Dr. Patel reviews the trials and research from the Heart Rhythm Society Conference of showcase groundbreaking science and life-saving therapies in electrophysiology.
One of our previous presenters had canceled, so they asked me to give a grand rounds topic, which I'm always happy to do. And so I thought it would be nice because Heart Rhythm Society had its annual meeting in San Diego last week. And so I just want to touch upon, I think, new developments in the field of electrophysiology and new things which are exciting, um, for the field of EP. So this is one of the late breakers that came out. It's by Vivek Reddy and Peter Nozel. They looked at the first inhuman study of leadless pacemaker system for left bundle branch area pacing. So there's two camps of electrophysiologists. Some are in the lead list camp because they believe in the. Lower pocket infections, lower systemic infections, they believe in less lead related complications and they prefer leadless pacemakers. If you talk to Doctor Woollett, um, he's a big proponent of leadless pacemakers. The other camp of sort of pacing is more the conduction system pacing. So can you get physiologic pacing. With the left bundle branch area pacing, with commonly used the Boston Scientific Inngevity plus lead or the Medtronic 3830 lead. And so what Abbott did was on the top you could see this is the ventricular device on the top left. On the bottom is the atrial device, and we've been implanting of yours for at least 6 months here. Um, in patients. So what they did is they said, why don't we design an extended helix screw that extends out the traditional septum. So you can see it's the same kind of back mechanism as a docking button where you can extract from, same type of leadless mechanism, and here's the screw, but then like the 3830, there's an extended helix that extends out further, allowing for deep penetration into the septum. So they enrolled 14 patients um in Prague. Um, 12 underwent implant attempt, 10 successfully implanted. Uh, but you can see from this, it's preliminary because only 5 had selective left bundle area branch capture while the other two had RV septal capture and 3 had deep septal capture. So while it's a nice tool, a new mechanism, I think we'll see all of the companies developing this as the field moves forward, uh, to prevent pocket infections and systemic infections. You can see here it's an internal jugular approach, so this is RAO and LAO. It comes from the top. Usually the easiest access point is the right IJ, and it's a non-deflectable sheath, and then it allows for penetration on the LAO. Anything to the right is septal, and you could see this thing is extending into the septum and the screw extends out. This is a case, if you look here, the final location, they couldn't get a nice R in V1, so probably a deep septal location and as you can see on ice, this white thing is the leadless pacemaker and it's penetrating deep into the LV septum. This is another patient, patient number 8, similar approach from the internal jugular with a non-deflectable sheath. The helix extends out further, and in this one you get a nice R indicating that you get more of that physiologic left bundle branch capture. Um, so I think it's a nice tool. I think we'll see all of these companies develop, um. These kinds of leadless pacemakers that take advantage of conduction system pacing to prevent pacing induced cardiomyopathy, because as every electrophysiologist knows, the worst procedure is an upgrade to CRT. So this is a case that I did about 6 to 8 months ago, um, and it dovetails nicely into a study which was just presented as a late breaker at HRS. So it's a 20-year-old male who presents to ER after witness syncope. He states that prior to the episode, he started feeling lightheaded and dizzy, and then everything went black. Um, he's had this happen multiple times. This is his second ER visit. And you can see here this was caught on his Holter monitor. He becomes asystole and he has sinus slowing. So true vasovagal syncope, uh, where his sinus slows, he has AV block and obviously anyone with an eight second pause is gonna, is gonna pass out or become lightheaded. So we tried compression stockings, fluids that ultimately didn't work. Um, so. Why did these things happen? It turns out there's these ganglia plexi or parasympathetic nervous system fibers um located on the outside of the heart at key areas. So one is the SVC junction, the others are outside the pulmonary veins, and one's outside the coronary sinus. And so these cause a lot of patients to have vasovagal syncope. Um, from a cardio inhibitory standpoint. So they get sinus slowing, or they get AV block or a combination of the two. So I took this patient to the lab, um, for an ablation around these plexi. And you can see this is his Holter monitor before and after. So he wore his Holter monitor before the lowest heart rate was 43, the average heart rate was 75. After his ablation, the average heart rate went up to 98, so true 23 beat increase in his average heart rate, um, and as you can see here, no syncopal episodes, um, after the ablation. So Rod Tun presented this nice multicenter study, um, looking at multiple centers in the US looking at cardio neural ablation for functional bradycardia and vasovagal syncope, and they looked at outcomes. So these they enrolled about 250 patients with recurrent VBS or symptomatic functional bradycardia refractory medical therapy, and behavioral modification. The approaches are, you could say, I want to implant a CLS pacemaker. Um, traditionally, Biotronic has an algorithm where it looks that you're gonna pass out. It looks at um RV. Volumes and it decides to pace in response to that. You could do leadless pacemakers because the patients are young, or you could do cardio neural ablation. And so what they did in these patients is all of the patients got cardio neural ablation, and you could see pre CNA, the number of syncopal episodes per patient was significant and you could see that the majority had a marked reduction. There's no bar grafts to the right here in vasovagal syncope. You can see that the heart rate at baseline, gray is uh at nighttime and then blue is daytime. You could see after ablation, the heart rate significantly jumps up, uh, preventing that sinus slowing or cardio inhibitory nature. Um, the heart rate variability drops, so it's not going from a heart rate of 43 to 10,860 or 70. Um, you could see that their baseline heart rate goes up and the procedural complications were all due to transeptal access. Um, so any kind of afib ablation or SVT ablation on the left side, 4.7 was a little high, uh, but all of them were due to transeptal access and none were due to just cardio neural ablation. So this was a nice editorial for the paper, uh, describing the registry by Doctor Shiv Kumar at UCLA, one of the pioneers in anatomy and ablation, uh, where they call it a new hope for these patients. So they say to conclude, the author should be congratulated for their detailed study, highlighting risks as well as important benefits of the therapeutic option for patients. Many of these patients had debilitating symptoms that was relieved by interventional approach. Therefore, this is real hope, and it is time to get the message across the community to increase awareness among clinicians that more studies can be done to generate the evidence which can firmly establish as therapy and routine clinical care. So I think if you guys or anyone has patients with vasovagal syncope or cardio inhibitory, I think one of the approaches we should consider as cardio neural ablation. In addition to CLS pacing or um leadless pacemaker. How morbid is Yeah, it's a, it's a 15 minute afib ablation. So it's, it's like an afib ablation, but the length is probably half the time length. So all I do basically is put a catheter on the right side, look for fractionated signals, go on the left side, look for fractionated, and I blade, and I look for a vagal response. Increasing heart rate and usually on the left superior pulmonary vein, you'll see AV block. There, as you know, there remains kind of naysayers about this that are pretty adamant, particularly, you know, the concern in looking at that heart rate variability, I think that's more looking at power sympathetic. Um, effects on, on heart rate and and and that's felt to be a good thing actually to have when you look at stress responses and and illness, you know, system illness, decreases in heart rate variability actually for worse outcomes long term, um, you know, those sorts of things and in fact it's been thought this is going back to military days to use heart rate variability as a way to track, uh, you know, your, your soldiers and whatnot in terms of another vital sign, um. So you know one of the concerns is that our data is all short term. We don't have a longer term in terms of what's gonna or how this is gonna affect it and otherwise essentially healthy system and and particularly in concerns longer terms for malignant arrhythmias and those sorts of things and so. That's one of the things that we hope to get. I'm not aware of any longer term data 10, you know, 10 years or on that. So I mean I think if the, the key is is debilitating symptoms if someone has had one syncable event, um. You know this may not be the one for them, but in some where you tried other things this is a reasonable consideration with counseling in terms of some of these things that are still remain unknown. That's a good point. There's some animal studies showing that if you get coronary vaso spasm later, you may be more likely to have VFRS. Um, so there is more, um, data needed, but I think the hope is you do more of these multi-center registries and find out if it's working or not. So, as everyone knows, I'm a big fan of ablation. Um, and so one of the best papers that I read this year was published in New England Journal by, uh, Doctor Sapp and Stevenson, among others, looking at catheter ablation or antiarrhythmic drugs for ventricular tachycardia. So we know in patients with ischemic cardiomyopathy who get defibrillators, so patients with coronary artery disease or previous MIs, they are at high risk of having ventricular arrhythmias, especially because the scar creates re-entry. So in the previous Vanish trial, they looked at if patients, all patients were on baseline antiarrhythmic drugs, they looked at, should we escalate antiarrhythmic drugs at a second agent, so if you're on amiodarone admixiline, or increase the dose of amiodarone versus ablation, ablation did better in those patients. So head to head, if you escalated doses, ablation beat. Um, escalation of antiarrhythmics. So they designed this trial looking at same thing, ischemic cardiomyopathy patients, um, with existing majority of them had existing ICDs. They said, should we do an ablation or should we put them on antiarrhythmics to prevent ventricular tachycardia. So the antiarrhythmic choices were sotalol or if they had a low EF and there was a contraindication amiodarone. And what they versus ablation, they randomized them to catheter ablation and drug therapy. Majority were eligible for amiodarone, some because they were young, were not eligible for that. They were eligible for Sotool, 46%. Um, there was equal VT episodes in both groups. At least 50% had at least one appropriate ICD shock. Uh, 23% had VTSTORM, um, multiple, um, about a third to 1/5 had episodes of treating with ATP, uh, 5 or 6 times. So a lot of these patients were having arrhythmias when they were enrolled in the study. And you can see here the Kaplan Meyer, um, survival free of primary endpoint. So they grouped all of these endpoints together. So they grouped death from any cause, appropriate ICD shocks after a blanking period, so it probably takes 2 weeks for amiodarone to get loaded, a VT storm after 14 days and treated sustained VT below the detection limit of the ICD after 14 days. And yet, as you can see from the Kaplanmeyer on the left catheter ablation, um, significantly. Um, showed a significant benefit compared to drug therapy of amiodarone or sotalol in patients with ischemic cardiomyopathy. So I think, um, as a group, we practice towards if you have an appropriate ICD shock or you come in with ventricular tachycardia from scar from ischemic cardiomyopathy, um, you should be looking at getting a catheter ablation at some point, um, because drugs seem to do worse. And sometimes it's hard getting those patients in right away, but sometimes what I'll do is I'll put them on amiodarone, um, so they can go home and be treated as an outpatient until we can get them in for the VT ablation, and then as the VT ablation works, take them off the medicines. This is a nice study, um, and this is a case I did last week, and I was fortunate to have Doctor Robertson come in, um, and Doctor Gently, um, walk into a room, but it's a CT and MRI guided VT ablation. So, um, this is the kind of cool complexity stuff we do at Centerra and we're lucky to have lab staff and cross collaboration uh between disciplines here that helps out. So as you can see here, this patient has an ICD. Um, there has a CRTD with the left bundle lead. This is the atrial lead, this is the ICD lead, multiple ICD shocks, and his etiology was non-ischemic cardiomyopathy. We know in patients with non-ischemic cardiomyopathy, most of the scar is on the epicardium of the heart, so on the outside of the heart. So as you can see here, I put up an ice catheter, I did a transeptal axis with an octaray. In the left ventricle, and then I got epicardial access and put my ablation catheter and it turned out all of the scar was on the outside of the heart. So you could see here this is an epicardial VT that I induced. You could see by the sluring true delta wave that most when you see sluring like this, it's not located in the endocardium, it's located on the outside of the heart. So got epicardial access, mapped it and saw lots of areas of scar that needed ablation. Uh, and fortunately, I was, I told Doctor Robertson and he was happy enough and kind enough to come in and do a left heart catheterization during the procedure to make sure my ablation catheter is far away. From the early data, we know that our RF ablation can. Cause thrombus if you ablate near coronary and it can cause significant issues that can cause an MI it can cause shock, and then sometimes interventional has to come in and stent the thing. So it's nice to make sure you're far away from any coronary artery before you la on the outside of the heart. So Doctor Robertson did a left heart cath, I'm just looking at the LAD and left main and you could see my ablation catheter on the right as far away from any branch affected. So I've lad that non-inducible at the end, the patient's doing well a week and a half later, um, without further recurrence of VT. But the question is, can we obviate the need for a left heart cath? We have good imaging these days. Can we get better imaging before preparing procedurally so we don't need to do a left heart cath intraoperatively. And so you can see there's this company called In Heart Medical, and they basically what they do is they get a CT scan. We get a CT scan normally, just like we normally do, and they can merge the map, um, that you're gonna get while mapping in VT and they can map merge the coronary arteries and delineate scar, um, during these cases. So you don't need a left heart catheterization during the case, you're able to go to the target area of interest pretty quickly using this technology. They didn't have a published paper, um, but you could see that they randomized people to this imaging software versus not, um, and they found that the imaging software reduced procedural time by 28% because you know where the scar is and where the border zones are, procedural costs by 11% and improved the one year free VT free rate to 77% compared to 67% without image integration. So I think one of the things, just like the structural guys use dossi simulation, we will be getting this at Centera and we're thankful to Service Line and the Heart Hospital for obtaining this technology to speed up the process of VT ablations and not need to utilize the cath lab members as much, um, for left heart catheterizations. This is the Omni catheter. Um, so right now at Centera, we've been using mostly Medtronics Afera ablation catheter, and we've been using, uh, the Boston Scientific Ferro pulse catheter. This is made by Cardo or B Bense Webster, J and J Company. Um, it's like the Afera, except it's a bigger catheter. Um, it maps and ablates the same, and they enrolled 136 patients in Europe. We will, we will be starting the Omni pulse trial. Doctor Keel and Hedley are the operators, I think in the next month or two in the US. And so it's similar PFA catheter, similar pulmonary vein isolation. They looked at both how good is the pulmonary vein isolation, what is the amount of time you need to isolate the veins. And um what is the safety endpoints. It turned out 3% safety rate, which is in line with previous studies, 3 vascularis complications because in Europe, they don't use ultrasound as much as we do. One pericarditis, zero esophageal injuries, 0 PV stenosis, which is great to hear, just like in line with the other ones. 5 minutes of fluoroscopy and the amount of time you need to do PFA is very limited. It's 176 seconds. Um, it's a short procedure just like the other PFA ablations, about 30 to 45 minutes. Uh, the PVI durability was 85%. That means in all patients who got this kind of isolation where you're doing a ring around the veins like old cardo, um, it turns out 85% of the veins were durable, 15% when they went back in were reconnected, um, which is slightly higher when. From the data we're seeing with the EEA and Ferrial studies, uh, but the US study, there will be more data and more to come from this kind of technology. I think this was a nice study uh by Peter Kessler's group, um, looking at the impact of mitral regurgitation outcomes of catheter ablation of Afib. So in patients, let's say you get a patient in your clinic, they have severe mitral regurg it looks functional because the left atriums dilated, left ventricles dilated. Uh, they looked at patients whose EFs were less than 50%, persistent afibs, so always in afib. And they said, does it matter how much MR you have, whether you'll get a benefit from catheter ablation? And it turns out it doesn't. So even if you have severe functional mitral regurge low EF and you're thinking you wanna refer them for mitral clip or advanced heart failure therapies, I think it's important to consider ablation of their Afib and getting them into a normal sinus rhythm and then reassessing their MR. Uh, because a lot of these patients will have a significant reduction in functional mitral regurgitation. They saw this in 90%, a significant fun patient proportion will have a decrease in functional TR 85%. You could see the market LVEF improvement about 25%, and so you've remodeled the LV, you've remodeled the LA, you've remodeled the mitral regurgitation. Showing a true benefit of catheter ablation in persistent AF patients with an EF of lower than 50%. Um, so I think the structural guys always ask to see what. The mitral regurge looks like after an afib ablation or CRT, uh, because a lot of times those patients will see significant improvement. Um, so I think it's important to consider both ablation and CRT to improve MR before referring for mitral clip. This was a nice study um by this group, I think it they were in Singapore or something or Japan, uh, where they looked at Brugata syndrome ablation for prevention of VF episodes, the Brave study. So we know in patients with Brugata with sudden cardiac arrest, they should get an ICD, but a lot of those patients will have recurrence of VT or VF. Um, the usual practice is to put them on uinidine or an antiarrhythmic. Uh, but more and more groups have been looking at epicardial ablation for Brugata. We know Brugata has scar on the outside of the heart, and if you target that scar, not only can you get rid of the Brugata sign, but you may prevent VF. So they randomized 50 patients, 25 control patients, 25 ablation patients, and as you can see on the right. The VF probability after epicardial VF ablation for Brugata, the ablation patients did much better than control, um, which involved antiarrhythmics, and a lot of the control had to cross over. So I think if you have a Brugata patient who has an ICD shock, I think it's important to consider epiccardial VF ablation. I think one of the hottest topics uh during HRS was when are EPs going to leave the hospital for ambulatory surgical centers. Uh, multiple studies were published at HRS, Multiple private equity groups, um, electrophysiologists in the hospital systems are discussing this. Um, this was a study out of Europe, uh, published. This is the 4th study to come out this year looking at the safety and efficacy of catheter ablation of afib in an ambulatory surgical center. And they looked at both their experience with cryo balloon, PFA and RF, and you could see with PFA, the nice benefit is the standard deviation in times goes down. So what do I mean by that? If you could see here, the standard deviation goes from 25 minutes skin to skin time to 150 minutes, PFA is much more predictable. We know that the timing of PFA ablations are. Probably skin to skin time of 40 to 60 minutes, um, and so that is nice because when you're trying to schedule cases in an ambulatory surgical center just like you're scheduling restaurant tables, you need to know how long people will eat, get out of your restaurant. You want to know in an ambulatory surgical center when is my surgical center gonna shut down. is it 5 p.m., 6 p.m. so you can schedule your cases and not have late state teams and things like that. So you can see here the safety was good. They had 0 cases of tamponade, vascular complications. Two patients required transfer. Um, to, to the hospital, but multiple studies have been showing the safety of doing ablation in an ambulatory surgical center outside the hospital. CMS is gonna rule on this in July, but I expect, uh, in the next year or two for this to pass and for Afib ablation certainly to move out of the hospital into an ambulatory surgical. educate me. Why is it cheaper? I can have more centers, um, I mean, we have plenty of hospitals. Uh, why do we need to build, uh, independent ablation centers when we have an ablation center? Yeah, so, so finances is that, uh, there's a guy in Alaska I talked to. How many cases do you think he runs in one lab? How many cases, how many EP cases can you do in one lab? By 4 p.m. he does 8. But what's the difference? So 15 minute turnover times. Yeah, I mean, so it, yeah, so I, yeah, so the hospital is, I think a lot of times the hospital has too many, too many layers and the complexity is higher. So what do I mean by that? Outpatients are lower complexity than inpatients. Uh, the anatomical issues of inpatients is higher. And so it gets into patients are you can have a lab in the hospital this is gonna be our 8K lab, and you can't put complex guys on vents and you know. Yeah vascular disease, it's, it's what's unique about a building that's outside the hospital. Now I understand CMS has some crazy rules where you know, if it's not part of the hospital, you can build this, but if that's what it is, that's what it is, but I mean if you take that away and go to the bare bones and what are we doing differently and then freestanding center. It's just more, much more efficient. The patients are, there's one room, one lab, they go to one waiting room, there's no PACU holds. There's different layers of stuff. Uh, that if you walk through the process of getting an ablation in the hospital, it's a much more tedious process than an ASC. Again, why can't we model that? And I understand because there's so many layers, but if there's a, if there's a holy grail if we did this, we have that, what is the difference between whether you have the, the ablation room inside a hospital or standing out in the parking lot? I think the short answer is one could do that if one had an incentive to do it. That's exactly right. There is, there is currently no incentive for the hospital to do it. Um, there is incentive for systems to look at it. Uh, CMS has a huge incentive because their plan is to cut reimbursement by a significant amount. So what they're looking at is decreasing, you know, uh, uh, costs, and, and so they, they, they look at this as a way to just. They, they've moved a lot of care outside of hospital. Hospitals are expensive places to deliver care. We all understand that there's many different reasons for it, but you know, in many hospitals include our own, there, there isn't a sufficient incentive. To achieve this goal, but maybe in time there would be, but you're exactly right. You could say these two rooms are ambulatory surgical center and this is where we're gonna, we're gonna streamline and and do that one could look at doing that, um, and, and honestly I, I mean, I think for the system it would, it would make a lot of sense. The only issue would be is, is if there are some different financial types of incentives is how do you. How do you replicate that to achieve that kind of efficiency, um, there's a lot of significant inertial challenges to doing that in a hospital. Yeah. That you're able to overcome when you get, uh, you know, and, and there's shared incentives that that have allowed for this to occur, obviously you have to have people that are motivated in many different ways and and a lot of it quite frankly is tied to financial incentives that the whole it's like the employee owned business, right? Everybody has a share in the stake of success. What I'm saying here is it's there's nothing new here other than organizing the same pieces on the board, you know, but we have this extended recovery. I agree, yeah, but, but, but we, so what I, what I'll say is we get more of a say. Yeah, so if, if you have ownership, you have more of a say in when the case last case is done, you could say uh last case will be done at 3 p.m. You could say this is the efficiency we expect and this is. Anesthesia has buy-in. Um, there's different parties that have buy in. And not to make an argument out of the hospital, if this is a financial incentive, you would think that this hospital would sit down and say, OK, we want to model this in our own hospital to to make the financial incentive work, improve our profits and and uh our employee satisfaction. I think though what Alan's point is you take one of these labs that have bought another whole set of equipment, take one of them and say this is a. You know, this is the ASC sitting right here because this labs ASC, the rest of them are. Yeah, you could do you know the equipment. Yeah, but what I'll say is it's nice having a yellow line across the floor. One is ASC and the other one is. Yeah, it would also increase capacity at a lower cost than trying to build another lab, yeah, exactly, and what's the waiting time for an ablation now it's sometimes months. I, I think the ASC has incentives for physicians, anesthesia, and, uh, lab personnel. I think less of an incentive for the hospital system. All right. Uh, this is the last study that I'll talk about. So this is, um, pacing considerations in patients undergoing trans catheter tricuspid valve replacement. Uh, one of the challenges has been in the structural heart community, there are some companies saying that you should just implant a tricuspid valve and not worry about pacing leads. Uh, the reason for that is multifactorial, but uh sometimes it has to do with if you extract the lead, I think the TR gets better and then the company's valve doesn't get implanted. Uh, but a lot of places have been jailing pacemaking leads. So the Emory Group looked at 73 patients who underwent tricuspid trans catheter valve replacement. And they jailed about 14 patients. So what does a jailed lead mean? That means you have a pacing lead. This is one of these is abandon, one of these is functional, and you just say, screw it, I'm just gonna put the new valve right there. And guess what happens? About 20% of those fracture. So one patient died because they had complete heart block and their leads stopped working. And so I think as a community, um, this what this paper showed and what the evidence is showing is that we should have a multidisciplinary discussion about should we jail the lead or should we extract and put in a lead list before they get their trans catheter valve replacement. There's nothing worse than you replace the valve, um, and then your lead is nonfunctional, um, in the future in 6 to 8 months. And so I think we do a good job here with the structural heart team. Do a joint discussion about all cases where TR affects pacing leads or the TR is caused by the pacing leads about the approach we should take, and I think we'll see as these valve companies realize that these leads are failing and their patients are having worse outcomes, I think we'll see more data on extraction before valve replacement in these patients. I think that's it.