Dr. Iyer discusses the patient selection process and implant procedure for the Aurora extravascular defibrillator.
Good morning. Uh, my name is Venat Eyer. I'm one of the cardiac electrophysiologists here at Norfolk, and today's grand round's topic is gonna be, uh, related to advances in ICD technology, and I'm gonna specifically discuss the Aurora extravascular ICD system. Uh, during this, uh, 40 minute talk, we'll talk about a few things here. Uh, number one, we'll discuss ICD indications. Two, we'll talk about patient selection for this device. Uh, we'll talk about the clinical data review of both the pivotal study as well as the, uh, the post approval registry data. We'll talk about the implant procedure and then we'll talk about future directions with this technology. So ICDs have come a long way. Uh, initially when we had the, uh, initial generation of ICDs, these were all, uh, uh, epicardial ICDs, uh, then moved to transvenous ICDs. The indications therefore have also increased considerably, but our major indications, uh, these days are still primary and secondary prevention devices that we put in. Over 85% of our indications come from here. So primary prevention, you have both ischemic and non-ischemic cardiomyopathy. And that is, uh, the magic number for an LVEF is about 35%. They have to have some sort of New Yorkers Association functional class, either 2 or 3 symptoms, and they have to have guideline directed medical therapy. Uh, if you have an LVEF less than 30%, uh, a New York Heart Association functional Class One statement, again, the same timing requirements will, will be, uh, will be there when you look at secondary prevention, uh, uh, so primary prevention for non-ischemic cardiomyopathies, again, the EF requirement there is 35% or less, uh, and the expected survival has to be more than 1 year with greater than 3 months of optimal guideline directed medical therapy. Uh, ICDs can be indicated even with patients with preserved EF. So for example, if you have hypertrophic cardiomyopathy patients with high risk features, so either prior VT or EF, a family history of sudden cardiac death, um, LDH, uh, greater than 30 millimeters, uh, or syncope suspected to be arrhythmic, an ICD may be indicated. In addition to that, you have other special situations where you have ARVC patients, you have long QT syndrome with syncope, despite beta blockers, Brugata syndrome with, with syncope or VT or VF, and CPVT. So these are some of the cases in whom we may consider putting ICDs. Uh, again, other specific special indications would be in, in post MI patients, uh, who have some sort of LV dysfunction. They don't meet the 35% LVEF criteria, but they have inducible sustained VT or VF on an EP study. This was sort of the must comes out of the MUS trial that was done by my mentor Al Buxton. Um, you can have patients with sarcoid, amyloid, or other infiltrative cardiomyopathies, uh, who have higher VT risk, and then you have congenital heart disease patients with sustained VT or high sudden cardiac death risk. So again, pretty wide variety of ICD implant indications that have that have that have sort of been been carefully crafted and adhered to pretty carefully over the last 15 to 20 years. These are patients in whom you should not implant an ICD. So if you have a reversible cause, so somebody with an acute MI within the 1st 48 hours, an electrolyte abnormality, a drug toxicity, if they have end-stage heart failure, they're not really a transplant or VAT candidate, if they have a life expectancy less than 1 year or they have heart failure class 4 despite optimal medical therapy unless they're a bridged to advanced heart failure, please do not call us to put an ICD in them. These are, these are exclusions to ICD criteria. So the question then becomes why do you choose EVICD or subcutaneous ICD instead of a conventional transvenous ICD and so you have to consider the patient. So if you have a young patient, so a 35 or 40 year old patient with Brugada, let's say, who has had syncope, who needs an ICD, putting a transvenous device in them may be problematic, uh, because you want to avoid transvenous leads, you want to preserve the venous system. Uh, they may be patients who've had infections on both sides, uh, both, uh, both, both, both sides, and so they may be a high infection risk, or you want to avoid valve damage, so tricuspid valve, so these transvenous leads go through the tricuspid valve, and avoidance of tricuspid regurgitation would be a good reason to choose an extravascular ICD or a subcutaneous ICD. So what is a subcutaneous ICD? Boston made this device. We've had this for about 10 years now. It's a totally extrathoracic ICD system. The generator is here as you see my cursor here. It's in the left lateral thorax, sort of in the mid axillary line. It's a pretty big device. The lead is then tunneled into the sort of into the into the sternal area here, and then it is put subcutaneously sort of parallel to the sternum. So what you have done here is this is a completely extrathoracic ICD system. you don't have any transvenous leads. You don't have any intracardiac leads, and so you spare the venous system as a result of that. So this has been there, uh, I want to say since 2017, 2016, over 100,000 devices have been placed, uh, worldwide with, with very good results. This is an extravascular ICD. This was FDA approved last in the last couple of years. Uh, it's made by Medtronic. Uh, the name of the, the name of the generator is called the Aurora EVICD generator. It's the same generator size as a transvenous, so that's one of the advantages over subQICD where the sub QICD is significantly bigger generator size. This is a much smaller generator size, and this is the lead. And the difference between this and the sub QICD is the lead is truly substernal, so you have to place this underneath the sternum, not above the sternum, not to the side of the sternum like you place for subQICDs, but actually underneath the sternum. So you have a pectoral generator, but you have a sub substernum. Leads and again we'll talk a little bit about implant procedure here, but this is the epsilla lead that sort of has an epsilon shape here. These are the coils, uh, defibrillation coils, and these are the sensing electrodes. So you have two sensing electrodes and two defibrillation coils. So then the question becomes, why do you choose an EVICD over a subQICD? And the biggest advantage here is the ability of the EVICD to have anti-tachycardia pacing. Anti tachycardia pacing is very, very important. The reason it's important is because, as you will see in some of the data that I present later on, if you have a patient with sustained VT, you don't necessarily want them to have a shock. If you can suppress the, if you can terminate the VT using anti tachycardia pacing, you've basically helped the patient avoid a shock. So anti tachycardia pacing is the biggest advantage of this device over the subQICD. The second device, the second advantage is post-shock Brady pacing because this lead is in contact with the heart, you can give pacing. So if post-shock they have bradycardia or or they have asystole or something else that you can potentially give them post-shock bradycardia pacing. If they're having pauses for some reason, you can give pause prevention pacing. Uh, the defibrillation threshold for a subQ ICD is 80 joules. This device is 40 joules. It's a standard transvenous ICD shock that you can give. Significantly smaller device size, and the battery life is about 11 years compared to 7 years for a subQ ICD. So, so things to consider when you see a patient in the office, when you see a patient in the hospital, as to young patient meets criteria for an extravascular system. Should they get the EDICD? Should they get a subQ ICD. So this is the lead, uh, it's a pretty nice lead. uh, it's, uh, it's, it's got, like I said, two coils here, two defibrillation coils here, two sensing electrodes. It has an anchoring sleeve, and then it's an EV4 connector that goes into the, into the, into the regular transvenous generator, um. And you have two different lengths for this. You have a 52 centimeter length and a 63 centimeter length, and this has dedicated use with the Aurora EVICD. This is what it looks like. Uh, this is what this looks like. You have the, uh, you have the generator sort of in a similar place as you would put a sub Q ICD generator here. It's not as posterior. You don't have to be as posterior as a subQ ICD. You can place it slightly more anterior so that when a patient wants to sleep on the left side, they don't have the generator there. Sort of in in their way of of sleeping on their left side, but the key difference is here that the lead is tunneled underneath the sternum rather than to the left or the right of the sternum in the subcutaneous space. So this is underneath the sternum. So that offers a little bit of challenge in terms of implant technique, but we'll talk about that in a bit here. So this was a pivotal trial that, that, that got FDA approval. It was published in the New England Journal of Medicine, uh, sort of led by Paul Friedman from Mayo, um, and, and, and, and Ian Crozier, who's actually a New Zealander from Christchurch. Uh, it was a prospective single arm non-randomized global study. 55 implanters, 17 countries, they attempted 3616 implants, of which 299 were successful, so they had a success rate of 94.6% of patients who were attempted got this system. When you look at baseline characteristics, the one couple things that stick out from this study is that the mean age of these patients is pretty young, it's pretty low, so the patients are about 54 years old, 25% of these patients were female gender. ICD indications again, if you count secondary and primary prevention ICDs, uh, these are about 99% of these were, uh, primary or secondary prevention. Uh, the patients were not, were, were, were had a BMI of 28. The mean LDEF was about 38.9. And again, when you look at the cardiomyopathy status here, uh, 72% of these patients were either ischemic or non-ischemic. There were a fair number of patients who had channelopathies and hypertrophic cardiomyopathy, so about 20% of these patients were non, um, ischemic or were, were not, did not fall in the categories of ischemic or non-ischemic category. Um Uh, one of the questions that they asked during this trial as far as safety was concerned was, was, was your risk of inappropriate shocks and uh. And and you had a 10% rate of a first inappropriate shock at one year, and the majority of this occurred within the first six months and we'll talk about why this happens. You want to prevent inappropriate shocks in these patients because of the risk of, you know, PTSD from shocks or or heart failure from shocks and things like that. And so, but the most common cause was P wave over sensing and as I present the registry data, we'll see how these numbers have come down significantly. But the major cause of this was PA over sensing. Remember that this is a pivotal trial. People are trying this for the first time. Implanters are all over the place. Uh, despite good training programs, uh, you're gonna see some of this stuff. So it was, it was about a 10% rate of a first inappropriate shock at one year and. Um, Medtronic now has a system called SmartSense, which is an algorithm that reduces P wave over sensing. So why does P wave over sensing happen? P wave over sensing happens because when you put this substernally, you have a right atrial appendage to deal with. And if the right atrial appendage is pretty big, then what ends up happening is you not only sense the ventricles, so you not only see the R wave, but you also see the P wave. And sometimes when you see the R wave and the P wave on the same electrogram, the device may get confused, and unless you have strategies or algorithms that can mitigate that, that may be considered, that may be double counted and caused and it may, may, may, may fool the device into thinking that you have VF and you may get an inappropriate shock as a result of that. So, so the most common cause was P-wave over sensing. And, and we have, we have some novel discriminators that have now been added to the software package for these uh for these defibrillators to, to sort of reduce that. Again, when you look at defibrillation efficacy, now this is in the lab, defibrillation efficacy on panel A here, you saw that 98.7% of patients had a DFT, so a defibrillation function testing, a DFT of less than 30 joules, which is like a transvenous ICD. So compared to a subQ ICD. Which is 80 joules and you have this ominous sound of, of, of patients, you know, the, the, the, the the device charging, uh, to, to, to, to get, to get a successful shock. The, the, the, the defibrillation efficacy here was pretty good. 98.7% of patients had a DFT less than 30 joules. When you look at freedom from major system or procedure related complications in panel B here. Uh, 92.6% of patients had freedom from major system or procedure related complications at six months. Again, remember this is a pivotal trial, so, so it's very important to see these numbers being high, um. Um, uh, to, to sort of assess safety of these, of these of the, of this device. Uh, again, from the pivotal trial, when you look at appropriate therapies here, you'll see here, and this is the key here, uh, 46% of patients had an episode of VT that was terminated by ATP, and this would not be possible in a subQICD because a subQICD does not have the ability to give ATP and so. You've seen here that 46% of of of appropriately treated devices were terminated with, with, with, with ATP, which is a huge deal. All of these patients in the if they had a subQICD would have received shocks. Here ATP was able to prevent them and and. Uh, 82 appropriately treated episodes in 24 patients. Again, here was the, uh, here was the total mix. So 12% of patients, uh, 12% of episodes needed both ATP and shock. 41.5% of patients, uh, of, uh, episodes, uh, got shock only, and then 46% of patients, um, had ATP terminating these, these episodes, which is, which is a pretty big number. Again, when we look at uh EVICD safety assessment here, it's 89% freedom from major system or procedure related complications at 3 years, which is pretty good for for brand new implanters. And again, the most common reason for a major procedure related complication was lead dislodgement, and I will tell you I went through some extensive training on how to tie leads um in in my training in Minneapolis, and they taught us this special knot called a constrictor knot that you need. To put down to make sure that this lead does not dislodge, and the reason for that again was because they had a significant number of patients whose leads weren't tied down correctly and so as a result of that they had lead dislodgements, um, so lead dislodgements, uh, there was obviously wound and pocket infections. There were some lead fractures and then others, uh, uh, interestingly enough, there was no cases of sepsis, endocarditis, or mediastinitis, uh, that were related to the EVICDs, uh. And so the safety was, was about the freedom from major system or procedure related complications at 3 years has been about almost 90%, which is a fairly, a fairly high number. Uh, what about removal? So for these patients that had, uh, that had, uh, uh, dislodgements and things like that, um, 93% of cases up to 3 years, the EVICD lead was just removed easily by just manual traction in most cases and, and really no complications, uh, were. We seen uh at all and again simple traction, but you could also use some telescoping tools like we use uh for laser lead extractions and things like that uh they needed to use a spectronetics tight rail sheath for a couple of cases, but for the most part manual traction just pulled the lead back and, and then you could go ahead and implant another lead if you needed to. So the implant process we'll spend the next about 10 minutes looking at implant process. Uh, patient selection is key here. Um, patient selection, younger patients, uh, patients that don't have venous access, uh, patients that have had previous infections, uh, patients in whom you think that their life span is gonna be pretty long, and the need to preserve sort of venous access would be good, patients who need an extravascular system but also need ATP, these are the patients in whom, uh, an EVICD system made by Medtronic should be, um, should be considered, uh, pre-procedural, you want to look at a CT scan. Assessing anatomy of the intrathoracic structures is very, very important. And so getting a CT scan of the chest or any CT scan that they've had in the last few years should be useful. If you wanted to get a cardiac MRI that may offer a little bit more detail, but we want to stick to CT scans. Getting a chest x-ray becomes important. You wanna coordinate with CT surgery. You wanna make sure they're available, so this has to be done in a place where CT surgery is immediately available. Uh, for the 1st 5 cases for a new implanter, a CT, CT surgeon has to be in the room scrubbed in with you. Uh, and then after that they have to be available in, in the, in the room, uh, general anesthesia obviously because this, this device, this lead is going underneath the sternum, it can be very, very painful, as I'll talk about a little bit later and so you want to make sure they have general anesthesia. You should have access to a TEE just in case you think you may have a complication or so. Getting having an echo probe that you can put down quickly to look at the cardiac silhouette and stuff like that becomes very important. And then this is the key biplane fluoroscopy is very, very important. You can do this in single plane rooms, but, but you're going to advance this lead and place this lead mostly in lateral, and so you're going to go lateral. You're gonna confirm placement in, in AP. So having biplane to begin with. Saves time because you're not constantly moving from lateral to AP to lateral to AP and and you want to make sure that you don't change these angles because the lead configuration on your fluoroscopic image is going to change if the if the lateral angle is 89 or 90 instead of 85 or 87. So if you change that angle, you're constantly going to be seeing different things. So in order to keep that standard, you want to do AP and lateral, you need to have biplane fluoroscopy. So again, here, this is key. So once the patient is under general anesthesia, you're going to make a bunch of markings. So this is mid sternum. This is the level of your carina here that you mark because you wanna advance the lead up to the level of the carina left sternal uh margin here, the left sternal margin is where the lead is going to be placed. We're not gonna put it directly underneath the sternum. You're gonna put that lead over here. It's sort of over the right ventricle. Uh, you wanna make sure that you know where your xiphoid process is and where your zipy sternal junction is, your left costal margin. And then your right costal margin and you will make these markings, uh, pre-implant on the patient, uh, because once you make them sterile and stuff like that, you can't really do those kinds of things, um, so you want to make sure that this is all set up for you before, um, you, you, you, you start to make an incision. Again, so when we look at, when we look at this, um, this is the sternum. Uh, this is the xiphoid process. You're going to be basically going underneath the xiphoid process and tunneling in this sort of substernal. Anterior mediastinal space, so the lead's gonna be here and, and so, so it's, it's very, very important to have a CT to recognize that you have enough space there. You don't have too much space, but you have enough space there to put a lead in there that can sort of stay in contact with the heart. So having a CT scan uh and looking at these sagittal sections becomes very, very important as sort of pre-implant planning. Again, this is, this is a a cadaveric uh uh um pictureization of of uh the sci-fi process uh the incision location so let's go back here so let's go back so the left, this is the left costal margin here and you're essentially gonna make an incision down here, so right below the left costal margin and you're gonna sort of aim towards aim the aim the tunneling tool towards the, the left sternal margin. And so let's go forward now a couple of slides. So basically when you make the incision here you're gonna see some diaphragmatic attachments here and you're gonna use your finger to actually puncture through those through those diaphragmatic attachments and you need to have a strong index finger. I, I've kind of struggled through this a little bit, uh, in, in the cases that I've done, but you need to be able to push through those diaphragmatic attachments in older patients, pretty easy to puncture them in younger patients who have who have. Good diaphragmatic attachments, healthy rectus sheath, healthy fascia, it's gonna be very challenging to push through those diaphragmatic attachments. Pushing through those diaphragmatic attachments is going to get you into that, into that retrosternal anterior mediastinal space. There is a space there you've already confirmed that, uh, on CT scans, so you want to get into that space. And so, so that's this is the sort of the space that you want to get into and so getting rid of those diaphragmatic attachments becomes very, very important. Once you do that you are going to feel the heartbeat on the fingernail you are gonna feel it and this is for for those of us EPs who have never been in this space intentionally this is, this is pretty cool. This is pretty cool uh so you kind of feel the heartbeat on your fingernail and once you know that once you feel that you know that you're in the correct space and then you have a tunneling tool that you can use to sort of get you into the into the right space so very shallow angle of tool entry. You push it forward, um, and I'll show you a picture of that, uh, you wanna stop if you feel resistance, obviously, uh, you're going to use biplane fluoroscopy, AP and lateral, and you want to advance the tunneling tool in lateral, and you want to confirm the positioning in AP fluoroscopy. So again, here, if you can look over here, this is the sternum here, this is the retrosternal area and the anterior mediastinal sort of area, and you wanna be in this space here, so in lateral, you want to sort of move up. Here and you wanna sort of ride the bottom of the sternum you wanna be able to feel the bottom of the sternum as you go here that gives you the best chance of avoiding everything you wanna avoid the heart you wanna avoid the limur you wanna avoid the lungs, so it is important for you to be as high as possible, shallow angle of entry, but you want to sort of ride the bottom of the sternum. So if you start to feel the sternum, you're in the correct place, you're in the correct place. You want to tunnel the lead uh to the carina and like I said over here, you want to avoid everything in here that can cause you to have a major complication. Now, once you go up to the carina, also remember that the right atrial appendage is a pretty superior structure. So once you go up there, you may have P waves, you may have good R waves, but you may have P waves as well. So, but, but going up top helps you, gives you the margin to pull the lead down so that you can still maintain R wave sensing and minimize P waves to, to a point where you can program around it, OK? So you can pull down the lead if you need to. So again, advanced in lateral and you take AP to confirm it and you want to sort of be on the left sternal margin and again the important thing about the pre-implant markings is part of the tunneling tool, part of the tunneling tool is inside is underneath the sternum, but half of the tunneling tools. On top of the of the of the of the chest, so having those implant markings there means that you're moving in, in a straight direction so you not only have lateral flora and AP flora to confirm, but you have markings on the chest that sort of help keep you in, in the correct direction. If you go to left, you are going to place this in the pleura and that's exactly where you don't want to be, uh, and again, like I said, please, we want to avoid the lungs, avoid puncturing the heart, and avoid the LIMA if possible, yeah. Um, so again here, so once you position the lead, you're going to test R waves and P waves, and, and as long as you have small P waves and, and larger R waves and you think that you can program around it, you're going to be OK. If not, you want to pull it down. You don't want to pull it down too much because remember here again if you look over here you have a defibrillation coil here sensing electrode number 1. Defibrillation coil number 2, sensing electrode 2. This sensing electrode 2 has to be above the zipy sternal junction. It has to be at least 1 centimeter above the Zipy sternal junction. If it's too low, you're not going to be able to use that as a good sensing electrode. So you want to make sure that as far as sensing is concerned, as far as defibrillation is concerned, you have as many vectors available to you as possible, OK. Once you know that R and P waves are good, you want to test impedances, and once you test impedances and you know things are OK, the first thing you want to do is suture leads. You want to suture leads down to the to the rectus uh uh sheath fascia, and you want to suture them down and you want to put down 3 sutures and suture it down and make sure that they're tight. Then, as we would do for a sub QICD, we're going to tunnel from your substernal incision here to your pocket. Once you tunnel the lead to the pocket, you'll connect it to the device. Um, you'll, you'll close the pocket, you'll put a Tyrex sleeve in there, and then you'll do DFTs, OK? And then you'll do DFTs. In the entire process, the procedure should take anywhere between, uh, an hour and a half to 2 hours is, is what our experience here at Centera has been. That's the experience that's been, um, uh, nationally as well, and globally. So this is a patient that we, uh, that we did, uh, it was my, uh, 3rd patient that we did. It was a 32-year-old male with hypertrophic cardiomyopathy, family history of sudden cardiac, uh, death who got a primary prevention ICD here, and you can see here under, uh, AP, uh, fluoroscopy here, uh, X-ray here you can see the lead sitting in a very nice position with the defibrillation coils facing towards the patient's right. The sensing electrodes facing towards the patient's left, so it's a it's a it's a, it's, it's the correct way of doing this and you can see here that the that the can is in a very nice position over here, um, and the leads are tied down and things like that. We got some very, very good R wave numbers here again, here's your carina, so we had to pull it down just a little bit from the carina to avoid P waves here. I'm going to show you a procedural animation that was uh. Uh, this should take about 2 minutes to do this procedural animation here. Again, so these are pre-implant markings, um. That we're gonna do first. Again, very important to sort of do this. You're going to make an incision to the left. And this is what it looks like, really. You're gonna put your finger in there. And you're gonna push hard, you're gonna push sort of downward and hard once you get to the right plane because you want to get rid of those diaphragmatic attachments and like I said, once you get rid of those, you should feel the heartbeat on your on your nail bed there. So it's just blunt dissection. And then this is the tunneling tool. So I, I told you that there were two parts of the tunneling tool. This is the, this is the part that goes underneath the sternum. This is the part that helps keep you, uh, towards those pre-implant markings on the outside of the body. So you're gonna have a shallow angle of entry and you're gonna push this through here, and again on AP fluoroscopy here you can see the heart shadow here you wanna miss that heart shadow and you wanna keep going straight, you're gonna leave a uh an introducer in there. And you're going to deliver the lead through the introducer again, once you put the lead through the introducer and you pull the introducer out, the lead is going to form the epsilon shape and the key here is the defibrillation coils have to be towards the right side of the patient and the sensing electrodes have to be on the left side of the patient. And you'll see how when the sheet is pulled out, the lead's in a perfect position here. uh, this tool up here is just marking the carina up there. And once you've secured the lead now using sutures. You want to create a device pocket here and again like I said, it hasn't, it doesn't have to be very posterior. You're gonna use another tunneling tool to get you into that space. The lead gets pulled in there, the generator gets attached there. And then you close it up Like a standard closure technique, and this is an example of a very nice lead kind of like our lead that we just showed you with the generator here and again it's it's, it's in this retrosternal sort of anterior mediastinal area here with the lead with with the generator in a very, very nice position here. OK, so when we look at device features, you have sensing vector options, you have pacing vector options, and, and again, the key here is to place your lead in a position where all of this becomes available to you. So as far as sensing is concerned, so R wave sensing becomes very important. You need larger R waves, very small P waves, so you can either do ring 1 to ring 2, ring 1 to can, or ring 2 to can, and then your pacing vectors are the same, except you're going to do ring 1 to ring 2. You're gonna ring 1 to coil 2 and then coil 2 to coil 1, so you have pacing and sensing vector options. It's very important to sort of have all of that available to you, um, at the time of, at the time of, uh, device uh closure. This is defibrillation, uh, this is defibrillation, so you can, standard is coils to can, but you can also do an alternate which is can to coils, and we're going to test that in, in DFTs at the end of the case. So your permanent pacing mode as far as uh as far as this is concerned is OVO. So patients that need active pacing, you would never put this device in them. This is basically like a shock box which also gives you ATP. So you're gonna program this in OVO, um, and if you need pacing after a device, uh, has been, uh, after a patient has been shocked, it'll be VVI 40 for about 30 seconds. And then again, following this pacing therapy, the, the, the defibrillator will return to an OVO mode until therapy is called again. So, again, three things that can, it can do for you. ATP, so both fast VT and, and VF zones. Uh, you have, uh, fast VT and VT zones. You can do post shock pacing, and again, if you need, um, uh, because of pauses, if you need pause prevention pacing, it can do that for you as well. So, so three important things that this is, that's available here, that's not available, the sub QICD. This is another patient that we implanted who actually got VT terminated by ATP. This was a 60 year old female who had sustained VT, secondary prevention ICD. Uh, patient had syncope with a sustained VT as she was traveling in Aruba, and, and the guys in Aruba, uh, did a very nice job and got me an EKG. It was fantastic. She had a dilated cardiomyopathy, and so I decided to implant this, um, so the VT that she had after the procedure was a VT here at a cycle length of about 290 milliseconds. She got one burst of ATP here, did not terminate. She got a second burst of ATP here and it terminated pretty easily. So again, this patient, if she had a subQICD. Uh, would have got a shock for this, but we were able to successfully treat this with ATP. This is my, uh, our first implant here at Centera. Um, So obviously limitations and considerations of this device, this device is not perfect. We're still learning about this device. There's been only about 800 patients all over the world that have implanted like this. Uh, obviously they have prior sternotomy, so if they have CABH, valve disease, prior sternotomy, you gotta exclude them. There's no way to do this with, with people with a prior sternotomy. There's gonna be a significant learning curve for substernal access. Like having anger in the room has been tremendous for me because I don't, I'm not in that space, so having him there and teaching me some of the stuff has been tremendous. Um, obviously if patients need atrial pacing, if they need CRP, you cannot give them this, um, the long term lead. Durability data is still being e is still evolving, uh, as people get more experience with this, uh, we're seeing better outcomes globally as people get more experience and obviously you need to be, you need to have biplane fluoroscopy in a lab you need to have some really careful imaging that you do in order to have successful implants here. This is the post approval registry. This was just published in December of 20 November of 2025 again, uh, done by Ian Crozier who essentially developed this with, with, with, with the company. And so we have 70686 patients now with an implant attempt at 112 centers globally. We have 168 implanters in 23 countries, so this was real world safety and efficacy of the extravascular ICD through 6 months, so post approval registry. Again, based on characteristics, if you look at mean age, mean age for the enlightened registry versus the pivotal, enlightened younger patients, again, over a third of patients were secondary prevention devices. Uh, the mean LVEF was about the same, and about 17% of patients had sort of primary or idiopathic electrical disease, um, but again, the majority of those were hypertrophic cardiomyopathy patients. Um, so again, high rates of success, so over 99% of patients had good tunneling and lead implant success without a problem, and 96% of patients completed the procedure with a device, which is quite high. The mean procedure time was about 81 minutes or so. Uh, the mean R wave amplitude at implant is about 3 millivolts, which, which is kind of crazy because when we do transvenous systems we see R waves are like 10 and 15 and 20 sometimes. Here the mean R waves are smaller only because this is an extravascular lead. It's not a, it's not a lead that is actually in the heart, right? And about 98% of patients met both P wave and R wave criteria and had successful implants. When you look at defibrillation testing, 99% of patients had defibrillation testing success when performed at implants, so high degree of defibrillation success at implant. The mean energy success success was about 30 joules or so. And, and over, over 85%, so about 89% of those tested at less than 30 joules were were successful. So, so low energy DFTs, um, and it gives you sort of a 10 joule shock margin because the device can give you 40 joules, so 30 joules it sort of gives you a 10 joule shock margin. Uh, the primary endpoint here, uh, at 6 months they had a 97.8% freedom from, uh, chronic system related major complications. Uh, it was very, very, uh, in line with the pivotal study and again inappropriate shocks. They had 5 inappropriate shocks, 2 lead dislodgements, and 1 implant site pain. So the numbers are already looking better at a, uh, post-approval registry, uh, with, with more patients because implanters are getting more familiar with, with the new technology. If you look at appropriate therapy here again, appropriate therapy, 67% of patients have gotten shocks, uh, probably because they have VF, but a significant portion of these, about a quarter of these patients get ATP only for success, and this is again one of the advantages of this, uh, of this device. Inappropriate shocks. You can see here that your rate of inappropriate shock from 10% in the pivotal study has now gone down to 5.5%. And again. Uh, P wave over sensing is still the major reason why people have inappropriate shocks. So that's why it's very, very important when you do the initial implant that you sort of minimize your P waves at implant. And if you cannot do that, perhaps you need to go back and reconsider and wonder if this is the correct device for this patient. If you have an R wave of, of, of, of, of 2, and if you have a P wave of like 0.8, probably not the right thing for this patient, if the patient has the ability to convert to a transvenous ICD, you should do that at that point, just to, just to minimize the risk of inappropriate shocks for that patient. Again, so conclusions from, from your, from your registry here, um, high implant success rate, 96% or higher, 98% freedom from system related complications at 6 months, uh, very low infection rates, 1.4%. Again, no rates of sepsis, no, no, uh, no problems with sepsis or mediastinitis. Most of these are either infections related to the incision in the substernal area or the or the pocket infection. And again, there's been a significant reduction in inappropriate shocks compared to your pivotal trial because of some of these new algorithms that have sort of been applied to reduce the risk of shocks related to P wave over sensing. Future directions, I mean this ICDs are going to, um, are going to uh um evolve, uh, in, in terms of technology, your integration with with leadless pacemakers, for example, um, uh, you're gonna have extended pacing capabilities with these devices we still need long term data. We still need refinement of implant tools. Having a surgeon, having a surgeon in the room sometimes may not be, um, um, may not be, um, possible in smaller centers, but, but I think that, but I think that this technology will continue to evolve, and this has been a significant, um, uh, leap in terms of technology for patients who need these ICDs but also have the ability to get ATP as a result of this. And finally I'd like to thank uh Unger who's been amazing uh in the in the in the cases with us uh without him and Justin Roberts with cardiac anesthesia, these guys have been sort of constant in the cases uh with me uh and sort of guiding me through our, our first few implants um and having them has been, has been tremendous. The EP lab staff. and Medtronic have been fantastic in terms of supporting us as well. I could not have done this, guys, without you. Um, this is, uh, uh, my daughter who, uh, who had me put this on her because she apparently, uh, reviewed my slides. Uh, this is her at Virginia Beach General. Uh, she did her first cardioversion last week with me. She, she, she claims she did it, but she watched it. Uh, but this is, but this is, uh, young Iron in training here, young doctor Iron in training. So, but thank you all, uh, thank you to the system for, for your support thank you to, uh, uh, sort of a collaborative, uh, group of, uh, uh, of, uh, uh, EP lab staff, uh, industry, uh, cardiac surgery with Unger, and then, and then ASPC for, for sort of helping us launch this program and making it, uh, a. Success and we hope to do many more. I think uh I've done 3 so far. I've got probably 5 or 6 coming up in the next few months. Uh, we have Tania Hernilia who is also trained who is gonna start doing this as well so we really hope that we can continue, uh, uh, to do this in sort of a safe, uh, manner for our patients. Thank you.
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