Good morning, everybody. Welcome to this session. This session we will be talking about defining the success of AFib ablation, what should it be and what is important. Just a couple reminders, make sure that you are downloading the QR code that was up there so that you can participate in the QA session with us today through your app. Make sure you're signed in. So our first speaker of the day is Jonathan Pacini. He's going to be talking about determining the success of AFib ablation time to recurrence versus AFib ablation. Welcome. Well, thank you for the opportunity to be here. It is an honor, Professor Calkins and Professor Hahn, and it's so good to see many colleagues and friends in the audience. These are my disclosures. I'm not sure that's very readable, but I should have a more readable set here. So my task this morning is to talk about determining the success of AFib ablation and I'll be talking about a lot of things, but also focusing on the binary choice of time to recurrence versus AF burden. So these are my abridged disclosures. It's just important to recognize that I received grant funding from many organizations that manufacture equipment for catheter ablation. So I think in medicine, as a physician, I'm probably 100 times as guilty as everyone else. I talk too much and I don't listen enough. So listening's really important. So I wanna give credit to Brian Zenger and Ben Steinberg, who conducted a survey to understand from patients what matters. What do patients think success after AFib ablation is and what's the top priority? And by and large, patients, and we're lucky that we'll be able to hear from some today, express in general that their goal is to decrease the frequency or amount of atrial fibrillation that you experience. And if you ask them, say, can you drill down on that a little bit, what does that mean? You can see here that many would consider success after ablation may include having quite a bit of atrial fibrillation, but if it's less than they're having before, they view that as a win or a success. And so we often have these talks in clinic, right? A patient says, well, what are the outcomes? What is the success? And what we've traditionally had to deal with, right, is time to recurrence. So here is work I'm sure many of you are familiar with from Professor Jason Andrade, looking at the CIRCA Dose Study, which compared basically three different methods of ablation for atrial fibrillation. But that doesn't matter. What we're interested in here are the results or outcomes from the study. And you can see here that at 12 months, approximately half of the patients had recurrent atrial fibrillation. But if you ask a slightly different question, thinking back to the information and the guidance that the patients gave us, their number one goal is decreasing the amount of frequency that they have. And you look at the AF burden, which is the total time that the patients are spending in atrial fibrillation, what you see actually is that there's about a 99% reduction in the amount of atrial fibrillation that they experienced. So, you know, let's just throw medicine out the window and just, you know, common sense, which of these is a better communication of what the procedure does? Is it half the people are gonna have a recurrence at one year? Or is it much more informative to know that we've decreased the amount of atrial fibrillation someone's had by 98 to 99%. So I love sports analogies. If you work with me, you'd probably be sick and tired of them. But you know, this is what time to occurrence looks like. You know, it's not a very good play. It's not very pretty. Yet what actually happened was that the thing we're interested in getting rid of was gone for 99% of the time. And so I think that is a success. If we think about a-fib burden, this is not the topic of my talk, but it's just important to understand that we have a lot of different ways to measure a-fib burden. And the type of a-fib that someone has is, in some ways is an estimate for a-fib burden, right? It's either self-terminating or it's persistent. Some people like to talk about the longest duration of atrial fibrillation, which is yet again, another measure of a-fib burden. And then there's the purest form of a-fib burden, which is exactly how much someone's time is spending in a-fib. So why is it important? I think we can all agree that it helps communicate the results of the procedures a little bit easier, but why is it actually important? What's the why? So tragically, atrial fibrillation can lead to these outcomes, hospitalization, transient ischemic attack, heart failure, cognitive impairment, dementia, stroke, and death. But we know that it doesn't have to be so if we treat it. And a lot of times, you know, when we're thinking about interventions, you know, we're asking ourself, well, we know it decreases the surrogate endpoint, but does it really have a meaningful impact on these heart endpoints? So let's look at the association and relationship between a-fib burden and some of these things. So we know from the discern study that when someone has a catheter ablation procedure, the amount of a-fib they have in follow-up impacts their activity level, right? Our current guidelines say that everyone with atrial fibrillation should have a minimum of 210 minutes of exercise every week. Kind of hard to do that if you don't feel well and your functional capacity is pretty poor. So we know that a-fib burden is important for what patients can do and what their functional capacity is. We've also known for a long time, these are data from the Bradycare Registry of pacemaker patients initially presented by Sunit Mittal at these scientific sessions a decade ago. It's also interesting to think how we've come along this journey. It's very clear the odds of hospitalization with atrial fibrillation clearly increase with a-fib burden. We often have these big debates about how much is enough a-fib to merit anticoagulation. And we could have that debate for a whole month probably with no breaks, right? But I think we all understand and agree that the greater the exposure to atrial fibrillation, the greater the risk of stroke. And so that's been well documented. In the CABANA trial, we wanted to look at when patients had recurring atrial fibrillation, if they experienced a certain threshold of atrial fibrillation, were they at risk for cardiovascular events? And CABANA showed us that yes, when patients have 24 hours or more atrial fibrillation after catheter ablation or initiation of anerythmic drug therapy, they have a much higher hazard of heart failure hospitalization. They have a much higher hazard of all-cause death or cardiovascular hospitalization. If you'd say, well, clinical trials are one thing, but John, they're a select group of individuals who agree to be randomized. What do we know about the general population? So these are data from over 39,000 patients whose cardiac electronic implanted device data was linked to their data in Medicare. And what do we see when we look at patients and their atrial fibrillation burden? We see a very clear dose-response relationship between atrial fibrillation and cardiovascular clinical outcomes, including all-cause mortality, stroke, all-cause hospitalization, and CV hospitalization. We spend a lot of time focusing on heart failure, and rightly so. It's a significant problem for our patients and our communities. And we know from the ASSERT trial that when we see patients experience AF progression, they have a much, much greater risk of hospitalization. And that was defined in this study as the continuation of atrial fibrillation to episodes of 24 hours and greater. So you might say, well, John, those are all associations. What do we really have in terms of randomized data? And I'm gonna share one example. I could share others, but many of you may be familiar with the CASEL-AF trial, where patients who had paroxysmal or persistent atrial fibrillation and heart failure with reduced ejection fraction had a run-in period where their guideline medical therapy was optimized, and then they were randomized to ablation versus conventional treatment. And what do we see? We saw that over time, from randomization and the implementation of the intervention, we saw that the patients who underwent catheter ablation had lower cardiovascular death, hospitalization, and stroke. So in my opinion, and I'm probably biased because this topic is of great interest to me, I think this is one of the most important slides in our field right now. These are randomized data looking at the outcomes from the CASEL-AF clinical trial, and it's a complex slide. Red is ablation, sorry, red is no ablation, blue is ablation. And it's showing you what is the relationship between the reduction in AFib burden and the risk of the outcome events. And what you can see is when the interventions result in a big difference in AF burden, you see a significant reduction in cardiovascular events. And when there's no difference in AFib burden, and the patients in atrial fibrillation all the time, you don't see any evidence of benefit. So there's two major points from this slide. The first major point is that people benefit from catheter ablation even when they have recurrences. And in many cases, even when they have fairly large loads of AFib burden, as long as it's reduced. And the second main message is that there is a very clear mechanistic link between the reduction of AF burden and improvement in outcomes. So in conclusion, AFib symptoms and discrete episodes are only part of the picture that we need to pay attention to when we're working with patients. AFib burden is a very important biosignature that's associated with hospitalization, heart failure, stroke, cognitive impairment, and death. And to randomize trials when we reduce AF burden, we improve outcomes. And how much AF burden is a much more relevant and patient-centered outcome, in my opinion, than an isolated measure of time-to-recurrence. And I thank you very much for your attention and the opportunity to speak about this topic. And we'll take questions at the end. We'll have a discussion, question and answer period. So the next speaker is Martin Aguilar from Montreal. And he's gonna speak on the topic, reported success rates of AFib ablation trials, impact of the monitoring strategy, and duration of follow-up. Thank you. Thank you. All right, so thank you very much and good morning. Just waiting for the slides to come up. It says that there are no slides. Okay, we're going to move on to the next speaker, who's Louise Sagan, who's going to speak on the topic, Important Outcomes of AF Ablation to the Electrophysiologist, Healthcare Utilization and Quality of Life. Thank you very much for the kind introduction. And I just wanted to say thank you to the Heart Rhythm Society for the invitation to speak on what's a really important topic today. I'm very pleased to see that we're seeing a paradigm shift in what's becoming important and recognizing that what's important to the patient should also be important to the electrophysiologist. So this is the topic of health care utilization and quality of life in patients with AF. AF is a burgeoning problem of epidemic proportions globally. And in part, that's due to an increasingly aging population as well as the accumulation of increasingly modifiable risk factors, which thankfully have found their way into the guidelines in terms of preventative measures to address AF risk and its management. Despite this, catheter ablation remains the cornerstone of AF ablation management. And AF itself is associated with significant morbidity and mortality risk. And importantly, adverse effects to the patient, namely quality of life and adverse outcomes, including psychological well-being. Catheter ablation is the most targeted treatment to offer sinus rhythm restoration and maintenance. And despite this, we have seen a relative plateau in the success rates. But it's important to understand that when we talk about the plateau, we're really defining success, as Jonathan very clearly articulated, as a binary outcome of either whether you have a recurrence or you don't. And increasingly, we're shifting towards this concept of AF burden as a more important and meaningful metric of outcomes to our patients. And I'm going to show you a little bit more as to why that's important. And Jonathan has spoken to a lot of this already today. This is taken from the CircoDose study. And I've adapted this picture from Jason Andrade's important work. You can see that this example shows a patient with high AF burden pre-ablation. And you can see that their trajectory post-ablation, you might not be able to see these small little blue blips along the way. But if you counted recurrence as an absolute binary term, you can see this patient's had three or four recurrences in the follow-up after ablation. And so in traditional terms, this would be considered a treatment failure. But importantly, you can see this patient has had a dramatic reduction in AF burden. And that can translate to very important and meaningful differences in quality of life and well-being, as well as reductions in health care utilization. And you can see in the CircoDose study, they showed the median reduction in AF burden was actually more than 99%, so very impactful findings. Now, on the other side of the spectrum, you can see that if you only look at symptomatic AF episodes or symptomatic AF burden, you actually overestimate the treatment effect by up to 25%. So it's important that we don't necessarily take it to one extreme or the other. And we do consider AF burden in its totality and possibly look at other metrics as well. So traditionally, we've probably considered, more importantly as a priority, acute procedural success, whether we achieved isolation of the veins and our other ablation targets, whether the patients had any recurrence at all, which we're moving away from, and safety profile. But what's really important to our patients is whether they feel better, they can take less drugs, which are going to cause less side effects, and they don't need to come and visit us so often. So we really need to shift our focus towards how can our goals and their goals align better. So I'm going to first touch on psychological well-being. And this historically has not garnered enough attention, but thankfully, increasing literature is focusing on the psychological impact of AF. We know that patients with AF are far more likely to report higher rates of anxiety and depression. And AF in and of itself can actually exacerbate those symptoms. One qualitative study showed that up to 20% of patients actually expressed suicidal ideation. These are patients with AF. So it shows you how debilitating it can be. And very importantly, the remedial randomized study looked at patients with significant depressive symptoms at baseline and showed that those patients who underwent ablation fared much better with respect to reduction in anxiety and depressive symptoms and also to their AF symptom severity. So you can see that there's a close relationship between AF symptoms and mental well-being. So what about other metrics of AF symptom scores? There are many symptom scores that have been applied. Most commonly in the clinical studies would be probably the AF EQT score. And the CAPTAF study was a randomized study that looked at patients undergoing ablation versus antiarrhythmic therapy. And you can see if we adopt this traditional model of recurrence, whether they have recurrence or not, there was no difference between these populations. So you'd think, well, why bother with ablation in these patients? But when you nut down into the finer detail of this study, you can see that those who underwent ablation had significant reduction in the AF burden across every time point. And this actually became the most significant the further down the track you followed these patients. And this directly translated to improvement in quality of life metrics across all of the scales of the SF36 scores. CARBAN has already been mentioned today. And you can see that the AF EQT score improved to a greater extent in the patients undergoing ablation compared to medical therapy. And you can see that despite about 2 thirds reporting severe symptoms at baseline, only 15% in the ablation arm reported severe symptoms at follow up. And when you look at the sub-analysis, you can see this was favoring ablation across all subgroups other than heart failure, which I'll come to in a minute. And the improvement in AF EQT and symptoms was maintained in the ablation arm across long-term follow-ups. This is not an incidental finding, and it's not a reporting bias. The recently published Kapler long-term sub-analysis, this looked at three-year follow-up of these patients, showed a continued increase in quality of life scores reported by the patients. And again, across all domains. And you can see in the middle, there was an inverse relationship between AF burden and improvement in AF EQT score. And again, to the right, you can see in subgroup analysis, all of the subgroups showed a favorable outcome with ablation in terms of the improvement in AF EQT score, even in long-standing persistent AF, which might surprise some people. And even in patients who had a health catalyzation event, there was still an improvement in AF EQT score. So ablation, even if you reduce their AF burden, and even if they have a health catalyzation episode, their AF EQT, their quality of life, will still improve. So we talked about how Cabana showed that the subgroup with heart failure may not do quite as well. So there was actually a heart failure sub-analysis. This is 700 of the few thousand patients. And you can see that in the heart failure subgroup, this is HEF-PEF and HEF-REF combined, there was a significant improvement in AF EQT score maintained out to the longer term, favoring the ablation arm. And that was also true for the MAF-C score. So you can see we've now got a plethora of studies, both observational and randomized, showing dramatic improvements compared to baseline in terms of AF EQT score. And now we have the benefit of the ADDvantage AF study, which was just presented at the meeting on Thursday, which I'll talk about later. So some of you in the audience may be wondering, isn't this just a feature of having an intervention? The patients know they had the procedure, so they're going to feel subjectively better. It's the placebo effect. Well, the SHAM-AF study sought to directly address this question. So you can see this is a randomized study of 126 patients randomized either to ablation or a SHAM procedure with phrenic nerve stimulation. And in this study, they showed that those undergoing ablation actually reported a greater improvement in their symptoms across all the time points. So not just at the follow-up, but at each time stage. And you can see that this was true irrespective of the subtype of AF you had, whether it was paroxysmal or persistent AF. And this is the change in AF burden seen in those subgroups. So let's pivot over to health care utilization. How does improvement in symptoms help to also benefit our health care system and the costs to the health care system? And why is this important? We know that there are obviously direct costs, things such as ER visits and hospitalization and need for cardioversions and repeat procedures. But what about loss of activity and employment and financial implications for the patient? And these are things that can be difficult to measure. The ORBIT-AF study, which is not randomized, but a very large registry of more than 10,000 patients, showed that patients with symptomatic AF are far more likely to be hospitalized. So that's really important. It shows that relationship very nicely. Cercodose, I'll pivot back to again. We saw a dramatic improvement in AF-EQT score, irrespective of the type of ablation technology used at follow-up. And you can see this directly translated to significant reductions in all of the health care utilization parameters, ER visits, hospitalization, and need for cardioversions. The sub-analysis of the Kapler randomized study. This is a study of 338 patients with persistent AF. Rose Crowley, one of our PhD fellows, has recently published this analysis of health utilization in these patients and showed two important findings. Number one, if you have recurrence of any kind, you're more likely to access the health care system. But you're far more likely to do so if you have persistent recurrence. And Jonathan touched on this earlier. But importantly, in the Kapler follow-up, 2 thirds of those who experienced recurrence actually had paroxysmal recurrence. You're already changing their phenotype. And that probably means that they would have had a significant reduction in their burden. The Optum database, again, looked at patients with paroxysmal and persistent AF and looked at health care utilization as well as the costs of the health care system. And you can see, irrespective of whether you had paroxysmal or persistent AF, there were significant improvements in health care utilization post-ablation compared to 12 months pre-ablation. This was across most of the domains. The antiarrhythmic drug use was similarly reduced to a greater degree early on in paroxysmal AF. But they felt this was driven by the patients with persistent AF remaining on drugs in the first six months. And you can see, in terms of the cost to the health care system, in the first 12 months, actually the overall costs, which is to the far right, are a little bit higher. And this is a bit disappointing. But you can see in red that it's actually driven by the need for repeat procedures early on. But when you look at the 18-month analysis, you can see that the overall cost saving is present. So even when taking into account the need for repeat procedures in the longer term, the improvement in terms of cost to the health care systems are established. And what about AF burden thresholds? And Jonathan's spoken a lot about this. So I'll try not to spend too much time. But is there a threshold that tells us we can ignore this amount of AF? And I think we haven't quite answered that question. But I'll show you some of the literature. In the CERCODO study, they actually found there was a relationship between the longest duration of AF episode and AF burden. And the magic number was 0.1% AF burden or less than one hour longest AF duration episode. And so therefore, they determined that this area seemed to be the sweet spot, if you like, that yellow box. And they found that patients who had an AF burden less than 0.1% had a similar or comparable rate of health care utilization compared to people who had no recurrence. Whereas if your AF burden was more than 0.1%, then you're more likely to require health care utilization. And the same was actually found with an episode duration of more than an hour. So you can see that the relative risk was dramatically increased when you exceeded that threshold. ADVANTAGE-AF was just recently presented. This, again, is non-randomized, but still very insightful information. Sorry for the picture quality. I took these screenshots during the presentation on Thursday. But you can see that they were able to actually reproduce or replicate the findings from Cercodose. But this is in a persistent AF population. Remember, Cercodose was paroxysmal AF. And they again showed that as your burden increased to more than 0.1%, your health care utilization dramatically increased with a relative risk of 11. And they showed that patients who required health care utilization had a far higher AF burden compared to those who did not require health care utilization. And again, you see with the longest episode being more than an hour, health care utilization increased again dramatically with a relative risk of over 10. And I'm just going to finish on this point. Jonathan made the point, too. What about the heart failure population? Surely an AF burden of 0.1% is not going to be quite as meaningful in heart failure patients. We know that they're far more likely to have recurrence. And they're far more likely to have persistent AF recurrence. Now, the Castle AF study sought to look at this. It's important to note that it wasn't powered to look at this endpoint. But it did evaluate hard endpoints. And what they found is AF burden less than 50% at follow-up was associated with favorable heart outcomes, so reduction overall mortality and hospitalization. And so that suggests that in the heart failure population, we've got a little bit more leniency with regard to AF burden. As Jonathan mentioned, having a bit of AF, as long as they've had a dramatic reduction in AF, can still be very protective, particularly in these patients where it's so prognostically advantageous. So the take-home message is that AF recurrence in and of itself alone has become somewhat obsolete. Ablation results in significant reduction in AF burden, which directly translates to improvements in well-being, both psychological and physical symptoms, and reduction in health care utilization. And this is present in real world data and randomized data. And the next steps is really understanding whether these thresholds are sufficient, whether we need to study these thresholds in more prospective, randomized fashion, and how does this translate to meaningful endpoints for our patients. And I'll end on that note. Thank you very much. All right. Thank you, Dr. Sagan. We had some technical difficulties with Dr. Aguilar's talk, so hopefully we'll be able to circle back once that talk gets uploaded. So we'll move on to Dr. Mohan Viswanathan's talk, Timecourse and Significance of Recurrence Arrhythmias After AF Ablation, Implication for Guidelines in Clinical Trials. Well, thank you, Dr. Hahn, Dr. Calkins, for the kind invitation and the organizers to speak to you today. So we've heard some very nice presentations by Louise and Jonathan about the idea and the notion of reduction in AF burden, and I'll kind of take this along those lines to see and talk a little bit about timecourse and significance of recurrent arrhythmias after AF ablation and what can these provide implications for guidelines and clinical trials. So there's a few disclosures there. So atrial arrhythmias after AF ablation, we know they're common, we know that, in fact, looking at a Danish registry recently published of 7,700 patients between 2010 and 2018, so there has been a wide variety of treatments potentially in that group, but it's a real world analysis looking at these individuals, the risk of recurrence after an index event without any rhythm control is upwards of 90%, so we know it is a progressive illness. Ablation, obviously, has become a mainstay of treatment, and in this registry, over five years after the blanking period of 90 days, you had a recurrence rate of 52%, we know that. We know that after, as we look beyond a certain number of years, there will be recurrences. And they used a very clinically relevant definition of recurrent AF, a composite endpoint of use of antiarrhythmic drugs, hospitalization for AF, as we've seen. These are the things that are actionable and make an impact on patients, as well as all of us as clinicians as to how we act on them, as well as the need for redo ablation and cardioversions. So what is the definition of recurrence? How can we really get at this? Because that is what we really want to make an impact on. First, how does it manifest? We know this is either recurrent atrial fibrillation itself, macroenterine atrial tachycardias, typical flutter, atypical flutter. To the patient, again, these all feel pretty similar, right? To us, as clinicians, yes, if we see macroenterine atrial flutters, we look at that and say, okay, that's tractable, we can go in and maybe treat that so we have a little more favorability there. Focal atrial tachycardias, that's commonly seen in multiple sites. And then what about endpoints, right? We've touched on these. Perennially, 30 seconds of AT, AF, or atrial flutter has been an endpoint. Is it a little bit restrictive? We'll get into that. AF burden, how do we best define that? And what is the gold standard? As we've seen in SercoDose, they used implantable loop recorders and hence they used that very tight cut point of less than 0.1%. But is that feasible in every study in every individual? Maybe we can use intermittent trans-telephonic monitors, Holter monitors, patch monitors, things like that. So we won't belabor these. You know, recurrent atrial arrhythmias can manifest as macro-anterior atrial tachycardias in the left atrium, right atrium. Again, focal ATs in addition to AFib, okay? So what about this 30-second atrial arrhythmia burden? Or I'm sorry, atrial arrhythmia incidence versus AF burden? So it's been a traditional endpoint. Cabana, even a more recent ADVENT analysis by Vivek Reddy and colleagues. Fire and Ice. All these trials allowed us to speak the same language in that rather than each individual study coordinators using different definitions, the 30-second dichotomous variable of whether you had it or not was able for, it allowed us to compare these trials. But again, it does lack that clinical significance and clinical practical applicability as you've seen. And the patient-facing sensation of atrial fibrillation. And AF burden, or atrial arrhythmia burden has become more and more favored as an endpoint. So let's look at the ADVENT trial, a more recently published trial. Again, it's not that important to make the point about PFA versus RF ablation or cryo. But they randomized 600 patients, about 300 to each group. They used two 72-hour Holter monitors at six and 12 months as well as weekly trans-telephonic ECGs after the blanking period for one year. So quite a number of data, quite an amount of data. And they defined AF burden as the greater of two calculated values, the percentage of atrial arrhythmia over the total period of Holter monitoring or the percentage of weeks of trans-telephonic monitoring over the total number, number of weeks that actually had an atrial arrhythmia over the total number. So in that regard, we see here, when we look at the cumulative group on the left in panel A, the vast majority had a recurrence rate of less than 0.1%, whether you had RF or PFA. If you look at breaking them down in B between PFA and RF, granted, very similar. There's some clustering at around 5% and then the group around 50%. So really, that group, the larger group probably did not get benefit or has a little more recalcitrant AF. But only a minority had the greater than 10% AF burden. So in this study, it was favorable. But this is what we're trying to see. If the patient sees this type of reduction, we also should potentially realize that that's quite favorable and maybe this is a better metric that we should use. If you look at this analysis and we look at initial quality of life, there really wasn't that dramatic a difference across the board. But if we look at actionable, clinically relevant activities such as redo ablations, cardioversions, hospitalizations, sorry, there seems to be a cut point between that less than 0.1% that was used in circa dose and that came out of the use of loop recorders. So that tight, stringent number or cut point of less than 0.1% versus greater than 0.1% up to 10% and greater than 10% really did make a difference in hospitalizations, cardioversions, and redo ablations. So if we're not gonna use the 30 second dichotomous variable of whether you had that or not, should we be this stringent? Well, the data would argue that we should be. And if we can measure that, granted that between 0.1 and nine was likely driven by, again, this group that was in the kind of three to 6%. But that being said, if we take AF burden, maybe we should be quite stringent on that and really use that strategy. All right, we'll change course very quickly about time course. So this Danish registry, which we alluded to earlier of 7,700 patient, first time AF ablation between 2010 and 2018. And what they were looking at is your, from diagnosis to your ablation and basically separated these into four groups, less than one year, one to two, two to three, and greater than 2.9 years. And what was seen here is that if you made your way to AF ablation, all comers, persistent paroxysmal, your risk of recurrent AF defined by these clinically relevant endpoints was significantly reduced compared to whether you're beyond one year. So again, this can have, again, an implication for guidelines and clinical trials that when we make a diagnosis of AF, we really should try to offer ablation upfront. And so in many respects, that's made its way into the guidelines, but can we be a little more aggressive about that? Another Danish registry, just from a little year, a few years earlier, this looked at the notion that we all have kind of adopted is the idea about the blanking period, right? We tend as clinicians to say, okay, I'm not gonna really lend a lot of credence to those short recurrences that occur within the 90-day period. But does an early recurrence within that 90-day period portend a late recurrence? And in this analysis from 2021, granted it again spans 7,300 individuals, all comers, persistent paroxysmal between 05 and 17. So unlikely to have used PFA, unlikely, well, likely to have used multiple strategies. In this group, 38% had an early recurrence, and we're talking zero to 30, 30 to 60, and 60 to 90. And if you look at that, and let's go through this a little bit. Don't see if I can have a pointer here, but let's see if we can do this, sorry. Well, anyway, so if we look at the zero time point, that is at 90 days. So the lower line is if you did not have a recurrence at all even if you had a recurrence at zero to 30, your risk of a late recurrence at two years was slightly above 50%. If you had no recurrence, it was around 30%. So there itself, there's a difference. And if you, later in the blanking period, if you had a recurrence between 30 to 60 and 60 to 90, your risk of late recurrence was upwards of 75%. So maybe the notion that these early recurrences do not necessarily portend anything in the future may not be 100% accurate. And we'll see as we need new data. But it also does suggest something in that should we be more aggressive in suppressing those early recurrences with antiarrhythmic drugs or we don't tend to do redo ablation in that early phase. So what are the take home messages here? So possibly using the 30 second incidence of AT or AF has been too restrictive. And in fact, on the patient side, what we've seen so far is that it likely has been because if the patients feel benefit, that's really what we're looking for. And it may have been underestimating the benefit of ablation. This may have been really borne out in the CABANA trial and some earlier trials. Atrial arrhythmia burden really is, seems to be more relevant. Earlier referral to AF ablation seems to have significant benefit. We've seen this in VT, we've seen this in other arrhythmias. And that this notion that like anything within 90 days, we're not gonna really pay it much attention to, maybe we should start revisiting that a little bit. We'll see in due time. And how do we translate these two guidelines in clinical practice and clinical trials? So in summary, probably we should be using different methodologies of definition potentially. And we probably have to come up with some strategies to have some agreement there on atrial arrhythmia burden as an endpoint moving forward. Earlier referral seems to be beneficial. And in this blanking period, the time course notion, an early recurrence possibly does portend a late recurrence. I mean, we can probably surmise that. And should we be more aggressive with antiarrhythmic agents potentially as some individuals and many of us do, is to use antiarrhythmic drugs to suppress those early recurrences while healing and things occur to potentially forestall late recurrences. And you know, atrial, I mean, I'm sorry, antiarrhythmic drugs will remain a mainstay of treatment even in this era of aggressive catheter ablation. So maybe there's a role there. Thank you very much. Okay, so now we have Martin Aguilar is back to talk about reported success rates of AF ablation trials impacted monitoring strategy used during the follow-up. Take two. Thank you. All right, good. So good morning, thank you very much. And I'm sorry for the technical glitch. So today I'll be discussing an often overlooked but crucial aspect of AF ablation trials. And that is the role of post ablation rhythm monitoring strategies and how they have a dramatic influence on the reported success in clinical trials. So if you look at these three important studies, early AF, stop AF, and cryo first, all these studies enrolled very similar patient populations consisting of patients with paroxysmal AFib undergoing their first ablation procedure with fairly current technologies. Yet despite these similarities, the reported success in the ablation arms ranged from 57% to 82%. That's a 25-point spread, which is quite remarkable for studies looking at the very similar question. However, an important difference between the studies was how they monitored for arrhythmia recurrence, as shown on the slide. So the question this presentation aims to answer, at least in part, is how much of this variability in the reported success is due to how we monitor for arrhythmia recurrence after an ablation procedure, especially in the setting of a clinical trial. So if we start by looking at what the guidelines recommend, so the recommendation is that for the clinical trial setting in the absence of continuous monitoring, a minimum of 24-hour continuous Holter-type monitoring should be considered every three months for the first year, ideally in combination with symptom-based monitoring. And where available, longer duration, up to 14-day recordings are preferable. Now, three 24-hour Holters is equivalent to monitoring three days during the entire follow-up, whereas three 14-day recordings is equivalent to 42 days of monitoring. That's a 14-fold difference in monitoring intensity. And so we see that there's a fair amount of discretion left to trialists on how they monitor for arrhythmia recurrence after ablation, even in the clinical trial setting. And so again, the question we're trying to answer is, how does the type of post-ablation rhythm monitoring impact the reported success? So to answer this question, we perform the sub-analysis of CERCODOS. So just as a reminder, CERCODOS is a randomized controlled trial that enrolled 346 patients who had paroxysmal efib and were undergoing their first ablation procedure. And they all had an implantable cardiac monitor. So as already presented, the one-year arrhythmia-free survival with continuous monitoring in CERCODOS was 52%. Now, what we did is that we took the ILR data from CERCODOS and simulated different non-invasive monitoring strategies. So in the same trial using the same patients, if you apply the minimum guideline recommended monitoring of three 24-hour halters, you would get a reported survival of 92%. And as the monitoring intensity was increased, the survival estimate got progressively closer to that of the implantable monitor. So what we see is that the reported success in the same trial with the same patients can range from 50% to over 9% just by changing the type of post-ablation rhythm monitoring strategy. This table shows the different types of monitoring strategies that we evaluated in the sub-analysis with their corresponding arrhythmia-free survivals, sensitivities, and negative predictive values. And what you can appreciate is the wide variability in all of these metrics. And so what this tells us is that the type of post-ablation rhythm monitoring has a major impact on what we report as success in the clinical trial. And as a result, outcomes from trials that use different post-ablation monitoring strategies cannot be directly compared. And that becomes a major problem when interpreting the literature because of the lack of standardization in post-ablation monitoring. So to explore this further, we conducted a systematic review of randomized control trials published between 2014 and 2024 that enrolled patients with their first ablation procedure for paroxysmal AFib and that reported Kaplan-Meier type survival curves with intermittent monitoring. And so the search returned 42 trials, totaling over 10,000 patients. And this table shows you the 42 trials that we found with the systematic review with their corresponding monitoring strategy after ablation. And what we found was a wide variation on how these studies monitored for arrhythmia recurrence after ablation with protocols ranging from three 24-hour halters up to four seven-day monitors. So that's a nine-fold difference in monitoring intensity. Sorry. And not only was there a wide variability in how patients were monitored after ablation, there was a lot of variability in the reported success, as you can see in the tables. So this figure just shows you the one-year arrhythmia-free survival as reported in these 42 trials. And this variation raises a critical question. And the question is, if one trial monitors less intensively than another and reports a better success, is that truly a better outcome or just a reflection that they missed a whole bunch of recurrences? So that led us to ask the following question. Can we normalize the reported success from different trials adjusting for the differences in monitoring strategies? And so we developed a machine learning algorithm with the goal of normalizing the reported success from trials using different monitoring strategies as if they all had the same type of monitoring. And the idea is that by normalizing the reported success to a common monitoring strategy, we felt like the trials would then become more comparable. So without going into the details, we use, again, the circuit dose data to train and internally validate the model. We then use the dataset from early AF, which is another praxisimal AF trial for which we had ILR data to externally validate the model. And then after internal and external validation, we applied the model to the 42 trials that we had identified in the systematic review. So in other words what the model takes as input are the success rates and monitoring strategies for any given trial and it outputs a normalized success for a standardized or common post ablation monitoring strategy. This shows the internal and external accuracy of the algorithm with the root mean square error in the range of 0.2 to 2.1 percent in normalizing the arrhythmia-free survival for the different monitoring strategies listed in the table. So we felt that like the model performed pretty well. This is an example of how the algorithm works. So this trial used 24-hour Holter and trans-telephonic monitoring and the reported success in the study are shown in red and then you can appreciate how the success rates vary as they're normalized to different monitoring strategies. So for example in group A the reported success was 70 percent and what the algorithm predicts is had these patients been monitored with three 7-day Holters the expected survival would have been a 56 percent or 29 percent with an implantable cardiac monitor. So this figure shows the main result of this analysis. So the blue box shows the reported arrhythmia-free survival from the 42 trials using a whole bunch of different monitoring strategies. Now if we use the algorithm to normalize these trials as if they all used three 24-hour monitors we get the red box with a slightly higher median survival and then we repeated the the process with increasingly intensive types of monitoring up to an implantable cardiac monitor in brown. So from this we see two things. Number one again the type of post-ablation monitoring has a major impact on the reported success rate and number two the reported success rates in published trials with a blue box largely overestimate success had patients been continuously monitored which is the brown box and that's by a fairly large margin of 43 percent on average. So this brings us back to the more philosophical question of what success means after AF ablation because again despite all of the technical developments in the field of AF ablation the definition of success and how we measure it remains ill-defined and beyond the type of monitoring strategy that I've discussed there are a number of variables that have been discussed during the session that need to be studied and standardized in order to unify how we report outcomes because otherwise we are spending a lot of time and resources generating data that then are very difficult to integrate. So in conclusion there is no standardized rhythm monitoring strategy in published AF ablation trials and that is a problem because the reported success is highly dependent on how patients are monitored after ablation. As a consequence comparing outcomes from trials that use different post-ablation monitoring is a bit like comparing apples and oranges unless the reported success rates are normalized to a common type of monitoring as we did with our algorithm or trials are reported using a standardized type of monitoring. Otherwise it's very difficult to make any meaningful comparison between the trials. I'd like to thank my collaborators and thank you for your attention. So we now have 15 minutes for discussion and questions and discussion but let me start out we have a patient representative on the panel Mr. Daniel Green and I'd like to get his comments on the talks that you heard and what what matters to a patient with AFib. Do you want to share any comments about what you think is important from a patient perspective. Well first of all I'm a little depressed to hear that it's a 52% chance that I'm going to recur and what's probably interesting about that is that I'm sure I was told that and again as a patient I think that what that really means is that we don't remember a lot of things that were told. I personally had paroxysmal so when you talk about burdens I think of my burden as being you know I had five episodes over five years that were very very symptomatic so for me failure would have been recurrence. Decreasing my burden saying well you're only going to have some of it some of the time I would consider I would have considered that a failure and that will become a failure if that's what happens. Now I realize that for a physician and for studies that's not necessarily a failure decreased burden has better health results but as a patient it's not necessarily thought of the same way. The other thing from a patient standpoint which I know that these talks were more about the ablation itself but as the post-operative period and was mentioned briefly about medications for example. I was fortunate enough to have a wife who's a EP and so as soon as I had very dramatic symptoms I would know when I had them and I would get cardioverted within 24 hours so I wouldn't have to be on any sort of blood thinner and so I went four or five years with maybe four episodes or five episodes and they became more and more symptomatic and eventually I did have them I had a ablation and it's been very successful Greg. I haven't had any recurrences but where I was not on a blood thinner before surgery or before the ablation I find myself on a blood thinner afterwards. What makes it even stranger to a patient is that I was 64 when I had the procedure so I didn't have to be on it for the first few months but as soon as I turned 65 I met the criteria I've had hypertension and a history of AF so I'm now on a blood thinner and luckily I'm not I was able to get off the other medications which were very important but I would love to not be on blood thinners. Again I know it's beyond what we're discussing today but you know with for example a watchman maybe combined procedures might be something that you would want to think of in the future when if somebody you know is going to have to be on a blood thinner perhaps you know say we could do the ablation and at the same time put a watchman in if that's I don't know I'm not sure how feasible that is but I'm just saying so from from some standpoint it's beyond just whether or not you have recurrences what you can do afterwards so I am limited I ski and I surf and I so I have to admit that those times out I won't take my blood thinner the few days that I do those things so but in terms of the procedure itself in my opinion success is not having to have to be cardioverted or have to go through another procedure but I do understand that especially after now that there is probably a fairly good likelihood that I will and that's reasonable but the patients need to be you need to drill into their heads that these procedures aren't necessarily going to get rid of their problem forever. Thank you any other questions? Mike. I'm Mike Hiziklitz. First of all the talks have been absolutely outstanding and the comments also so that we're in an environment where advances in medical care have produced the types of longevity the likes that I certainly never anticipated so we're dealing with a success story and I agree with the comments in terms of AF ablation that the best results definitely occur if the patients are referred early and my question to the panel is in that situation based on all the discussions I've heard at this meeting what type of ablations do you recommend for these early referrals and that's what I do on a regular basis early referral for intervention. The second question is the use of anti-arrhythmic drugs and I want your opinion on these and one thing that shocks me is the continuous use of amiodarone which from my perspective is a toxic drug for which we now have other alternatives. I'd be interested in your view of that so I think that those are my questions. Sure I mean if I think Mike the one thing that I think should be super emphasized from your comment is early referral and I think Jonathan Coleman is in the audience and his group did a really important clinical trial where they tested the hypothesis and Jonathan just come to the mic if I get any of this wrong they tested the hypothesis that immediate ablation versus delayed ablation and they saw no difference in recurrence, AF burden, quality of life but the huge difference was the patients in that clinical trial got outstanding care and the ones treated with drug therapy had excellent suppression of their AFib so the key concept is getting the patient referred early and treating the disease right away rather than letting you know letting it get out of hand and adverse remodeling occur and for some patients that's going to be upfront ablation and to answer your second question in our center that's going to be PFA but I think depending upon where you are in the world and what center you know it should really be the ablation modality that center has the most experience and comfort with and delivers the best results but at our center that's pretty much almost become 100% PFA. Yes I think I'll add on to that is again it's early referral for rhythm control right so it's not just ablation but keeping people in sinus rhythm is going to be the key point there so we have a lot of questions actually from the audience please keep sending them through your app so I'll give you a panel a few questions let's see so this is a good one absolute risk of recurrence is probably too strict and represents a pendulum swinging too far in one direction what sort of lower bar thresholds do members of the panel think we should be careful to exclude as outcome variables looking towards the future how do we construct guidelines that prevent individual investigators from cherry-picking successful outcomes I think dr. Aguilar kind of addressed that that's a very good and difficult question so for sure time to recurrence is a very strict metric because somebody can recur with encircled those with the two minutes of a fib and that patient would have counted as a recurrence as a treatment failure I think there was a slide showing the the relationship between episode duration and health care utilization so one of the variables that we didn't I think explicitly discuss is the how we should define an episode of AF now it's it's set to 30 seconds or two minutes and in different trials but clearly having three seconds of a fib is not clinically significant for most patients so that's certainly another another important variable that I think needs to be reassessed especially for the guidelines in terms of defining success after an ablation procedure maybe I'll comment a little bit on that too I mean you showed really nicely that the success rate really depends on type of monitoring and so I think it would be a little bit stringent to demand that we do loop recorders for everybody but you know you said like with the 14 day monitors at three month intervals I mean that's a 14 fold increase than holters at least we can start with something like that because the 14 day monitor has become quite ubiquitous and it's the form factor is very reasonable of patients and it provides us a little more information but there's a gradation there going from holters to loop recorders so I think the guidelines should start to really maybe become a little more uniform in terms of little more monitoring than just holders yeah I think that's a tough one right because I think in your circuit dose when you looked at that there's a sweet spot that you guys looked at that said if you do for seven day or if you do to 14 day you get sort of towards that ICM level of detection right and I think that brings us really back to like the patient perspective because you have to understand like ILRs are not available everywhere they're costly patients may not want to have invasive monitoring that's the other thing and as we grow into this other space of wearables etc I see Rob Rod Passman in the audience here stuff to mention that but I would love to hear you know what you think Dan about that like do patients want to have ICM's I think that's a huge question right because maybe patients don't want ICM's I personally would have loved to I'd love to have one now put a loop recorder in because I do for me again I think one of the main issues is is how badly do I really need to be on a blood thinner but also just to know you know you talk about burden am I am I do I have a fib that I just don't really realize that I have obviously is that important I guess if it's asymptomatic it's not important for the most part I would let you guys be the answer to that so it would be important to know I actually was word enough I I had a Z a patch something like that I had one of those for a week somewhere post ablation you know I'm a physician myself and married to a physician so I may be a little bit more compulsive about those things I don't know if the average patient would care they would probably just want to know are they symptomatic or not all the time every little premature you know that you have that perspective right you're physician patients how do we sort of get through to our patients about emphasizing what the outcome should be what the expectation should be how do we having that perspective what do you what do you think is it just sort of drilling down is it like repesh repetition is it getting patient you know representatives on there you know I I'm gonna be a little bit cynical here and having been both a doctor and now a patient I used to tell my patients things over and over and over and over and they wouldn't remember and I'm sure I was told things over and over and over and I didn't remember and so all you can do is do your best to make sure that you do say the right things and tell them the risks and so forth yeah so which antiarrhythmic drugs are you using that I'd be interested in your opinions on that and then I'll sit down thank you for the question I'm from Australia so some of the drugs that are available in the US we actually don't have access to I think for the broader AF population without heart failure I'm very comfortable using flaconide and I find it's usually best tolerated in the absence of structural heart disease or other contraindications it does require monitoring and cautioning patients about some of the reasons it might need to be stopped but usually for AF suppression it seems to be best tolerated and most effective with an avian odor blocker and then sodolol is an alternative but I do find in a subset of patients and typically younger women and also athletes it's not well tolerated so sodolol can be problematic and then amiodarone I do typically reserve for the heart failure population I'm very nervous about using flaconide or even sodolol just based on very historical data and and I think we need some contemporary data to understand whether these drugs might be utilized in heart failure patients particularly those who have devices so that might be a area of future research and I think the importance with amiodarone is diligence around the time or the duration patients on these therapies and we did a study looking at time to ablation the AF and heart failure population found it was actually really important to act earlier and that might enable us to rationalize those sort of therapies earlier on in the treatment stage. What about dronadarone? I can't really comment because we don't have access to it but maybe some of my U.S. colleagues might comment. You know, dronendron was touted as an amiodarone equivalent and really has not panned out that way. It does cause quite a bit of bradycardia and slowing of heart rate, but it's not as effective as an antiarrhythmic agent, in my opinion. But, you know, when we are in this population where we can't use flecainide or propafenone as a 1C antiarrhythmic drug, we tend to use either sodalol, dofetilide, both of which, you know, require QT monitoring, and amiodarone and dronendron, but dronendron has a use behind those other agents, in my opinion. Or if it comes to an intolerance stage with the other ones, we resort to use of dronendron, knowing that it may not be very effective as an antiarrhythmic drug. Great. Dr. Schmidt? Yeah, thanks for a terrific session. I enjoyed all the presentations and also the discussion. I think in the past 20 years, it was more than justified to use, like, intensive monitoring strategies after catheter ablation to detect arrhythmia episodes, arrhythmia recurrences, even episodes that were only 30 seconds long, because we had to learn what is really the power of catheter ablation. Now, 20 years later, we all, I think, agree that we cannot cure atrial fibrillation with ablation, but we reduce burden and we reduce symptoms, and that's the central parameter, I think, for patients, that we reduce symptoms and not get rid of the atrial fibrillation in total. So isn't it time to change our approach to clinical trials? I mean, insertal monitors are certainly valuable for certain questions, especially temporal association between AFib and stroke, et cetera, if you look into this, but if we only look into an ablation technology or an ablation approach, it's, I think, key to know how does the patient feel. Is he not symptomatic anymore, less symptomatic, et cetera? So can't we change endpoints for our clinical trials with the focus on patients, and maybe if we look into our colleagues from general cardiology, et cetera, shouldn't we maybe find a new classification for atrial fibrillation recurrences? There are some that lead to repeat ablation, major intervention. There are some that only cause symptoms for a little bit of time, minor event, maybe. So maybe we can find a category for severity of atrial fibrillation recurrences, too. Yeah, I think, Boris, that's outstanding because I think we talked about a little bit of that in Stanford Biodesign. I had a slide about how maybe 2025, we've talked about burden for 1,000 years. Maybe 2025 will be the year that we actually understand that it's not just stroke that affects our patients and that patients find worthy and impactful. It is healthcare utilization. It's cardiovascular outcomes. It's things like horrible symptoms that are infrequent but terrible to the patient, and things like heart failure that you mentioned. So I think there are many endpoints we probably should be looking at that were not that matter a lot to our patients. So I 100% agree with you. So there's, I think you're aware of the effort that Paul Wang and Pete Weiss are leading to define new endpoints for catheter ablation working with the FDA. So hopefully by the end of the year, there'll be some new guidance on that, but I think your point is very well taken. Just say a few things in that regard. I think one opportunity we have that we keep whiffing on and missing is the ability to use composite measures like the Winn Ratio, where you can have a measure of atrial fibrillation recurrence, a biological exposure variable. You can have cardiovascular outcomes. You can have quality of life and symptom scores. Some people don't like them because they're difficult to interpret, but I love them because I think they give you an integrated measure of many things that are important to patients. I think the other thing is we talk about ILRs as the only way to measure a foot burden today, but we know that, you know, a few years from now, we may have a T-shirt you can wear that can accurately give you AF burden, and our wearables are going to get better. So if you want to hear more about that, please register for HRX. It's in September in Atlanta. We hope to see you there. Jonathan is not talking. May I have a question? Of course. I agree with your recommendation to early refer to catheter ablation to the treatment, but what's your definition of early? How many episodes of atrial fibrillation and paroxysmal ablation do you require to refer them for catheter ablation? And persistence is quite easy because persistent is persistent, but in paroxysmal ablation, how long to wait after how many episodes to send them? Does anyone want to take that question? I don't think there's a specific number of episodes, and I think you do have to apply a pragmatic approach and use clinical judgment, but the contemporary guidelines would suggest in paroxysmal AF that catheter ablation should be considered first line. So I think it's reasonable in patients, particularly where you're looking to avoid regular antiarrhythmic drug use or there's a preference to avoid antiarrhythmic drug use to rationalize therapy, where there's highly symptomatic episodes. I don't know that there's a specific magic number that would necessarily be applicable for every patient, but certainly for, you know, class 1 indication for paroxysmal AF. There's another question submitted by the audience on using smartwatches to measure AFib burden. Does anyone want to make a comment on we don't need implantable monitors, we can just rely on your Apple Watch? So my opinion is that we have to be careful about measuring AF burdens or interpreting AF burdens or not with continuous monitoring. We did a study, and if you do, if you measure burden out of halters, you will significantly overestimate the burden compared to continuous monitoring. And so I think there needs to be further work on understanding the relationship between what burden means if you do it on a halter, on a smartwatch, or on whatever other type of noninvasive monitoring as compared to the gold standard, because having, let's say, a 1% burden on an implantable cardiac monitor is not the same as measuring 1% burden on a halter. I think we have to be careful with the smartwatches. They're both our friend and our foe, in the sense that we have the ability to capture these episodes earlier. So when your patient comes to you and says, and you haven't caught the episode with a halter and then a patch or other forms of continuous monitoring, that's where the watch is really helpful. So you instruct the patient, take your recording at the time of your symptoms. There's a couple of limitations. One in particular is the watches are not perfect. The algorithms are still not sophisticated enough to distinguish between true AF and things like atrial ectopy, and you get RR variability, which confuses the algorithm, and then it spits out that possible AF, and then the patient's rushing off to the ER. So I think that is a problem. The point that was already made about the fact that the ECG monitoring has to be initiated by the patient, so it's not continuous ECG monitoring, so AF burden's not going to be accurate. The patient's not going to sit there taking ECGs all day long. So I think that that might be the next iteration or some other forms of monitoring, but I do think we have to be still cautious in how we utilise wearables in this space. Just some practical tips for those in the room practicing medicine in the U.S. The current Apple Watch AFib burden algorithm will only report a lower bound of 2%, so it's important to understand that. We've looked at it in a bunch of our device patients. It's a pretty good reporter as an estimate, so if the burden goes from 2% to 4% or 10% to 20%, their AFib burden typically has doubled, but whether that's really 10% to 20% or 30% to 60% or 5% to 10% is kind of tough to sort out, but technology's probably only going to get better as we move forward. Yeah, I think I'll add on to that is the key point here is not truly continuous, right? Like, I think our patients come to us often and say, well, I'm wearing the watch all the time, even when I sleep. You have to understand that these algorithms, as they stand, only measure when you're still, right? So people aren't rocks. They move around. So I think you have to understand that, remind your patients it's great, wear the watch. When it tells you it's probably OK, come to us to make sure you get the proper EKG validation, but it's definitely not continuous, so the burden will not be accurate in the current state, but it will come. Other questions from the audience? I had a quick question for Mike. How do you perceive the AFib after the AFib lesion? Did you feel that the episodes were less intense? Was there a difference? Because we wonder about that. Like, is it just as intense after your AFib lesion, those punctuated episodes? Because we tend to mention that, that sometimes your sensation of AF may be different. Yeah. No, I've been symptom-free, so as far as I know. I haven't had any, so I've been very fortunate. I mean, this raises, I think, an important question because you've not been continuously monitored. I did it for a week. I wore a patch, but only a week. So perhaps you have asymptomatic AFib and you consider your procedure as a success because you're asymptomatic? Yeah, I would love to have a loop recorder just to find out. Yeah, I think that's an important point for the audience, right, is because your autonomics change with ablation, and we find that for sure from the discern AF trial that many patients' symptoms go away even though they have many episodes thereafter in frequency, duration, and burden. So I personally think my opinion is people should have a loop monitor until the devices get better so that we can monitor them, but many patients may not want it. Like I said, we're not sure what to do with the burden that we get if it affects their lives, but I think we're going to find that in the end, the burden will matter. One thing that's purely anecdotal, but I find patients initially, at least early on, seem to have this heightened AF awareness. They're almost anticipating an episode. So I have patients coming back saying, I have palpitations, you do continuous monitoring, you see it's atrial ectopy, and you have to reassure them that's actually okay, and we haven't seen it triggering AF. So I do think early on we probably do see that altered experience, and then hopefully over time where they haven't had, hopefully, established AF episodes, then that awareness might attenuate. Okay, we have another question. Does successful AF ablation translate into less anticoagulation? Let's start with John, and we'll go down the panel and see how we're dealing with this. I mean, I'll try and keep this brief. It depends on what your baseline risk is. If your baseline risk is high enough, it should not impact your anticoagulation at all. And what's high enough? If you meet the guideline recommendations, so two in a man or three or higher in a woman, I think we have some clinical trials that may change that in the upcoming two to three years, so it would be really interesting to see what they show. So in the Canadian setting, in my own clinical practice, I don't use ablation as a means to stop anticoagulation. So I anticoagulate patients based on their risk, which in Canada is the CHADS-64 score. So if they're above 64, everybody gets anticoagulation. Yeah, I would agree with John and Miguel in that we do, we use the CHADS-2-Vascular Scoring, and I reiterate the notion that like AF alone, it's not necessarily the AF that potentially portends your risk. Yes, we think that the atrium quivering like that may increase your risk of thrombus formation, but that being said, is AF just another marker of cardiovascular morbidity and mortality? And hence, the CHADS-2-Vascular Scoring. So I too do not see AF ablation necessarily as a way to get somebody off anticoagulation, but there are studies showing that once an AF ablation has been done, there is reduction in stroke, so we need to reconcile those two. I probably have a slightly different approach. I'm ultra-conservative. I would consider myself that way, and in Australia, we actually have used or modified the CHADS-VASc to now CHADS-VA, so we've removed sex category, and I think Europe has adopted that as well, and what that means is women and men are treated the same, and so anyone with a score of two or more is considered at elevated risk. One is still that slight grey zone, and zero would be low risk. We know even low-risk patients have a 0.2% per annum risk, so it's not insignificant, and it's hard to know what that means to the patient, and if they have a stroke, how would you feel about that, I guess. Patients with a score of two or more, I think it's straightforward from my point of view. I recommend long-term anticoagulation unless there's a major contraindication. The population in whom I find it really challenging is those with a score of one, and that's because it's that really difficult discussion, and if it's, as Daniel mentioned, if it's because you've reached 65, we know that age is not a binary term for these patients. We know that if you look back at the original CHADSVAS studies, as your age increases, your risk of stroke increases incrementally, but we've used this pragmatic cutoff as binary terms, so I tell patients, and we have quite a detailed discussion, and I say, as you get older each year, we know your risk probably does increase a little bit more each year, and so I'd probably lean more towards anticoagulation even with a score of one, but take it on a case-by-case basis, and then the one group I haven't fully reconciled what to do is patients who reach a score of one purely on the basis of having had a history of heart failure, particularly AF-mediated cardiomyopathy. These are the patients I really struggle with. They had heart failure. Now they don't have heart failure, so technically they're a zero, but they were a one. We know that they have atrial myopathy usually, and I don't know what's the right answer in these patients, so hopefully that will be the focus of future work. Yeah, Louise, I think that's the great population that is difficult because the guidelines tell us that you have a two-way indication to continue to monitor your recovered EF patients from attacking your myopathy from AF, right? But they don't tell you how to monitor, so I think that's a perfect study for someone to do. Go ahead. Practically speaking, in terms of monitoring post-AFib, if a patient's completely asymptomatic like he is, I guess there are two ways of looking at it. One would be to put an implantable loop recorder in. The other is to do nothing because the treatment's going to be the same. And if he's completely asymptomatic, I guess you're looking at downstream problems that have been elucidated. But, I mean, the cost of medicine keeps going up, and now we're talking about doing these things that cost money. And so I think, practically speaking, why are we even doing monitors in an asymptomatic patient? Post-ablation. Anyone want to comment? Go ahead. I mean, this is my personal opinion. I think there's a difference between the clinical trial setting and clinical practice. In my own clinical practice, I tend to do less monitoring than more because if patients are doing well after ablation, unless they had tachycardia-mediated cardiomyopathy, if they have a bit of AFib on a halter and they're asymptomatic, I won't do anything about it. So in my practice, I went from doing a lot of monitoring to doing much less and sometimes no monitoring if the patient is doing well. That's how I do it. Can I just comment on anticoagulation? Recently developed within the last year is the first and only score at the moment to quantify the risk of bleeding on patients prescribed a DOAC. It's called the DOAC score, recently published in Circulation. Full disclosure, we wrote an editorial accompanying the article. So this is a scoring system that you can use to predict the risk in an individual patient of having a bleed. And the type of bleeds, which amazingly are non-neurologic bleeds because the neurologic bleeds rates with the DOACs are next to zero. So this is an approach that could be used in terms of guiding that type of therapy. Any comments? Okay, on that note, I think it's time to wrap this up. Thank you, everyone, for your active participation. Thank you for the speakers for a series of wonderful talks. Have a great rest of the meeting and look forward to seeing you in Chicago next year.

atrial fibrillation

AFib ablation

early intervention

post-ablation monitoring

AFib burden

patient-centered metrics

psychological well-being

health care utilization

quality of life

monitoring variability

machine learning algorithm

patient expectations