Or we can implant a new transvenous ICD, a CRTD system, and remove the sub-QICD. We eventually decided to do a right-sided CRTD system since his elderly function was still reduced and the SICD was turned off with plans for implantation later. Patient's doing well a week later, but unfortunately about a month later comes back with pirulonidrin at the incision site, now on his right-sided implant. We plan to implant and do a semi-permanent pacemaker, and now we're left with a decision about now what do we do with this device. He's had extractions bilaterally over the last year and a half, but he definitely needs pacing. So we could do the same thing, clear the infection, do a new implant on the left side, which was previously extracted from, or we can do a leadless pacemaker, which doesn't leave him with an ICD. So for patients with leadless pacemakers who need ICDs, there's like three silos that I like to think about. One is patients with infections, one is bridge devices, and one is patients getting transcatheter valve replacements. And I apologize, one of my colleagues did a much better job at doing the transcatheter valve replacement, so I'm gonna skip over some of the slides. Patients with infections, as Elisa did earlier, it can be used as bridge devices where you're waiting for the new implant and you allow for a prolonged course of antibiotics. But they can also be used in conjunction with extravascular ICDs, like sub-QICDs or EBICDs, to avoid any intravascular hardware to minimize the risk of repeat infection. There was a study in 2016 which looked at the feasibility of doing concomitant leadless pacemakers with sub-QICDs. It was done in animal model in two sheeps, and then right after that, the same group looked at three patients. One of them already had a leadless pacemaker in SICD, and two had leadless pacemakers underwent cardioversions, to look at how feasible it was. The study was really important because it pointed out a couple of drawbacks or pitfalls that you can fall into if you're trying to do this approach, and it was really elucidative for that approach. Since then, there's been multiple case reports. Most recently, there was a first of a dual-chamber pacemaker with a sub-QICD, which was published earlier this year in Heart Rhythm. What's important is the sub-QICD vector configuration is really important for the leadless pacemakers, and in this particular case, one out of the three was successful, and so it was implanted successfully, as seen by the X-rays on the right side. So for leadless pacemakers with ICDs that are extravascular, and particularly sub-QICDs, there's a couple of pitfalls or caveats. The location is very important because it can impact the way the SICD senses. The location of the lead for the SICD is also important, whether it's right or left of the sternum, because again, it can change the vector configuration. The effect of conductive communication that the leadless pacemakers use can maybe impact the SICD function, at least during interrogations. Pacing during VF may cause under-detection by the SICD, and certainly is the appropriate function maintained after an ICD shock for the leadless pacemakers. So it's really important for all leadless pacemakers being implanted in this configuration, whether done concomitantly or after the fact, to have all three vectors assessed. It's ideal to have two, if not three, be appropriate, and one certainly is necessary. And for patients being done concomitantly, it's important to be able to redeploy the leadless pacemaker if the configuration is not adequate, because a different location might have a very different R to T ratio, allowing for better SICD recognition. This is shown in the example from that study, where at baseline, all three vectors had appropriate sensing, but when you start pacing from the leadless pacemaker, the secondary vector is under-sensing, which improves when you start doing high-output pacing, and which brings up another point, making sure you interrogate these devices at multiple pacing thresholds to make sure that as time progresses, if the pacemaker has change in parameters, it does not impact the ICD. But it is a feasible option. The SICD lead location from left to right of the sternum can also play a big role. The image on the left shows it when it was on the left side of the chest, and subsequently, since it failed all vectors, it was re-implanted on the right of the sternum, and two out of three vectors were appropriate, and allowed for appropriate ICD function. Even though there is thoughts that conductive communication with the leadless pacemaker may be hampering the SICD or cause noise, there doesn't seem to be any impact, and certainly does not require deactivation of the SICD during interrogation. Of note, the AVID systems, because of the way their conductive communication is done, it may require some manipulation of the patches, both anteriorly and posteriorly, to get signal, especially during implantation, intraoperatively. In this paper, again, they looked at what would happen with leadless pacing during VF, and they did asynchronous pacing from the leadless pacemaker while induction was being performed. And thankfully, the sub-QICDs do not mistake these pacing artifacts, and can appropriately deliver charge ICD shocks. The leadless pacemaker also, as seen by the left side image, does not inappropriately understand, and will not pace while VF isn't. And certainly post-ICD shocks, both by external shocks or by the ICDs, sub-QICDs do not change electric parameters for the leadless pacemakers, making the function of the devices bilaterally okay after shocks. So just as a brief thing, because this is not technically out yet, the Boston Scientific Modular System is currently seeking approval from FTA. It is their sub-QICD, along with a single-chamber BVI pacemaker that will allow both command ATP and allow for pacing. Hopefully they're going to get approval towards the end of this year, and so this will expand our ability to provide for these patients when they should not have any transvenous systems. When we talk about bridge devices, we're really talking about patients from the extraction world who had infections, got extracted, and either they didn't have prior therapies or do no longer require ICD therapies and leadless pacemakers were a perfect scenario for those, or patients who do have therapy requirements but cannot get it right now because they are undergoing antibiotic therapy, have prolonged courses, have reduced renautomies, and need longer course of antibiotics, a verbal defibrillator with a leadless pacemaker makes the most sense in these cases. An ICD can certainly be re-implanted after the fact with a leadless pacemaker either being deactivated, set to backup, or at least being removed as in the case with the Amir system. If there's patients with device malfunction who are not candidate for extractions but have pacing requirements, as long as they don't need an ICD any longer, whether it's goal of care change or whether it's their LV function being improved, they can get leadless pacemakers. Patients who are heart failure patients with BiVaz or LVADs as destination therapy but need ICDs, if they have new pacing indications, a leadless pacemaker makes sense. Or if they've had recent infections, whether it's driveline infections or otherwise, to minimize risk of infectious burden, leadless pacemakers can be used as bridge therapy. Heart failure patients who are on the transplant list but not currently category one who need ICDs, a wearable defibrillator and a leadless pacemaker serves the function without risking increased infection. And then the category of infiltrative or inflammatory cardiomyopathy patients who are on high-dose steroid therapies after a recent diagnosis, have pacing requirements as long with, as with most sarcoid patients, a leadless pacemaker can be a good bridge too for the therapy. And then for transcatheter valve replacement patients, post-procedurally, it's really important because a lot of these patients may or may not, and I guess the jury's still out, require us to not do any transvalvular leads. And if that's the case, then leadless pacemakers with some sort of extravascular ICD is the only option. Sub-QICDs or EBICDs work for both in that scenario. And the real reason is to not try GL for the leads or not put leads further across these valves because they may have long-term impacts. But as previously suggested, the data is not out there, so we don't know what happens with these patients, and maybe putting an ICD across this valve is not the worst thing in the world. And this was data previously elucidated, so I'm not gonna go over it, but there is a 10.7% entrapped lead failure rate, up to seven months. So back to our case. We decided that we didn't want any further leads in the vascular system. He had already gone under his explantation of the CRTD system. We ended up implanting a microAV, checked all three vectors. The RNC ratio was appropriate. All three vectors were fine in configurations, and the patient left fine. The plan, actually, the patient has been doing well. He's been carefully monitored to make sure there isn't a change in his LV function, given the fact that he's 100% pacing and his initial EF was less than 50. And he seems to be doing well without any recurring infections or need for any further extraction procedures. All right, thank you. Thank you, Dr. Jain. Thank you. Our last speaker is Dr. Matthew Zipsy, who is going to be speaking to us about atrial leadless pacing. Okay, good afternoon, everyone. I'm your closer today, and I recognize I stand between you and perhaps a drink at the welcome reception or a walk along the waterfront, so we're gonna get right into it. I'm tasked with discussing atrial leadless in this case-based discussion. So my first case is a 58-year-old woman with a long history of surgeries for congenital AS and co-arct, and she's had three prior sternotomies and has most recently a redo mechanical AVR-MVR 20 years ago. She has heart failure, and in 1997, almost 30 years ago, was implanted with her first defibrillator. And since then, it's been really a failure of lead management. So that's her X-ray. She's got multiple redundant dual-coil ICD leads. In the last year, she's had innumerable ICD shocks for rapidly conducted atrial fibrillation, despite 400 daily of amiodarone. Her atrial lead doesn't work, doesn't capture or sense. Her underlying rhythm is sinus arrest, and she sees RV pacing. She feels terrible. She wants her defibrillator off. And in that context, she was referred and was on my schedule as a telehealth visit to establish care. So what in the world are we gonna do? Are we gonna, a reasonable case can be made to ablate her, but what are we going to ablate? Are we gonna do an AV node ablation? Are we going to do an AF ablation? And what are we gonna do with her device? Are we gonna add more leads to the heap that's in there already? You know, she's got LV dysfunction, she's RV pacing. Does she need an LV lead? Her atrial lead doesn't work either. Are we gonna extract everything and start over? Are we gonna do nothing? Are we gonna do something else? And I'll let you look one more time at that image. You know, that's almost a 30-year-old dual coil, you know, 11 French defibrillator lead. So this is a real mess. And yes, she's 58, but she's frail. And so, you know, it took a couple clinic visits to sort out what we're gonna do for her. She was interested in minimizing procedural risks. She was not interested in extraction. She wanted her defibrillator off, but wanted to understand more if she needs a defibrillator. So we made a plan for an AF ablation. I wanted to map her right atrium, understand what was wrong with her atrial lead because the impedance was normal. There was not noise on that lead. Sort out what we could or should do for her device, and then do a VSTEM to inform decision to turn her ICD off. So this is her baseline rhythm, RV pacing, sinus arrest, and actually retrograde conduction. I'll skip quickly through the ablation, but she had multiple inducible flutters. So we did PVI and the interoceptal mitral line shown there on the ICTI line. She was non-inducible. We mapped her right atrium. There's a few myocytes that remain. So here we are mapping actually the inferior limbus of the interatrial septum, and that's a retrograde conduction propagation displayed on a voltage map of her right atrium. And so ice was critical in this case, and we opted to place an atrial leadless pacemaker on the inferior limbus guided by ice in that voltage map. And with that, she had right bundle branch conduction with an HV of 44. This is the device release. This is her final fluoroscopy here. And this is her pre-procedure RV pacing, and there is atrial pacing with right bundle branch block conduction. The threshold is not normal. It was two and a half on her post-op day one. Her sensing is actually okay. It's 0.6, low impedance. So this may not be the end of the story for her, but for now, she feels well. She's off amiodarone. Over four months of follow-up, she hasn't had recurring AFib. And perhaps most importantly, she's happy that her tachytherapies are off, and there's a couple years of battery life left on her defibrillator, which is set to a backup pacing mode currently. You know, this case emphasizes, obviously that was a unique place to place an atrial leadless device, but even when approaching a standard case, I've found ice to be invaluable in these cases. You can see your anatomic target. You can see your approach, confirm tissue contact, confirm fixation, and obviously you can survey for a pericardial effusion. So I think ice is really helpful. A quick note on the difference of the atrial device versus the ventricular. It has an inner helix, which is electrically active. The outer helix, the bevel, is oriented in the opposite direction compared to the ventricular device, and that was done intentionally to reduce the risk of pericardial effusion and pericardial pinning, and Michael Alchami from Emory has made this point that the risks of perforation and dislodgement likely are related and inversely proportional. So by reducing the perforation risk, we likely take on some dislodgement risk with the atrial leadless device, and that was shown to some extent in the initial ID trial, which had 1.7% dislodgements acutely, but also about a 2% risk of late dislodgement, up to three months in the one-year follow-up study. So that sets us up for case number two of a 72-year-old with an atrial device that's dislodged, underwent a dual-chamber pacemaker for AV block in July of last year, and four months later had acute onset dyspnea, came to the ER, and was found to have embolization of the atrial leadless device. A retrieval was attempted, but limited by lack of reach from the dedicated retrieval catheter. Ultimately, a transvenous device was placed, and this device was left as it laid in the left PA. A month later, the patient is still having exertional dyspnea and has an oxygen requirement, and so in that context was referred to me in living in rural New Mexico, I contacted the PCP and had them repeat a CT to confirm the device hadn't moved from that imaging, confirm there's no surrounding thrombus around the device, and sort out whether there was a pulmonary infarction, which there was not. But other considerations include that this is a relatively long dwell time to take this out of the lung, compared to reported cases, I felt like there's some potential for adhesions, and some risk of pulmonary hemorrhage removing this. And of course, we can't use a dedicated retrieval sheath because of the lack of reach, and the patient has fresh transvenous leads. This is the patient's CT, which shows the Avera-AR device in the superior segmental branch of the left lower lobe. This is the 3D reconstruction, here you can see the device is dislodged and oriented in a backwards direction with the helix exposed. So this was a case where I actually approached IR, I felt like this is a good multidisciplinary case, I was interested in using this catheter, which is indicated for pulmonary embolectomy in the setting of acute PE, it's a highly trackable, flexible sheath, that's 24 French, it's the NRE retriever 24, it tracks over a wire, and you can see we were able to approach right up to the leadless device, in this case, over a stiff wire. We opted to use the tri-loop snare, you know, our testing sort of on the tabletop with a demo device, this tends to keep the device centered with respect to the sheath, more so than the gooseneck snare, and so we're able to snare the device, provide a little bit of counter traction with this flexible sheath, and ultimately retrieve it. So also the removal then is a little bit more controlled, most reports talk about using an agilis, snaring the device and just pulling it through the heart, and I think there is some risk, obviously, of snaring a tricuspid apparatus with the helix when you do it this way, so this was a nice solution, and we just did a PA gram to confirm no extravasation. So in follow-up, this patient had immediate resolution of dyspnea and chest pain, a resolution of his oxygen requirement, the transvenous system is functioning normally, we opted to leave the VR in place, given the leads were fresh. So in conclusion, atrial leadless pacing, with or without concomitant ventricular device is feasible and safe, for sinus, no dysfunction, ice, I think, is useful in these cases, and device dislodgements have been reported, but it is possible to retrieve these systems. Thank you for your attention. So unfortunately, that brings us to the end of our session, so thank you very much for your attention, and thank you to the amazing speakers and the cases that were presented today. If you have any pressing questions, I'm sure they'd be happy to answer them after the session. Thank you.

leadless pacing

congenital heart disease

tricuspid valve disease

lead extraction

ICD integration

pacemaker complications

HRS San Diego

procedural adaptations

infection risks

pacing technology