We'll welcome everyone. Can you all hear me okay? Wonderful. So we're going to go ahead and get started because we do have a packed session for you. My name is Linda Schwartz, and it's my pleasure to welcome you to San Diego and Heart Rhythm 2025, the 46th annual meeting of the Heart Rhythm Society. If you have not already done so, please download the mobile app. This is how you can participate in live Q&A during the sessions. Please scan the QR code on the screen. When you see it, it's also in the app to access this session's Q&A, and then when using the mobile app, log in with your HRS credentials. Please note that visual reproduction of Heart Rhythm 2025, either by video or still photography, is strictly prohibited. Okay, so I'd like to introduce our first speaker. Tristan Pendergrass is a good friend and an assistant professor in the College of Allied Health at Harding University in Searcy, Arkansas. In 2022, Tristan helped build and launch the first of its kind master's degree program in cardiac function and interventional technology at Harding University. Tristan has nine years of cardiac industry experience, followed by nine years of experience teaching cardiac rhythm management and electrophysiology to allied professionals. Tristan also serves as an IBHRE ambassador and as an exam committee member for the Certified Rhythm Analysis Technician exam for Cardiovascular Credentialing International. Tristan's passion is building and delivering innovative education that improves cardiac patient care. Good afternoon, everyone. As these slides pull up, I'm going to be speaking on optimizing ICD detection and discrimination, which is a very large topic to talk about in 10 to 15 minutes. And first off, I want to thank some people, so my wife, Crystal, and daughter, Josie, my mentor, Mark Sweesey, Linda, Christine, Tammy and Dean in the Mayo team, Ken Turley and Todd Watson, my colleagues, and also my students. So this is definitely a career highlight to be able to be up here, even though the imposter syndrome is definitely kicking in strong. So we have a lot of ground to cover. We could spend weeks on ICD sensing, detection, hardware discrimination, so we're going to just list some relevant concepts in clinical science. I'm just going to have to take it that many have an understanding in this room and go ahead and get into the more advanced content. We're going to summarize two consensus documents, and we're going to examine some ICD optimization scenarios and consider some programming responses and best practices. First and foremost, when programming ICDs, programming changes can have life-saving or life-ending consequences, so you should never make any changes without having an order to do so. This talk also is not prescriptive, so it's not necessarily a one-size-fits-all approach, so please, you are the expert on your patients. And so hopefully take these nuggets and utilize them. And speaking of which, we're going to, this is San Diego-esque a wave for surfing. If anyone in here wanted to learn how to surf, if we have a monstrous 10, 12-foot barrel wave, that might not be the best type of wave to learn on, but this is from a linear perspective of how I would teach this in class, ICD indication system hardware, sensitivity, detection, discrimination, therapy delivery. And so we will not, we're going to focus on sensitivity, detection, discrimination. We will not achieve mastery in this talk, but hopefully it gets you out there on the water. So secondary versus primary prevention is going to continue to come up once we look at the consensus statement. ICD sensing, floor, threshold, start, decay, delay, there are some manufacturer differences as well as different manufacturers allow you to program different things. And so that's great to be cognizant of and aware of when dealing with ICD patients. Detection, so you have numbers of intervals detected, X of Y, and binning. Not all manufacturers use every type of detection. Some of it's proprietary, for example, binning with Abbott. These are, this is a core concept that we're going to mention, but you may have to dive deeper. There's definitely not enough time. This would take a day to cover in-depth ICD detection. ICD discriminators, so this is a list. Not all discriminators are available on every device. This is a list of various types. And whether you have a single-chamber device versus a dual-chamber device, not all discriminators are available. Some require the utilization of an atrial lead. So here in red is what's available for many manufacturers, single-chamber ICDs. So onset, stability, morphology. The others listed here have to require an atrial lead or atrial electrodes to utilize. So some clinical science now transitioning a little bit more context. I cherry-picked a few landmark trials that are informative and relevant to this discussion, so pain-free. ATP works. Hopefully everyone's using ATP for their patients. Patients will much prefer it over high-voltage shocks. RIT in 2012 took around 1,500 patients and put them into three arms, a conventional arm, a delayed therapy arm, and a high-rate therapy arm. And the takeaway, the main takeaway from this was that programming of ICD therapies of greater than 200 beats per minute or with a prolonged delay in therapy was associated with reductions in inappropriate therapy and all-cause mortality during long-term follow-up. So another trial relevant to this talk is the SIMPLE trial in 2015. So this randomized patients at implant to defibrillation threshold testing versus no defibrillation threshold testing primary prevention patients. And one of the takeaways of this was routine defibrillation threshold testing at implant does not improve shock efficacy or reduce arrhythmic death. This was more significant on the shock efficacy, less so on the arrhythmic death, but many publications since then have confirmed the association of shocks and mortality. Now getting around 10 minutes into more of the discussion today, the consensus statement. So in 2015, HRS released a consensus statement on ICD programming that any show of hands for anyone who's read this document. Okay, I figured not many. It's roughly an 80-page document, and it also had a 2019 follow-up similar to the two recent consensus statements we had on remote monitoring. So this document is great. It focuses on four clinical areas. There's two really relevant to our discussion today that I pulled a lot of this information from. So PREPARE, RELEVANT, MADE AT RIT, ADVANCE III, and PROVIDE all showed that longer detection times than manufacturing nominals did not negatively, double negative, impact the rate of syncopal events. Detection settings varied in these trials, but it did, they all were associated with not contributing and adding to syncopal events for patients. Altitude reduces showed that dual-zone programming is associated with fewer shocks. And more of the modern clinical trials that utilize discriminators have showed a markedly less inappropriate shock rate in the 1 to 5% range compared to the early trials that were in the 30s to 50%. So we have come a long way. The consensus statement, some of the main takeaways is that for primary prevention and for secondary prevention, it was a class one recommendation for six to move detection from six to 12 seconds or 30 intervals to reduce total therapies. Also there at the bottom, adding discriminators above 200 beats per minute to 230 beats per minute whenever, when appropriate. And for secondary prevention patients, because you have knowledge of the patient's clinical ventricular rhythms, this should enable you to have more information to appropriately program the patient regarding their therapy as well as discriminators and detection. Why did we need a 2019 consensus statement to follow up with the 2015 consensus statement? There were a few adverse events that happened, and it was because although we had these recommendations, manufacturer by manufacturer, when it comes to pacemakers, there's a lot of parity with transvenous pacemakers when it comes to programming. But when it comes to ICD detection, sensing, discrimination, there's a wide variance still. And so the 2019 document, in my opinion, if you're looking for a shorter document, is a better document to look at it because it goes by manufacturer, and this is a great summary of that document. So it's one page per manufacturer, and so I condensed that here. So Abbott Biotronic, Boston Scientific, Medtronic, I'm not going to walk through each one, but I'll point out a couple trends. The top portion listed there, these are your primary prevention patients that you do not have a history of a sudden cardiac arrest event, whereas the lower row there, these are your secondary prevention patients that you do have a documented ventricular event that you can utilize. And the difference being in the VT zone, in the primary prevention patients up top, you're picking an arbitrary rate that has some clinical data to support it, whereas in the bottom for your secondary prevention patients, you should have a rhythm that you should be able to pick 10 to 20 beats per minute below that clinical VT rate. So issues that come up with patients. There are patients that are in our clinics that have inappropriate therapies, and we can classify those inappropriate therapies as one of two categories, misclassification, so the rhythm is classified as a ventricular event when it's a SVT event, or a SVT event when it's a ventricular event, and under-detection, so delayed, the patient does receive therapy for a clinically significant event, but there's a delay to that that's unnecessary. So I have two case studies, one for misclassification and one for under-detection that were published that I found. So BARA published in India this case study here where it's looking at a Abbott device, and we noticed that single chamber, although its morphology is a match to the intrinsic, they have morphology onset and stability on. Onset and stability both were positive for this rhythm should be treated. So even though morphology was a match, this patient ultimately still received inappropriate therapy. From the manufacturer, most discriminators are on, and so as clinicians, you'll oftentimes optimization looks like turning a discriminator off or modifying what's already been on from the manufacturer. A classic example as well, if you have a patient who's complete heart block, you do not need discriminators turned on at all. So a standard, and this is recommended in the guideline documents, both guideline documents, is from the manufacturer in a complete heart block, pacemaker-dependent patient, turning discriminators off. It's going to unnecessarily delay time to therapy. For under-detection, here is an example in a patient with sarcoidosis. So this patient, even though V is greater than A, their ventricular rate is much greater than their atrial rate, and this patient, because of the sarcoidosis infiltration in this patient and the scar, there's quite a variability in the cycle length of the ventricular tachycardia. So stability voted that this rhythm should not be treated. Unfortunately, the patient did receive therapy, but therapy was delayed, and this is something that contributes to patient symptoms, including syncope. All right, so that is a lot, and just barely scratching the surface, so some considerations and best practices. In a post-simple trial world where patients are not having defibrillation threshold testing, that was an opportunity for clinicians and manufacturers to optimize a patient's settings out of the gate with a proven treated incidence of VT and VF. Now in a post-simple world, their first true test is likely going to come across your remote monitoring screen, or you're going to see them in clinic. So every episode with therapy is an opportunity to optimize a patient's device. Discriminators are nominally on, out of the box, so if misclassification or under-detection occurs, you'll need to consider which ones to modify or turn off. This is a complex topic and is very challenging to be an expert on all discriminators and detections for all companies, so utilize your local manufacturing representatives and tech services. These are my references, and thank you very much for your time. So our next speaker is Tammy Myers-Laplace. What drew Tammy to electrophysiology wasn't just the rhythm of the heart, it was the thrill of mastering its endless complexity. With over 15 years of clinical experience, Tammy thrives in the details of the heart's electrical system, finding excitement where others see only patterns. Today she brings that same energy and passion to the conversation, ready to dive into the nuances that make electrophysiology endlessly fascinating. Hi, everybody. I know it's afternoon, so halfway there. So I have no disclosures for this talk, and I think the theme that's going to be consistent for our panel is the fact that we do not have enough time to really get into the details. So my particular segment, we're talking about optimizing CIEDs, and I'm going to transition from this slide, and I have two very simple learning objectives. We're just going to review the functional need to have optimized programming, and we're just going to gain a little bit of insight on some of those algorithms that are available based on manufacturers that we can use, some of those tools. So what do we know about our patients that have CRT devices? What we know is patient selection is very important for the success of this therapy. We also know that lead location and placement is also very important to following up and trying to optimize these patients post-implant. The other thing that's a really strong part of our reality is how many patients are non-responders to CRT therapy. If somebody says, I have a 30% chance of doing anything, that doesn't sound very great for a surgical procedure or any type of intervention. And the other factor that we definitely know is that our patients usually require some type of optimization after their device has been implanted. So I have a question for you. In your current practices, what is your timing right now for any type of optimization? And I know this is a balanced question because we have a lot of new algorithms that are on and programmed on on the device that we utilize. I can do it either way. We can do the poll. We could do raise of hands if that's easier. So how many people for that four to six week mark? Okay. 10 to 12 week mark. Okay. 12 to 16 weeks. And those that fall in the bucket, well, I only touch it when I think it's broken. All right. I don't think any of those are technically wrong answers. So we're going to see what those that did the poll said. Okay. That is true to audience right there. Me personally in my practice, I think any of those time frames can work. Honestly, you may have to optimize your patient more than once in order to get it right. Our patients live dynamic lives. And when I met you, you may have not been doing so great. And at that time, that programming was appropriate. And now it's been three months. It's been six months. It's been four weeks. And we have to do something differently. So we do know that there's the benefit of getting our CRT devices optimized. And that definitely includes us really trying to get to the objective of having responders. Responsiveness in my opinion looks very differently. So the data says it'll be great if you have an improvement in your EF. I have not really seen that staggeringly in my practice. It'll be great if your patients have just better everyday function. If you're able to walk to the bathroom without having shortness of breath and other kind of symptom management things. So sometimes it's the balance of what we're doing, clinical presentation versus what the patient is able to achieve in their life to really say, yes, I have a responder. It's some type of improvement from their baseline. Some considerations as we are optimizing devices in our individual practices. Most of the times when the patient comes in to the clinic or you're seeing them in the hospital because we're having a exacerbation of some sort, our patients are laying down. They are sitting down. They are not living their best lives the way they normally do while we're making programming that's gonna affect them throughout their patterns of life. And then we added to the mix all of this very nice new physiological pacing. So we got really excited when we had our HIS bundle pacing to kind of achieve some of that CRT instead of just a traditional LV-CS leap placement. Then we got LEFT bundle pacing, which is our new hot topic. We love it, don't we? Mm-hmm. And then you have pockets of practice that are now combining all the forces together. So now we have things like HOT-CRT where we're doing HIS bundle pacing and still a CS lead. And then you still have your LOT-CRT, which is the same concept with your LEFT bundle lead and your CS lead just to try to help us gain some of that synchrony in our practices. So think about that. Think about your lead placement. Think about objectively, what can I do with a lead as we are considering how to best optimize the programming. This slide is busy, and it's also not a complete list of all of the tools that are available across manufacturers. Programming our patients are in part based on the algorithms, in part based on our understanding of physically where the lead is, as well as really understanding some of the limitations. Sometimes some of those vectors don't work. We don't have great capture, even though location-wise it is perfect, but it doesn't work. So we have to do something differently. This is also something, I think, for me, it's really remembering that if you come across a device that's not one of the newer devices that have some of those brand new spanking nice algorithms that we like, sometimes you just have to go back to programming negative hysteresis rates and really trying to leverage some of that additional programming. Checking your vectors, rechecking your vectors, especially if you initially check them closer to the time of implant. Sometimes when things settle, they get a little better. So that might be a good time to kind of reassess as you're doing your reevaluation for optimization for these patients. You have other tools in your basket. EKG, fairly available. Sometimes depending on how your practice is set up, coordinating might be a little challenging, but that's the same to be said for your echo tools. We have all done those nice hallway walks or stair walks to capture things with activity for our patients. And then you can also still use modalities such as like treadmill stress testing and those other options. My lab personally does not do that electrical mapping for dyssynchrony, but I do know that there are some pockets that are doing that just to help with some of that CRT optimization. So they're taking them back to the EP lab and really mapping and trying to get that done post implant. All right. So lots of considerations when we're thinking about what our optimal settings are and whether or not we're achieving what we want to achieve when it comes to our CRT pacing percentage. So I have a quick case study next and we'll just go through that. So this was a patient that had a dual chamber ICD that was implanted back in 2019. His EKG at the time had a PR interval of about 200 and a QRS of 176. This is a normal EKG with just some left bundle. Patient also had an echo done back in January of this year. And we did notice some changes on that EKG. I mean that echo. And one of the changes was his EF is now 13%. This is his correlating EKG. So just that baseline we can see now our PR interval is a little bit longer. It's 192 and the QRS is now 208. Definitely a more wide QRS than initial. So this patient did go ahead and get an upgrade to a Bybee device. And he did have a CS lead placed in the posterior lateral branch. So the device type that this patient actually got was just the Abbott, the Gallant, the HF device. And this is what he looked like immediately post-procedure or one day post-procedure. So question for you. Is there room for improvement? And I won't let the timer go down. I'll just, I'll take a out loud yes or out loud no. All right. So yeah, we made some programming changes for this patient. So his device was programmed this way. That's how his programming was set up. We went ahead and just used some of those algorithms in his SyncAV plus to just see where we were going, what we needed to do for this patient to see how we can better optimize where that QRS duration was. So when we put it in, especially for this manufacturer, you go ahead and you run those algorithms, it gives you all of the measurements. So this is exactly what it measured, what it looked like, where we were programmed and what the device said was optimal. So you'll see for our PaceAV delay, we were programmed at 200, the device said 150. Our sense was 150 and the device said optimal was 100. And even from the intraventricular programming aspect, we had it LV equals to RV for the pacing, but the device said what was optimal was 45 milliseconds LV before RV for this patient. This was his post EKG that was finished after we finished making some of those programming changes. So no significant change in the PR, which is appropriate, but that QRS duration went from, his very first original was 208, if I remember correctly, and then the other one was like 190 something. And now we're down to 174 and that QRS looks pretty skinty. So it's not always big changes that we have to do for our patients. It's not always long walks. It's not an hour of trying to troubleshoot. Sometimes the key is really just identifying early that we have to make some change and modification for the patient. Starting small, making those changes, seeing what happens from the impact, and then using your data from your tools, your EKG, your echo, and then asking the patient if they are doing or feeling any better after those changes. Thank you. Thank you so much Tammy, that was great. And I'll introduce our next speaker, we've left a little bit of time. Dean Engel is going to present on rate response programming. Dean has worked at Mayo Clinic in Rochester, Minnesota for 29 years, 7 years as a health and fitness specialist in worksite health promotion, 8 years as a cardiac nurse in hospital based bedside critical care, and the last 14 years as a cardiac device nurse in heart rhythm services. Dean holds IBHRE CCDS certification. Thank you Dean, take it away, I won't take another second. Alright, well, I want to really, first of all, thank you guys on such a big event like this that you chose to share this time with us at this session, I'm so grateful for that. And my hope is that I can teach a little something here in the short period of time that I have to cover all different devices and to somehow make this meaningful. I would like to, just a real quick note, is how many people here are device nurses, device techs, or have hands-on with programming devices, yes, and APPs, and they may be kind of already, and then physicians? Alright, well, this is my people right here, thank you very much. So our learning objectives, talk about chronotropic incompetence and talk about the different rate response modalities and the differences between the companies, as well as how to assess for the data and what to do with the data that we get. Chronotropic incompetence, so it's the inability of the sinus node to be able to give the person a heart rate that they need based on the activity or the metabolic demand at the time. So this is common in patients who have cardiac disease, also it's an independent predictor of major cardiac events and overall mortality, but most importantly, it produces exercise intolerance and poor quality of life. And the most commonly used definition in literature is failure to reach 80% of expected heart rate reserve or 85% of the expected kind of age-adjusted heart rate response. The physiology review, so the heart rate in beats per minute, stroke volume, the amount of blood that's pumped by the heart with each beat, and then the cardiac output, that's a product of the two, it's the volume of blood that's pumped by the heart over each minute, stroke volume times heart rate. And the stroke volume plays an important role more at the beginning of activities or exercise or the metabolic event that's going on, and it may improve by 25 to 50%, whereas a heart rate response, an appropriate heart rate response, can give us an increase of up to 300%. And so how do we calculate the heart rates? How do we know how much or how high a person's heart rate should go? And most of us, I think, are familiar with the Fox formula, or in the exercise science world, we call this the Fox formula, 220 minus age, it's easy, it's kind of a quick reference. This really, on its own, is more for people who are more athletically fit or younger populations. So we correct for that by taking 85% of their calculated age predicted heart rate maximum for people who are 50 years older and more average activity. So what does this look like when we're thinking about, okay, what is a reasonable heart rate for like a 70-year-old adult in this example? So 220 minus 70 is 150, 85% of that is 128, and I think for most people, that 70-year-old, kind of that out-of-box nominal implant programming, DDDR, 60 to 130, makes sense. And if you were to have an 80-year-old, this same formula comes down to 119 or 120 would be our maximum heart rate. So why be active? Why are we concerned with our, well, for all of us, really, to be active and exercise and be able to do those things on a daily basis, reduce mortality, reduce hospitalization, improve our quality of life, improve people's heart failure class, and improve other hemodynamic measures. And how much exercise should our patients be doing? Again, this is a good time to also think about us. How much exercise should we all be doing? It's a challenge for everybody. So to get at least 150 minutes per week or 30 minutes on most days of the week of just moderate intense physical activity or 75 minutes of more vigorous or higher intense activity, and that'd be like 25 minutes a day, three days a week. And then for people that have the resources and the interest to add some strength training to that, but bottom line, just be more active. Help our patients think about, can we park farther away? Can we take the stairs? Can we stand instead of sit in certain situations? Things that might just keep us active. And as they're becoming, I think, more interested in activity and kind of more physically fit, maybe to go up as high as 300 minutes per week for those that can and want to. So what does this look like when we think about the scale of just being from being rest up to our kind of our maximum more intensity exercise? Because sometimes you're looking at the data and you're wondering, I'm not really sure how high my patient's heart rate should be getting with certain activities. So when you look at very light to light, kind of that 57 up to 63%, 90 to 100 beats per minute is reasonable. The basic activity of daily living that they might be doing from walking around, doing light housework and so on, excuse me, moderate activity that more of the, you know, brisk walk, the yard work, some light housework, maybe taking the stairs, you're starting to get 100 to 120 beats per minute. And then for the more intense, you know, kind of formal exercising, whether it's hiking and biking and running, jogging, get up near 120 to our maximum, up to 85% of our maximum. And then for people that are more physically fit, you can kind of see, we can really start to push those boundaries for certain patients that really need that heart rate response up to even 150 for this 70 year old. All right. So how do we know if our patients need rate response programming? Most importantly, talk to your patient. And what we've talked about, I mean, I think the consensus is with all of these, we're all challenged by having enough time, right, time and resources to be able to spend with our patients. But to somehow start teasing that information out as you start to interrogate the device, how do you feel with activity? Are you able to do what you want to do? The device has data within it, like histogram data, a 24 hour heart rate sensor response. If they're coming to see us, maybe they're also having their annual cardiology follow up and they might have exercise stress test available or a halter monitor available. So you might have some data also at your disposal there. And then in today's world, many people come to us and say, my Apple watch or my smart watch is telling me, or I've got all this data collected when I go for my bike ride, my heart rate's only getting up this high. So that can all play a role to kind of help us understand our patients a little better. For those that haven't, you know, we've all seen the histogram data and you just kind of know it when you see it, when you see somebody who's got really blunted and kind of limited histograms. But there's also a validated method called heart rate score. And that looks at long term heart rate variation. So it's defined as the percentage of all atrial, paste and sense beats in the single tallest 10 beats per minute bin. So it's the height, your heart rate score is the height of your tallest atrial bin. So of course, we want people to have a more robust or more wide range distribution of the histogram. So therefore, you would have a lower heart rate score. If you see somebody who has a heart rate score of greater than 50, if they're not already have rate response on, you should be thinking, do they have rate response on? Maybe you start engaging that conversation. And if you see a score greater than 70%, that also comes with a higher risk of complications with morbidity and mortality, especially combined with other clinical findings. So what does this really look like when we're looking at it? So for example, I think you know it when you see it. If you saw this on your histogram, at 96, you probably would start asking the question, are you able to do the things you need to do? At 80, you can start to see the shift as it starts to come down, and here's 50. So this one, you'd probably say, not so bad, but maybe we'll just talk about it a little bit. Are you able to do what you need to do? And this one being 38, probably have very little concerns with that. All right, rate responsive pacing. So the sensor must detect a physiological parameter based on metabolic demand. And the device has to have an algorithm that's linked to the changes in the sense parameter and the change in the pacing rate. And because each patient's different, the magnitude of changes of their activity and the device and the different algorithms, they're relying on us to be smart enough and aware enough to be able to program the device appropriately to really make sure it's optimized for them. So there's different types of sensors. We've got the activity sensors, the motion sensors. And most of today's devices are the piezoelectric accelerometer, and they're actually a hybrid of the two. So it's both vibration as well as kind of the movement in the geometric plane. And then we're not gonna talk about the leadless pacing, where the micro has kind of multi-axis. And then there's the physiologic sensors. The breathing with the minute ventilation, the ventricular contractility with closed loop simulation, and then the Avidivir relies on temperature changes. So programming the rate response, slope and aggressiveness, sensitivity, and then reaction time and recovery. So we'll focus specifically on slope and sensitivity. And bottom line is all the companies are a little different, so we need to kind of understand the different terminology and algorithms and the directionality of these devices. So with Avid or St. Jude, this accelerometer, and the two things here we'll focus on is the threshold and slope. And the threshold is the amount of activity needed to initiate the sensor, so it's really the sensitivity of it. And it's programmed from one to seven, with one being the most sensitive. And it can be set to auto, anomaly is set to auto. And with all these devices moving forward, I really encourage you to keep these devices on auto settings, unless you need to program off because the person is presenting to be a challenge to really optimize them. So with the Avid, it measures variations over the last 18 hours, it adjusts the threshold automatically, and it will actually display what's called the measured average sensor value. And if you haven't really noticed it, maybe you now will after we've talked about it. And then we can program the offset values, it can be programmed for more fine tuning. And you see on there it's, where it's minus .5 plus 0.0, which is the anominal, plus 5, plus 1, and so on. So, and you see right there is your measured average, and then plus. So if my measured average is 2, plus 0 means it's just going to keep it at 2. Pro tip with the Avid, if you're just looking for something to do that's just kind of the best bang for your buck, without really changing too much, and you want to make it a little bit more sensitive, go to minus 0.5. And that will basically turn that 2 into a minus, or into a 1.5, and I'll show you what that looks like. So you can see right here is, so the average here is two, and then if I go minus 0.5, then it will make it more sensitive here at 1.5. All right, and then the slope. Slope describes the sensor-driven pacing for a given level of activity for the level of response, and this is our aggressiveness, from one to 16. So this is kind of inverse. 16 would be the most aggressive, and one would be the least aggressive, so. Bottom line is, so it's based on recent activity levels, just like threshold. It's constantly evaluating and adjusting. Offset values can be adjusted to finer tune it. So keep it on auto, and you can adjust. So the typical setting is here. You'll see is, oh, well, we'll go there, okay. So you can kind of see right here is that this is how steep 16 is, and you're one. So measured auto here is eight, so it's right down the middle, and then a plus two would jump up two, so it'll say, oh, that I'm now going to give it a 10 to make it a little bit more aggressive. Biotronic, closed-loop stimulation. So when the body is telling us that we need more cardiac output, right? You see kind of right here. The body's saying, hey, look, I need more cardiac output. It's telling the heart, beat faster, beat stronger. And then you can see when we lose that sinus node, the myocardium now has to work a little harder, and the device can now take changes in the ventricular contractility and the inotropy to say, oh, I can use that same change in the myocardium and now equate that to a faster heart rate response. So you can see right here is when the heart is more at rest or diastole, you'll see that there are less surface area around that lead tip and more blood volume. We're gonna have a lower impedance at that pre-ejection, and then with that contractility, you'll see now there's a greater cardiac myocardium around it and less blood volume, and now I have a higher impedance. And what does that look like? So the first five minutes when you turn it on, the device is establishing all these coarse waveforms, and we're only really going to achieve 60% of optimization when I turn it on. And it's gonna get one reference waveform for each phase of pacing, so apace, vsense, apace, vpace, asense, vs, and then asense, vpace. And then you see right here, this is actually one cardiac cycle. So that would be like the P wave, the QRS, and the T wave. And you'll see right there, there's eight biphasic pulses on there. And basically, it figures out, this is my waveform at rest. It knows when the accelerometer's moving, my person is at rest, I'm going to keep looking at this waveform. It's very similar to like, for those of you that are used to working with defibrillators and you look at like morphology matching scores for like ICDs, this is kind of the same thing. It knows when there's activity and the contractility changes, the waveform changes, and it will use that percent of change as it knows this is not a match anymore. There's something different going on. But to go back to that real quick is, it takes a full week. So if you turn it on and expect immediate results, just know you're not going to. You're gonna have to give that person time and for it really to be optimized. And this is what this CLS response will look like. You'll see very low is the least aggressive, very high is the most aggressive. So right here, you'll see our, well, I'll just go right there. So 21% rate of change plus the base rate up to 51% rate of change, the baseline. Again, way just to keep the device on its own automated programming. All right, minute ventilation with Boston Scientific. Again, Boston Scientific and Biotronic both have the accelerometer where we're gonna focus on the features unique to them. So with minute ventilation, it's able to look at thoracic impedance and how it does that is using Ohm's Law, it's delivering 320 microamp pulse every 50 milliseconds all the time from the ring to the can across the thoracic cavity. And then we can measure voltage from the tip to can. And as the patient breathes, it's able to measure the transthoracic impedance and with that, it knows the respiration rate and the tidal volume. So we can see is that respirations are picking up and a person has a greater metabolic demand with the exercise or activity. All right, so two things with the minute ventilations is looking at your long-term baseline and your short-term baseline. The calibration, when you first add implant, you connect the leads, it takes about six hours. But if you were doing a pack change or just wanted a more immediate sensor calibration, you can do it within five minutes by telling the device to do that. And that long-term baseline is adjusted every four minutes. And then it compares that with your short-term average. And the short-term average is every 30 seconds and it actually has a rolling 7.5 seconds within that. So there's four rolling 7.5 seconds within that short-term average. So if you look up here, you'll see the solid line is your baseline and then the more jagged line is your short-term average. And then using this scale, you can see, wow, there's a big significant change right there. So it says, okay, our thoracic impedance is changing and increasing. So we can now program the response factor. And the response factor goes from one up to 16, so with one being the least aggressive. And then nominally out of the box is eight. So you'll see right there, your sensor indicator rate is your lower rate limit plus, the response factor number we've chose times the change in minute ventilation. So the higher the number, the greater multiplied response. Minute ventilation does work. It takes time, especially for your more active patients. All right, Medtronic accelerometer. So with the Medtronic accelerometer, you can program your threshold here from low up to high. So most of today's current devices have a nominal setting of low. The older ones are medium low, but it really doesn't matter. If rate profile optimization on the device is gonna figure it out. So don't hesitate with staying with the current low or when you're doing generator replacements. But the accelerometer signal's processed into an activity count based on the number of threshold crossings and the relative magnitude. So this right here, it's always looking at a two second burst and it's looking at how that accelerometer is changing. And so we'll do a quick count here. So if my threshold is low, it goes up and below. So we've got one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28. So there's actually 28 counts. Keep that in mind, remember that. It's always looking at those counts when we get a little further along here. All right, and there's two different values that you're aware of. There's the ADL slope and the exertion slope. The ADL slope is kind of right away in 30 seconds into an activity. It says, okay, there's something going on here. Let's get ourselves up to the ADL rate and then we'll hit this plateau. And then as the intensity increases, we'll reach up towards our max sensor rate. So, and the activity counts you'll see listed here as an example are 18 for ADL rate. So it takes a lot less activity to get to the ADL rate versus your exertion rate is up to 40. Rate profile optimizations on and keep in mind that out of the box settings are really tailored towards a 65 to 75 year old person. So your ADL rate and your exertion rate are programmable with one, two, three, four, five. And you see that out of the box you've got, they're always programmed at three and the higher up you go, the more robust the shift is in your histogram response to the right. Same with exertion response, more on the tail end as you start to hit the max sensor rate. All right, so but what does this even mean? What do these numbers really correlate to? And believe it or not, it actually refers to the time of day towards the ADL rate. And keep in mind when we talked about the American Heart Association guidelines of 30 minutes a day on most days of the week. And really this falls right into that. So the target profile, so three, it would be 30 minutes per day and on the exertion value would be three minutes a day. It's just saying, it doesn't matter how active my person is it says I only have so much time that I can really give you. So talk to your patients, find out how active they are and you can adjust these numbers. And by adjusting the numbers, the device will auto make it more sensitive and auto make it a little more aggressive as it needs to. All right, but the bottom line is, and this is what the take home point with this is, if you have a patient that gets at least an hour and a half a day of most days of the week, that's when you should consider turning off rate profile optimization. Because even at five, it's really not doing the job for them and I would also encourage you to talk to your Medtronic rep or call the Brady Tech people and as you're starting to go outside of that and take rate profile optimization off, but realize it's probably not gonna meet their needs. So make changes one at a time. Make sure you're evaluating these changes right. Go take them for a walk. Our programmers are becoming much more portable so we can take the iPad or the Boston Scientific programmers with us and actually walk with them down the hallways or up a flight of stairs. I like to actually take people to our cardiac rehab area. They'll usually let us use like a bike or a treadmill and I can see everything real time. And, all right. Well, take the time that you need to with these patients. Help optimize this and give them kind of that care that they need to really make sure they're living their best quality of life. All right. Thank you. Thank you. Thank you so much. Dean, that was really great. We do have some questions and we've got a few here that Chris will take and then if anyone wants to go up to a microphone, we know we went over by a few minutes, but we do have time for questions. So, thank you. So, Tristan, I think the first one is for you. So, can you explain what you mean when you say discriminator? Discriminator? So, one of the algorithms that discriminates between a supraventricular tachycardia from a ventricular tachycardia. So, the ones that were listed, onset, stability, morphology, V greater than A, PR logic is one that kind of falls into a pattern category. SVT, rate threshold. These fall into the ICD discriminators that help the device decide whether or not it's a supraventricular tachycardia from a ventricular tachycardia. And whether or not to withhold therapy or to deliver therapy. Tammy, we've got one for you. So, how often do you use adaptive algorithms? There was latency to capture in the case you had showed. Baseline ECG looks the same. Okay. So, when I decide when, what's the question again? When am I gonna? So, how often do you use them? And then, there was latency to capture in the case you had shown. Baseline ECG looks the same. So, we decide on whether or not we're gonna use them. Sometimes, I will tell you, in the lab, we will compare what we find in the lab to where it lands on auto. So, if at initial implant, that's not the right time, then we go back and we really try to correlate that with what we're seeing. So, if what we're seeing, we compare it to the auto algorithm, we will run all of those tests manually. We will redo them, look at them through EKG, look at the latency. For that particular patient, that wasn't, we didn't feel like that was a time to address that with the patient, and that's the reason why we didn't do it. We have a plan to see this patient back again. He lives far away for our practice. So, we are actually gonna see this patient back at the end of May, and we're gonna try to optimize him more. He was not finished. Yeah. And Dean? Why not have rate response turned on for all patients? Okay. Well, I think, I mean, I think that is reasonable. I mean, it typically is not gonna be harmful. For some people, it does complete, kind of compete with their sinus node for people who have a normal sinus node. But I typically wait for the patient to tell, I mean, unless I otherwise really don't know, but with patients with complete heart block with no known sinus node dysfunction, no complaints previously, I'm going to keep it off. But I don't think it's bad or harmful to turn it on with all patients, just so it's kind of there if needed. Because people do change over time, whether it's the medications or the cardiac disease process. And so it's, sometimes people just need it. Maybe they had a device, and it's not five, 10 years later that it starts to happen. And how do you feel about the blended Boston Scientific Sensor? Well, I'm a fan of it. I know that when you're dealing with a person maybe who's 70, 80 years old, and they're just not getting the heart response because maybe the rep turned just minute ventilation on, only an implant, and it's just not working, and you only have so much time. You say, I turn on accelerometer and turn minute ventilation to passive, and they're off to the races. I mean, and now it's actually working. That's a quick, easy way to do it, but minute ventilation and blended does work. But for my more advanced patient, it does take time. I need to get them on a treadmill or a bike or something. Okay. And that's why mine went over, because I know I can't do it. It's just the mic. Hi, just a quick question for Dean from Children's Hospital of Pittsburgh. We've been using the Medtronic rate response, but we typically see that we need to have it on for our patients, but they're constantly noticing the increased heart rates when they're driving down a bumpy back road or they're on the school bus, and they're extremely symptomatic with it. We've been adjusting slopes and adjusting their sensitivity, and they're still reporting these symptoms. Do you have any recommendations on getting around this? No, that as soon as people call, and they say, either I'm out on the boat or I'm driving down my country, I know exactly which device they have, and it is one of those true limitations. Because as soon as you make it less sensitive, now it just doesn't respond when they actually need it. But so it's a balance of their quality of life. So it really is a limitation of the device, and I wish I had a better answer, but it truly is. Thank you. This is just a question in general for the panel. So my site covers a lot of patients that live three, three and a half hour drive from our location, and we don't have any remote device clinics set up. What's your take on how you optimize those settings for patients who can't easily make a trip back, even monthly for those adjustments based on distance? Personally, this would probably be one of those exceptions to the rule. Typically when we make programming changes, we like to do them one at a time. If distance is a limiting factor, sometimes I may try to tackle two things, just very small changes at a time. And if it's not intrusive to their life, then I'll schedule it out when they come back. So if that's six months, then that's six months, and they'll kind of live with it. Or if it's really bothersome, they tend to want to come back to have that optimization. So I try to work with them as much as I can, but it's really up to the patient to decide how comfortable or uncomfortable they are with their programming so that we can fix it. For sure. I'd like to add something to that. One thing, I love rate response programming, too. And I would often, if I knew a patient was coming in for that, I would schedule them first thing in the morning, and then I'd send them out for a couple hours and say, okay, go take a walk. We have a beautiful nature trail here. Find some stairs, let us know how you feel. So that if we needed to see them again, squeeze a minute lunchtime, see them again at the end of the day before they're driving six hours away, we have that opportunity to make sure we didn't make anything worse, and that hopefully we've made things better. Okay. There are more questions. Okay, well, so yes, that was me. I let the timer go a little bit longer. So we do have a couple more questions. We have another minute, and then I know our speakers would be happy to stay after and answer any additional questions. So do you wanna do the ones on the iPad then? Yeah. And then people in the, oh, okay. So how do you treat patients that would likely benefit from rate response based on histogram data and activity level that just don't like the way it feels? Well, I mean, that is, I guess, a challenge. It just would, you have to get them on a treadmill, get them on a bike, or these are the things, or whatever activities they like to do. But to somehow, I guess, thread that needle of making sure it's not crossing over into other activities where all of a sudden now they're just washing the dishes or changing their clothes and their heart rate starts to go up. But, you know, I guess that is a hard one. And every once in a while I do run into that. And part of that is adjusting the program because I guess I think I can fix it. And that's, if you know me, then I'm the guy who says, no, I know I can do it. So you, if I, I'm gonna give you the time you need. So it's not, you're not going to be so uncomfortable with rate responsive pacing. So we'll send all our patients to Dean. Yeah, I mean, really, because I just, I guess if I hear that, I'm immediately gonna think, no, I'm the one that can fix this. We do call Dean our rate response guru. Yeah, because it's probably just too aggressive, is what I would say. There are a couple more questions here. Does a more narrow QRS always equate to better outcomes or improvements in symptoms? No. My short answer to that would be no. Just because you have a narrower QRS does not equal, it's not equal. The idea behind the narrow QRS is really, I think, to activate the normal intrinsic conduction system to kind of take away from those long-term effects that we know happen to our patients that are, let's say, RV pacing or things like that. So short answer to that is no. It's just one of the tools for us to look at and help paint an overall good clinical picture of our patient along with their patient history or story. It's an easy kind of quick way to at least predict a little, you know, some success. Especially for us as device professionals because I'm not doing an echo or anything, but I can at least get a 12 lead and do that. Okay, great, thank you all for attending. We really appreciate having you here. And if you have more questions, just come on up. Thanks.

Heart Rhythm 2025

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