Thank you, and I think we will look forward to a wonderful session, and we will do the Q&As after all three of our excellent presenters, and we'll have plenty of time for that to begin. So, first speaker this afternoon is Pierre Lambiazzi, and he's coming to us from quite a long ways away across the pond from the U.K., and Pierre, we look forward to your talk. Thank you very much. So, I'd like to thank the faculty for inviting me. I was going to say to sunny San Diego, but I just got drenched outside, so I should have brought my umbrella from London. So, my remit's to look at a comparison really between transvenous, subcutaneous, and extravascular ICDs, choosing the right device for the right patient. I thought what I would do since most of the data is really comparing the subcutaneous versus transvenous systems to look at that data first, so that's our evidence base for which we make patient-informed decisions, and then move on to look at the additional option now we have for subcutaneous ICD with the modular leadless pacemaker approach, which expands this ability to actually undertake ATP and pacing, and then move on to extravascular ICD data with some comparisons, and then do an overall comparison of all three systems weighing up the pros and cons. So, as I'm sure you're aware, the main indications of subcutaneous ICD are for patients who do not have a class one indication for bradycardia pacing or anti-tachycardia pacing for monomorphic VT or CRT, so this is a population that do not need to have pacing, and there's been significant advances in subcutaneous ICD over the last, really, 15 to almost 20 years now with slimmer systems and also the availability of the SMARTPASS algorithm to avoid T-wave over-sensing, and now, of course, the addition of leadless pacing. And the first most important point with subcutaneous systems is that they are highly efficacious at DC cardioversion, the SICD has a 98% cardioversion efficacy for discrete episodes and 95% for storm episodes, and this is data now with five-year follow-up in the effortless registry. And the other issue, of course, which has been a major question with subcutaneous ICD is that what if the patient needs pacing, is there gonna be a significant proportion of patients that will need to transfer to a transvenous system, and we've shown with a number of studies now, some with over 1,000 patients, that the incidence of pacing for bradycardia or ATP is two per 100 patient years. So with the right patient selection, a very small proportion actually need backup pacing or ATP. And the best comparison, really, between subcutaneous and transvenous in a balanced way has been with the Pretorian trial. This randomized just over 400 patients to either form of therapy, as long as they didn't have slow VTs, less than 170 beats per minute, and also had the clear indications for a subcutaneous ICD without a brady indication. And just to look at this data more carefully, this is a population which was 80% secondary prevention population, 70% having ischemic cardiomyopathy, 30% non-ischemic cardiomyopathy, and a fair proportion of patients with diabetes and a mean age of 63 years. And the main find of this study was the primary composite endpoint of inappropriate shocks and complications related to the device and the device implantation. And you can see here there's a balance. There was equipoise in terms of the combined composite endpoint, with inappropriate shocks being slightly higher for the subcutaneous ICD in an era when dual zone programming was not used, and also smart pass filter was not available in the early phase of this trial. The device complications, there was a trend towards a higher burden of device complications as a transvenous ICD versus subcutaneous ICD. And actually, when this was broken down, looking specifically at what type of complications occurred, these were mainly lead-related complications due to the transvenous ICD, which met statistical significance. And this is the advantage of the subcutaneous system. It avoids any transvenous lead placement and the long-term effects of this. And this has been now brought out in the Pretorian XL trial, where the burden of complications is lower with the subcutaneous ICD. With the ATLAS trial, which looked specifically at complications related to the lead and device complications with subcutaneous versus transvenous ICD, there was a 90% reduction in lead-related complications with the subcutaneous ICD. So we know it's safe and effective in these patients, and you would avoid lead-related complications. The main issue has been, initially, this issue of inappropriate shock therapy, which, interestingly, with the transvenous ICD was more a problem with rapidly conducted atrial fibrillation, and with the subcutaneous was more an issue of T-wave oversensing. You'll see later that the inappropriate shock rates have dropped significantly over the past decade, and I'll show you that in comparison to the extravascular ICD. The important issue with SICD implantation is it has lower burden of surgical complications, and this has been borne out now in a large number of studies on meta-analysis. The other issue, of course, is appropriate therapy and ATP, the question about ATP availability. If you look at the subcutaneous versus transvenous ICD in the Praetorian trial, there was no difference in appropriate therapies delivered by the devices. This is quite an involved figure, but essentially 400 in each arm, and the main point to make is that there was 94% first shock efficacy with subcutaneous ICD, transvenous equivalent, 92%. ATP was efficacious 46% of the time in terms of terminating VT, but the most important thing really to be aware of is that the overall number of appropriate shocks was comparable between the two groups, despite the inability of the SICD to deliver ATP. So despite ATP being there, the burden of appropriate shocks was the same, and this is because the SICD delivers therapy later. Many VTs self-terminate. And the main issue of whether ATP really is an advantage is borne out by the APPRAISE-ATP trial, which is a randomized trial of transvenous ICDs programmed with ATP plus shock if a VT was more than 200 beats per minute for the first therapy being one round of ATP versus shock only as a first treatment, and there was a 28% relative risk reduction in freedom from shocks when ATP was available. Time to first shock was reduced with ATP being available, but there was no difference in all-cause mortality and no difference in all-cause shock or death. And indeed, actually, when you look at this population of patients who had ATP available, there was a higher burden of storm-related events in the ATP arm. So although the burden of the appropriate shocks was reduced, there were more VF storm events with ATP. So this is something to be aware of when considering ATP programming. Now the major advance with the subcutaneous ICD is now the ability to deliver a leadless pacemaker, which can essentially enable BRADI pacing and also ATP. And this has really transformed the system into essentially a modular approach where there's the option of adding a leadless system if necessary. This is examples from the preclinical study showing the efficacy of ATP in terms of terminating ventricular tachycardia. The device can communicate to the leadless pacemaker, and in the Modular ATP study just published in the New England Journal of Medicine, there was only a 2.5% complication rate related to the leadless system with maintenance of communication between the leadless pacemaker and the subcutaneous ICD and maintenance of pacing thresholds. And you can see here that ATP was delivered in 13 of the patients in the study. Success rate is 61% in terms of terminating VT, and there were no inappropriate episodes due to over-sensing of pacing by the subcutaneous ICD. So an efficacious option to terminate VT painlessly with ATP with the subcutaneous ICD if it's required. Now this really brings us to the issue. We've got an incredible amount of flexibility in how we actually manage our patients. If we have a patient who doesn't have a BRADI or ATP indication initially, one can implant a subcutaneous system. And if they develop a monomorphic VT and shocks, which is about 20% of the population in the Praetorian trial, then you can implant a leadless pacemaker to then deliver ATP later down the line. Or you could undertake a VT ablation to prevent further monomorphic VT. Or you could do both, do an ablation and then as a backup implant a leadless system. And so there's increased flexibility to deliver. The challenge is going to be cost efficacy in terms of delivering these options. And then, of course, now we have the extravascular ICD, which then offers an up-front option of delivering ATP in patients who may have monomorphic VT and an indication for an ICD. And the device consists of a lead tunneled onto the sternum to deliver ATP and transient backup pacing for a very short period of time, but it cannot deliver continuous pacing. The generator is implanted in the same site as the subcutaneous ICD and is a smaller Medtronic ICD generator. If we look at this population of patients, it actually isn't very different from the Praetorian trial. Slightly younger, 54 years old, primary prevention in 80% of the patients, and ejection fraction of 40%. And a high proportion, 80% again, with cardiomyopathy. So a nice comparison, a comparator, with the Praetorian trial. And the device maintains a very high efficacy of DC cardioversion at less than 30 joules of VF and a low complication rate with parity, really, with the subcutaneous ICD. And this is up to a year follow-up. There were some complications related to the device, system-related complications, mainly related to lead displacement in a small proportion of patients, 2.8%, sorry, 2.5%, and requiring either lead repositioning or lead removal. There was a very small, low instance of infection of only 0.6%, which is very reassuring with implanting a lead in the retrosternal space. The main issue has been inappropriate shock therapy, which was at essentially 10%, 9.8% at one year, and rising to 18% at three years during the long-term follow-up study just published. Now, interestingly, this isn't very different from the subcutaneous ICD initial experience. When you look at one year, it was 8.7%, and at five years and effortless, it was 17%. And this is because of this inability of the lack of dual-zone programming initially and T-wave over-sensing. The main issue with this, the EVICD, has been initially P-wave over-sensing and a lack of an algorithm to avoid inappropriate shock therapy in the early phase, which is now being addressed. And this really shows how the inappropriate shock rate has declined over the years with the subcutaneous ICD, with the introduction of the smart pulse filter, and now down to a 1.8% one-year rate of inappropriate shock treatment. And this, if you look at the extravascular ICD, this is where we are with the extravascular ICD at the moment, at 10% inappropriate shock therapy rate. So there's a learning curve which is now going on to minimize this and bring it down to the low levels we see with transvenous ICD systems. And thank you to Francis Murgatroyd, who's been one of the pioneers of the extravascular ICD, really for this slide, because this is a slide I've adapted from his talk. I have a slightly different view. But essentially, we can divide the devices between transvenous ICD and extravascular in terms of implant functionality and long-term outcomes. And essentially, ease of implantation, we're all familiar with how to put in a transvenous or subcut ICD. It's a relatively straightforward procedure. Obviously, you need a GA with the subcut. You need a GA with the extravascular ICD. So I'm understanding now that some centers are already implanting this on the local anesthetic. Obviously, there's a learning curve that's required for implantation of the extravascular ICD, with a surgeon being available in the initial phase of implantation. Extravascular ICD is contraindicated if you have a stenotomy. Prior stenotomy isn't really an issue with subcut ICD. You just have to be a bit careful with the sternal wires. Transvenous ICD, obviously, not an issue. Risks with transvenous ICD mainly relate to lead placement and entering the vasculature. Extravascular ICD is still relatively early days in terms of what these risks are. But fortunately, most of the risks have been related to lead displacement, not related to RV perforation or infection, which is very reassuring. Post-shock pacing available really mainly for transvenous and extravascular ICD with some backup pacing for subcut in the first 30 seconds with bradycardia. In this slide, really, we can adapt now. Because if you have bradycardia asystole, and you have a leadless system, then actually you can overcome that problem. And similarly, you can overcome that problem with subcut ICD with ATP, giving an advantage now that if you want it, you can use ATP in these subcutaneous ICD patients. Finally, comfort really is equivalent across these systems. Most patients tolerate a subcut ICD very well. So you need a very slim-framed patient, so that tends to be an issue. And inappropriate shock rates now are more an issue with extravascular ICD, as I've highlighted. And the battery in the SICD is only seven years, with these transvenous devices being used, or up to 12 to 14 years, depending on how much the device is used for pacing, certainly with transvenous or number of shocks delivered. So really, looking across these, the extravascular ICD, in my mind, really is, at this stage, certainly will be a first-line consideration for patients who are having monomorphic VT, and you want to avoid the vasculature. Younger patients, perhaps people who do a lot of sport, and are likely to suffer long-term lead complications, as opposed to a patient in their late 60s and 70s, where a transvenous lead is less of an issue. But to be honest with you, any transvenous lead carries the risk of infection, the risk of complications with extraction, and a mortality in a primary prevention device, which can be completely avoided if you don't need to put in a transvenous lead. So SICD is now becoming established in primary and second prevention patients, and increasing age and subgroup populations, which it's suitable for. There are fewer lead and procedure-related complications, versus this transvenous ICD. The moderate approach really gives us greater flexibility and confidence in SICD prescription, and the need to convert to a transvenous system isn't really necessary, because we can put in a leadless pacemaker. Extravascular ICD is an emerging option to avoid transvenous systems, but it's early days. We don't know what the long-term performance is. We only have really follow-up for five years. We've only implanted 2,000 of these devices, and we still have to wait and see how this will manifest over the next decade to 15 years with this system. But certainly smaller body habitus patients needing first line ATP should be a strong consideration at this stage for the extravascular ICD. Thank you for your attention. Perfect. We will go on to our next speaker, which is Dr. Rhea Pimentel from University of Kansas, Rock Chalk Jayhawk, my alma mater. Go KU. That's right, your alma mater. She's gonna speak to us about devices in patients with complete heart block. Okay, I just wanna take a second to say thank you to Heart Rhythm Society for allowing me to speak today. When I got this topic, I thought to myself, what is the patient that most keeps me up in terms of what kind of device to put in? So this is gonna be a case-based presentation, and I don't think that there's a completely right answer, which may make this harder or easier, but let's talk about this patient. So these are my disclosures. Okay, so this is a 19-year-old female who presented in my office a couple years ago now after recently discovered complete heart block. She's a competitive swimmer, has a scholarship to a Division III team. Her specialty is butterfly. As part of her pre-participation physical for the NCAA, she was noted to have a heart rate of 40. So a subsequent 12 lead EKG showed complete heart block with a very narrow junctional escape. She underwent a 48-hour Holter monitor that showed a sinus rhythm with complete heart block the whole time. Max rate of 65, mean of 52, no ventricular arrhythmias. She gets an echo, her heart function is completely normal, no wall motion abnormalities, no valve disease. She's seen by a pediatric electrophysiologist and undergoes a genetic workup. Primarily for maternal autoantibodies and it was completely negative. So it's really unclear when she developed complete heart block, but she has obviously been swimming 17 years in her life and gotten to a fairly high level without any significant symptoms. So this is her EKG just to verify, you see complete heart block with a junctional escape that is relatively narrow. This heart rate here is 49 beats a minute. So she's actually seen at an outside hospital to begin with where she's swimming and she undergoes a successful dual chamber pacer. Six months later, her atrial lead impedance increases fairly quickly and no capture, suggestive of lead fracture. So the decision was made at that time to turn off her atrial lead and she finished her swimming season at VVI 40. But just prior to the start of her sophomore swim season, her RV lead starts to show evidence of increasing LV lead impedance. Capture threshold is elevated. So since she lives in Kansas City, or her parents live in Kansas City, she was referred to me for lead extraction and re-implantation. So I think I saw her the Monday of Thanksgiving week with the question of, can we get this fixed and put another device in me? Or do we put another device in me? So I took one look at her and I said, gosh, this is a 19-year-old female who is in heart block, but we have a lot of considerations. Now in talking to the patient, she tells me, I had a lot more energy while I was swimming with a functional device. And I recorded some of my best times during that time. Not all of them, but some of them. She knows that she is not an Olympic caliber swimmer, but she would love to finish out her college career if possible. She has a scholarship. But on the other hand, she knows that if she needs to quit swimming, because for best treatment, long term, she will do that. So when I looked at her, I thought to myself, well, do we really need to put a pacemaker in her? She's asymptomatic. She has congenital heart block. Her QRS duration is fairly narrow. She has no ventricular arrhythmias, at least by a 24-hour Holter monitor. The symptom improvement she describes is marginally best, because she's still obviously swimming at a very high level. And I have to consider things like long-term lead management. How long are these leads gonna last? How long will the battery last? We're talking about a 19-year-old kid who's got, presumably, 60 years of life left. And then, of course, pacing-related complications. Lead-related, particularly tricuspid regurgitation, and then, of course, pacing-induced cardiomyopathy. So these are my options in my head for device implantation. And I wish I had made this into an audience response system, but maybe you guys can just raise your hand if you would not put a device in this patient. Maybe an ILR, okay, great. How about a transvenous dual-chamber conduction system pacer? Cuz we don't put any regular pacers in anymore, okay? What about a Bi-V? Okay, a leadless pacer with atrial tracking capabilities, okay? And then what if you just put a leadless pacer in, set it VBI 30, like a V pacer, and then switched her over to a transvenous conduction system pacer in the future? That would be an option too, okay. Okay, so I had to read about congenital complete heart block cuz I'm an adult electrophysiologist. But what I found is that the incidence is about 1 in 15,000. Typically autoimmune mediated, you think about the antilupus, antiro antibodies. We know that the patients who develop AV block after birth has a much more benign process. But when you discover patients with heart block, young patients with heart block, they oftentimes have very nonspecific symptoms. Poor growth, fatigue, sleep disturbance, nightmares. Some are completely asymptomatic, which I really believe that this patient was before her diagnosis. Sometimes this can be a harbinger of long-term T3, brugada, rheumatic disease, some sort of metabolic or infiltrative process. So when I looked at the initial data, I noticed that a lot of times the thought process was if patients were asymptomatic and their LV function was normal with relatively robust heart rates, 55, and without pauses or wide QRS complex, that maybe they did not urgently need a pacemaker. And I will call your attention to her mean heart rate was 52 beats per minute, no pauses. This is a 2021 expert consensus statement from our pediatric colleagues. And I will call your attention to the 2A indication here. Pacing is reasonable for asymptomatic congenital complete heart block after the first year of life when the V rates are less than 50 or there's a prolonged pause. So she doesn't really make that. She's more in the 2B category, congenital complete heart block in asymptomatic adolescents with acceptable ventricular rate, narrow QRS normal function. So the problem is is that these patients with asymptomatic congenital complete heart block have a high incidence of unpredictable syncopal attacks, the so-called Stokes-Adams attack, where they either have bradycardia-induced torsade or their escape rate becomes unreliable, particularly as they get older. And some of the studies will show that the mortality rate in these patients that are non-PACE will go up to 8%. We know in general that as we get older, our heart rates decrease, and so it can lead to progressive chronotropic incompetence even in this patient population. And chronic AV dyssynchrony can lead to LV dilatation and cardiomyopathy in itself, as well as acquired mitral regurgitation. So there are two types of cardiomyopathy that can occur with congenital complete heart block. One is just related to that AV dyssynchrony itself. So pacing those patients earlier, actually they have a very good prognosis of recovering their LV function. When you pace these patients, they are, you know, so you're darned if you do and you're darned if you don't, right? So if you pace them, you also have an increased risk of pacing-induced cardiomyopathy up to 32%, and the median time to this to occur was about 4.7 years. And so we have to consider that as well as the lead longevity. You know, these are young patients that are very active, so their lead longevity is low, 76% five-year survival rate in one study with a lead failure rate of 23%. And if we're putting these devices in small children, the rate of occlusion or significant stenosis in our transvenous leads is relatively higher, obviously. So younger implant patients typically do worse long-term. In addition, many of us in the extraction world, too, as well as any person that implants transvenous devices realize that tricuspid regurgitation is something that we're seeing, we're recognizing more and more associated with leads placed across the tricuspid valve. So what other options do we have? Well, we have the leadless pacing options to prevent tricuspid regurgitation. There's still that risk of RV pacing-induced cardiomyopathy, although this is a study that I pulled out from 2021 that looked at the incidence of pacing-induced cardiomyopathy with leadless pacers and found it to be significantly lower, probably because of the septal placement and the lack of tricuspid regurgitation. So based on all of that, I chose a single-chamber VDD leadless pacemaker. And so this was implanted I think the day before Thanksgiving in 2021. She went home the next day. She resumed her swim career about a week later after her groins had healed up. We all know this already, but there are two FDA-approved devices out there for leadless pacing, the Medtronic device, which comes in two flavors, the VR as well as the AV, which has the tracking capabilities. And then there is the leadless AVR made by Abbott, which also has a ventricular lead for sensing and pacing as well as an atrial lead. So this device will obviously provide atrial pacing. This one does not. Fortunately in our patient, we did not need atrial pacing. The way that the Medtronic device does atrial tracking capabilities is by using their accelerometer, which identifies an A4 signal, which is commensurate with atrial systole. And so the device will pick up that A4 signal and use it to pace the ventricle based on that. This can be a problem in younger patients when their atrial rate is elevated because you could see that there might be an issue with A3 and A4 melding together. And then we have some difficulties with trying to track appropriately. In this particular patient, actually she did fairly well. She came back a couple times for reprogrammings to better assess that A4 signal and track appropriately. And as far as I know, she is completing her senior year right now in swimming. And then we have to figure out what to do with her afterwards. So in the four years that I made this decision, I was thinking about what I would do. And I think now I would consider putting a retrievable leadless pacemaker in with plans for removal and reimplantation of a conduction system device in the future. Again, there's no good answers for this. I mean, I think we all know that the Holy, well, we all feel that the Holy Grail would be a conduction system leadless pacemaker, which would hopefully solve that problem of pacing-induced cardiomyopathy. But there is, the one device has a chronic retrieval mechanism, an active fixation helix that can be retracted with relatively good retrieval data, up to six years here in this study. So that's all I have for you today. Thank you. Mm-hmm. Thank you. Thank you so much. And rounding it out, going from furthest distance to closest distance, from UCSD, we have Dr. Anne-Sophie Lecherich-Roberge, and she's gonna talk to us about patients with sick sinus syndrome and pacemaker needs. Right, I just wanna thank everybody and the faculty for inviting me to speak. This is a great opportunity, and let's get started. So when I was given this topic, I thought, this is fantastic. This is exactly how I've been feeling since I started as an attending less than a year ago. This used to be easy, and not so long ago. Even when I started my fellowship just two years ago, we didn't have as many options as we have today. So I had a lot of thoughts about the fact that it's becoming much harder to make the right decision. It seems like we had less choices with everything in EP. This was me as a fellow using RF to do all my PVIs, and now this is me as an attending and here at HRS learning about all the new technologies that are coming out, it seems like, every month. Oh wow, it's still looking. I said, I told myself, what is going on with EP? Right, we used to have only RF, and now we have a flower to a blade. We used to do this in four hours, now we do this in 40 minutes. We can also add a watchman if we want. So we have all these new options, and same things with devices. And I even talked to my senior colleagues about this so many times that for many years, the only options were transvenous leads. And now we started to implant the micra, now a few years ago, and now we have options to do dual chamber leadless spacing, which started during my fellowship. And of course, as we already mentioned, there's so much more to come with conduction system leadless spacing. And I thought to myself, you know, with all this great power that we have comes really great responsibility. Because we have all this new technology, we have all these new skills, doesn't mean that we need to use it every time, probably not. And we need to continue to make the best choices and the best decisions for our patients, and that requires a lot more discussion now because we have all these options that are very reasonable. So it's really not always that simple. So we're gonna talk about a recent case that was really just about a month ago. So this was a 65-year-old male with a history of hypertension. He was currently being worked up for renal cell carcinoma, daily runner, runs about a 5K every day, and came into the emergency room with presyncope while driving, had to pull over, was driving his son to college, very concerned. His Apple Watch at the time detected a heart rate in the 20s, and in the ER, he was noted to be in sinus bradycardia and was having symptoms while walking around in the ER and while his heart rate dropping into the 20s. Baseline heart rate was in the mid-40s. Remember, he's an athlete, has been an athlete for many years. EF is 50%. So options, many. Do we do a dual-chamber leadless device, a single-chamber atrial leadless device, a standard dual-chamber pacemaker, or left bundle area pacing? Some would say many of these options are very reasonable. So I always have in my mind the easy leadless decision and a not-so-easy leadless decision. So who's the ideal leadless pacemaker patient? Of course, and I always categorize them in my mind just this way, so in terms of vascular, of course, if you have limited access, occlusion, dialysis patients, both for access and for, of course, infection risk, makes sense. Specifically in regards to infection, of course, renal disease, as we already mentioned, diabetes, previous CID infection, immunocompromised patient, history of bacteremia, history of intravenous drug use. And then arrhythmia-specific, transient AV block or low pacing requirement, makes sense. And then other things, right, now cosmetic. It really is something that patients care about, now that we have this option. And then occupation-specific activities, like our patient who's an athlete and like our previous patient who was a young swimmer. And then extremes of ages, the very old, the very young. And then tricuspid valve dysfunction is another one that we're talking about more and more. So these are kind of the easy patients where I don't hesitate too much. I'm gonna do leadless pacing. Not so easy. So a few cases where I have to think about it twice before making a decision and I have to talk to the patient about what we're gonna do more extensively. The 90-year-old who's robust with borderline EF, sinus bradycardia, transient AV block. Few options that would be reasonable here. Although 90, some would say should go leadless, but maybe not. The 60-year-old athlete, similar to our case, with sinus bradycardia again, and no current evidence of AV block. But we know that in the future, a lot of these patients will go on to develop AV block. So what do you do? Again, atrial leadless, and then go on to add the ventricular leadless later. Do dual chamber leadless right away. Not so easy. And then the 40-year-old with complete AV block, sinus bradycardia, and an EF of 55%. Right, conduction system pacing. Again, that's the first thing that comes to mind, but dual chamber leadless, maybe not a bad option either. So of course, in 2023, we had a great study that showed very good success with the dual chamber leadless pacemaker with the AVERE. It was prospective, multicenter, single-group study, and the success of implant was very high at 98.3%. And the AV synchrony was excellent. 97.3% of the patients achieved AV synchrony. But beyond the success of implant, now because we have a new patient, now because we have all these options, I think it's very important to discuss complications related to both leadless pacing and transvenous device with our patients. And these are all things that I discussed with this patient that we're gonna come to a conclusion soon. So in terms of complication, I think it's important to look at the acute complication versus the chronic complication. There was a little bit more in the studies acute complications with leadless pacemakers versus chronic pacemakers. But again, overall, very safe. So in this study, all-cause mortality in hospital and the mostly less pacemaker population was higher, like we already mentioned, than the traditional single chamber transvenous device. And there was a higher inpatient morbidity signified by higher risk of death. And morbidity signified by higher incidence of blood transfusion, cardiac, vascular, venous thromboembolism, and device-related complications in the leadless device. And in terms of the transvenous device, there was a little bit more, of course, pulmonary complications and need for device revision as an inpatient. Things that we think about in the acute setting. I think there are patient characteristics that are associated with our most fear complications with the leadless device given our large sheath. And things like advanced age, COPD, female sex, and low body mass index are things to think about when we are trying to decide leads versus no leads. And then there's also procedural characteristics. Multiple deployments, we know that the risk of perforation increases with multiple deployments and multiple recaptures. And of course, it's quite a big learning curve when starting to implant these devices. And some centers do a lot, some centers do not so many. So that's also something to consider and to talk to our patients about. And this was the two-year outcomes of leadless versus transvenous single chamber, this is single chamber, but still, ventricular pacemaker. And this was in high-risk patients. But the benefits of leadless pacing was present in the chronic phase, of course. And the big thing here is the risk of infection that is so much lower, right, less than 0.2%. One thing that we don't talk about a lot, but I think is very important, is quality of life. So there was a large study that was done that looked at improvement in health-related quality of life with leadless pacing. And there was two studies that also compared quality of life between leadless pacemakers and transvenous pacemakers. And turns out that leadless pacing was superior in terms of physical and mental quality of life after leadless pacemaker implantation. So something to consider also. And of course, I'm an extractor, so extraction consideration, that is always on my mind. And this is me and my mentor, Dr. Green, extracting a patient. And of course, what I see when I meet these new patients who need pacemakers, I think about this, right, the disaster chest x-ray with so many leads when everything needs to come out. And we see this, infection, pocket infection. And then we need to do this, and we need to use these crazy tools. So something that I always think about and something that I also mention to my patients now when we're having this very honest discussion about what type of device is best for them. The other extraction consideration, and we already mentioned this, is the fact that now there is an option to retrieve some of the leadless devices. So of course, and we looked at the excellent trend of the AVERE in terms of retrievability over time. So that is also something I consider when I try to make this decision. So final details to consider. Of course, there's been a little bit of concern in terms of battery longevity with the dual chamber leadless pacing. The AV synchrony is excellent, not perfect. And then remote monitoring is the other thing that we haven't mentioned with the AVERE, which is about to come out, but not quite yet. So coming back to our patients, and now we have all of these details in mind in order to make a good decision. So again, 65-year-old, overall fairly healthy, daily runner, presyncope, and EF of 50%. So I thought there's probably two reasonable options for this patient. Either transvenous dual chamber pacemaker with left bundle pacing. Although he does not have complete heart block right now, his EF is 50%. If he goes on to develop complete heart block, would not be unreasonable to already have a left bundle lead in place, versus a single, versus dual chamber leadless AVERE. And we offered both options to the patient, and he chose to go with the dual chamber leadless pacemaker. So that's what we did, and I think probably the right decision in this patient. And that's it. This is my amazing team at UCSD. Thank you so much to all our speakers. I'm gonna go through a couple questions that came in, and people feel free to submit over the QR code, or we have mics in the room as well. So the first question, Faria, is, in your case, did you extract the transvenous leads, the plans for that in the future, and then also when the micro battery runs down, what's your future plans? So I'll just talk really loud. But yes, I did extract the device. Sorry, I didn't put it in my slides, but I extracted the leads, and if you can imagine, the leads were about a year old, so not terribly difficult, and no obvious fracture when I took it out. In terms of long-term management, I could say that I'll be retired by the time she needs a new generator, so it won't be an issue. She lives in Kentucky now, because that's where she went to school and so forth, so I don't see her electrophysiologist here in the audience today, but it's a micro, so I have not extracted many micros. I would assume that it would be fairly difficult just because those tines really scar in to the trabeculae as opposed to the EVAIR devices. So likely, if everything stays the same and she feels fine and we don't have a leadless conduction system pacer available, I don't know, I think, I would not extract the micro for sure. I would probably add a dual chamber conduction system pacer. I don't think there's any right answer here, so that's why I sort of brought this case up, because I'm just interested to see if anybody else had a visceral reaction one way or the other. No, I think that's great thoughts and great points, and yeah, and it's also exciting to think about, because who knows what we'll have options in the future. It's hard to kind of predict that now, but yes, I agree. And then there was a question just for all of us and the faculty and the panel, just people's different thoughts and viewpoints on taking age into consideration for leadless or not and how we all weigh that choice. Pierre, I'll start with you. Sure, I mean, I think with age, I mean, a lot of this relates, I think, to frailty and the fact that most of the complications from pacing arise from pocket-related issues. So if you have thin, frail, elderly patients, then I would definitely opt for a leadless system over a transvenous system. I think that's the main drive of my decision-making. Older patients who are diabetic, again, would be the same issue. So any significant risk of infection, I'll push much more for a leadless system. Anthony? Yeah, I think I would agree. For sure, the risk of infection, that's one of the biggest consideration. Age as well, but I do have to say that we've moved, at least at our institution, we've moved to also considering it for younger patients, like my patients, who are very active and would really rather not have a pocket and have a device underneath the skin. So we've moved towards, we're a little bit more liberal now in terms of offering it to people that are closer to middle age, I would say. Yeah, I completely agree. I think there is a role for these leadless devices in younger patients. I mean, if you look at the battery life, especially if the patient is not using it 100% of the time, you have upwards of 15 years with some of these leads. And the less times you have to intervene on a patient, I think, the better. Can I ask, actually, regarding programmability with the leadless system and with the AV system. So you've got quite a young, fit athlete. You may want to optimize AV delays, optimize their efficiency in terms of exercise. Do you have any issues with leadless in these younger patients, where you may want to actually optimize AV timing better for performance? I haven't had too many complaints, to be quite honest. And I would say that with the dual chamber of air, that really offers you that ability. So yes, to be able to do that often with even different pacing modalities, once we've got AI with VBI backup, that's also been kind of a game changer. There's a lot of really cool ways to do those programming of those devices as well. So, yeah. With a lead-less system, what is the risk when we talked about pacing cardiomyopathy? How often do you think of that? Do we have a lot of data showing that these patients could have significant pacing cardiomyopathy? The second question, and I know somebody mentioned this, when I'm thinking that through for my patient, how much evidence do we have with regards to that? And then the second thing was, if you have a patient that comes in with severe thrombocytopenia, you know, leukemia, maybe platelets in the 20,000s, 30,000s, what would you do differently? Would you want to do lead-less in this patient or severe coagulopathy? How do you approach these patients? And then the third question I wanted to ask is, with reference to implanting a lead-less, I don't know, what is your experience with ice or no ice? Does it give you any benefit, any advantage? I've seen some operators, they want to see exactly where things are in ultrasound, and I've seen people quickly use flora and get out of the room pretty fast and get it done. So those are my three questions. Those are great questions. And I think your talk touched a little bit about the patient-induced cardiomyopathy with lead-less. I think we're going to have to do, you know, there will be a lot more time, we'll tell, in the research and the data that comes out. There has been a little bit of a signal, especially in the study you mentioned, but that there may be not as high of a prevalence of patient-induced cardiomyopathy with lead-less, and a thought to that is that, you know, the devices are primarily put on the septum, and maybe what's going on there. So not involvement of the valve, but I think we're, you know, still kind of younger in where we're going to kind of follow these patients over time to really get a better understanding of that. I agree. It still happens. I do have some patients out there who had a lead-less V-pacer put in at one point, develops cardiomyopathy, we turn the device off, we put a Bi-V in or a conduction system pacing lead in or device in. So it happens. I don't want to say it doesn't happen, and certainly a consideration, especially if their EF is lower and things like that, and they're pacing all the time as opposed to occasionally. So I can't remember the rest of your questions. I'm sorry. I have a very short attention span. Oh, the ice. The second one was severe thrombocytopenia coagulopathy. How do you approach those patients? I just give them a transfusion and then go for it. For me, it's still less risky to do a lead-less versus a transvenous, personally. And then I don't use ice at all. I think for my first atrial lead-less, I insisted on putting an ice up, but it didn't really significantly help me. And so what I do do if I'm unsure is we always will do an appendogram for the atrium to show the appendage with contrast. And then if you're concerned as to where you are on the ventricle, you can also shoot some dye there to make sure you're up against the septum. I'll say that I get pretty nervous. When the EF is not completely normal and they're going to need pacing, I'm pretty quick to put in left bundle instead of lead-less. It does make me nervous. I think we've seen it. I mean, obviously, my very short career, but I've seen it already. So I'm pretty quick to go to left bundle or bivy or whatever is needed. I do use ice. I don't know if I will forever, but, yeah, I think it probably depends. But for me, I find it really helpful for the appendage. I would say that whenever the anatomy is not convincingly normal, if something doesn't feel right, I have a relatively low threshold to throw up an ice catheter just to understand what the anatomy is. But I find even with lead-less devices, it's unusual to need to do that. Thank you. Excellent cases and excellent discussion so far. I have an interesting case of my own colleague who is a general surgeon who has myotonic dystrophy, and his brother already had a pacemaker. So he's in his 50s, very active guy, bikes almost 200 miles every week and almost 2,000 miles-plus in a year, but not a bodybuilder, luckily. So when do you think I should put a pacemaker? His QRS is 105 milliseconds. PR is still under 200 milliseconds. And should I wait or should I go ahead and do it? And then second question is should I go ahead and do an ICD? But obviously I'll have to do a transvenous ICD because EVICD, sub-QICD will not do the trick because he will need a pacing in the long term. So what is your take on this? Did you get a halter on him by any chance? That's a good point, Dr. Pimentel. Actually, I just ordered it. I haven't had the results yet. So he's yet to do the halter. I can answer that. If the halter doesn't show any AV block, then I'd just measure an HV interval on him. His HV is more than 70. He's got a high probability of getting complete heart block, and then I would implant a pacemaker. We can have a discussion about what pacemaker you want to put in. You wouldn't necessarily implant an ICD, first-line inpatient with myotonic dystrophy, only if he's got significant LV dysfunction or you see, for example, you do an MRI and you see a lot of fibrosis and you may then be prone to get re-entry in VT or bundle branch re-entry. You could consider doing an EP study for inducible bundle branch re-entry in VT, and then you would consider putting in an ICD. But I would measure the HV first, do your EP study, look for bundle branch re-entry, and then you can make a decision. And I'll hand over to my leadless colleagues to make a decision about the device that they would put in. I just had a similar case of a young patient with myotonic dystrophy, and I brought him in for an EP study. That's exactly what I did. Measured the HV. It turns out it was actually very long. And I also did a V-STEM. Didn't have anything inducible, so I just put in a transvenous device. QRS and PR interval cross a limit. You need the HV to... Yeah. If the HV is more than 17... So go ahead and do it right away. Okay. Let SAS, about 30 years ago, 20 years ago, did a study that showed a high incidence of AV block. Subsequent larger series have shown the same thing. Especially if he has any symptoms at all, like dizziness and just so forth. Yep. Great. I do think these cases highlight the situation of be careful what you ask for because you just might get it. Exactly. I'm old enough that when I started my career, we were just starting to do CRT. And transvenous ICDs weren't even formally approved with a coverage determination by CMS. And as the technology has exploded, it's definitely increased both the range of options we have for our patients, but also the complexity of making those decisions. And these conversations in clinic, to talk through the shared decision making of the options with our patients is only becoming more and more challenging. Exactly. Yep. Totally. And just one last question from online regarding our experiences with leadless and percutaneous tricuspid valves like Evoque, the future valves coming out that are frail and not surgical candidates. And I will say that, you know, in my center I'm lucky that our structural guys and our valve guys were all collaborate together. Some are my surgeons who also do the extractions. And we've had good success using leadless devices, often in combination with extracting transvenous leads, putting in a leadless just to kind of get, to bulk any leads across the valve. Some of the valves have a larger profile, so you do need to look at the RV size. The Evoque is a little bit longer than the Micro, so some of the, you know, very, very smaller women, that may be a better choice, but you do need to kind of look at that, look at the valve footprint. But overall I think leadless is something that's going to come into play as we start to see more and more of these tricuspid percutaneous valves going in. I don't know if anybody else on the panel would chime in on that subject. All I know about tricuspid valve replacement is when I was a registrar, the consultant, he would sew the ring of the AV, of the tricuspid valve replacement, into the wall with a lead going along the side of the tricuspid valve, which I always thought was completely insane, but that's what they used to do. So I'm glad that there are leadless systems that can go through the valve now, too. At least you can extract them and replace them. Yeah, I think optimally if you have a good relationship with your structural colleagues, that will go a long way for the patients. I have put in leadless devices through some of these tricuspid repairs slash replacements. Definitely not FDA approved to do those kind of things. If you're very safe, careful, I don't know, have a surgeon there at the same time saying, don't do that, don't do that. But it's been fine, it's been fine. It can be done. I would also add that it's only been in the last few years that I've gone out of my way to attend our heart team conference, which has been mainly for the more complex decision making around does this patient go to bypass or PCI or should this patient get a surgical aortic valve or a TAVR. But bringing these conversations for wider input because I don't know if this has created the same situations for you, but the Monday morning quarterbacking that goes on after one particular decision gets made is sometimes painful. And when that can be moved to an environment where you can achieve consensus, we're finding that that's actually, in terms of diplomacy, making the road a bit smoother for us. Great. I'd like to thank all the speakers and I think we will conclude our session. But it was excellent, great talks, and I think it's fun. Devices are wonderful and fun and the decision making is a great part of it. Yep.

implantable cardiac devices

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leadless pacemaker

patient-centered treatment

congenital complete heart block

sick sinus syndrome

heart team conferences