Hi, I'm Eric Pistowski. Welcome to another segment of EP on EP. It's a delight today to have Dr. Vivek Reddy with us. Dr. Reddy is the Director of Cardiac Electrophysiology at Mount Sinai and Vivek, I know very few people who've done so much on the front lines of developing technology and there's so many areas I could ask you about, but I would love to get your views on leadless pacemakers. You've done some of the really seminal work there. So let's start with, we know one's available, so let's just start with the indications. I must be frank with you, we wrestle with that at times because it is more expensive. And tell us your perspective, what are the patients that sort of should definitely get it and maybe the ones that would be useful? So first of all, Eric, thanks for having me. Let's start off with what the studies looked at. The studies of leadless pacemakers, as you know, were all single-chamber studies, specifically single-chamber ventricular pacing. So these are VVIR pacers. So when you look at who potentially qualifies, we're already talking about the VVIR patients, which at least in the United States is about maybe 15% of the total pacemaker population. Now you brought up the very important point of cost. These devices are clearly more expensive than standard devices. So when you think about which of the VVIR patients would be eligible, I think there are a couple of different types of potential people. One is actually the really young patients. So if you have a young patient, for example, who requires VVIR pacing, you don't see that often, but occasionally you do. So say somebody who has transient AV block or something like that, where you don't need continuous pacing, but you just need the backup. That's the kind of patient where we will consider putting this because this is something that this patient is going to have for a very long time. Because remember, the advantage of the leadless pacemaker is you're well aware is to avoid the lead and the potential complications of the lead. So that's the real question. And then there are other obvious patients, for example, patients who have infection. So you have to take out the old device, and those are patients where I think, again, this has real advantage. There are patients who are high risk for infection. We actually do consider this in patients who need VVIR pacing, for example, have, let's say, dialysis patients. That's another population. And then occasionally we have patients that are just really sick, and you just sort of want to do something quick. So I think we would consider in all these patients, and really, I think it's a good device for most patients, but I agree with you, you sort of have to triage. So those, especially the latter ones, all make a lot of sense. We're newer to the game than you because you were one of the early ones into this. Let's take a bit about the younger patient. You can't, once it's in, it's in, right? So let's say you're talking about a 35 to 40-year-old who you would rather not use a lead. Are you okay with the fact that you might have to put four or five of these in? What is your thought on that? Yeah, it's a good point. So one of the advantages of these leadless pacemakers is that their battery life is really long. It's not uncommon to expect a battery life based on their use characteristics. It's not uncommon to expect 12, 15, even 18 years of battery life. I didn't know it was that long. And part of it's related to less lead, no lead, basically, the advantages to that. So I think that's one point. So the number of times they're going to need a change or an additional device is not as much as you would think. Number two, it is possible, actually, at least with some of the devices, to take them out to retrieve them out to maybe six, seven years. So far we have data on that. Actually, not seven, six years. Oh, I didn't know you could take three. I'm not saying it can universally happen, but probably 80 to 90%. That's what it seems like. But there's still patients where you can't take it out because you have enough tissue overgrowth that's completely endothelialized and fibrous. In that situation, basically, you can just put another device next to it or in a slightly different location. The reality is these devices take up about one cc, actually less than one cc, volume. So the amount you're actually displacing is really quite small in a right ventricle. Okay. But is there, when you've put these in, you know, there's all this issue about where to pace. I mean, we have now his bundle pacing and all this high septum. Is that a non-issue here because there are only certain places you can actually place them? Yeah. So this is, I think this is one of the most important issues. I mean, you bring up the very important point that his pacing has really seen a resurgence in our field, right? For the, I think, appropriately obvious reasons. Now, in my mind, that is the biggest limitation of leadless pacers at this point because you cannot do his pacing. Maybe in the future we will, but right now you certainly can't. Okay. Mitigating against that, if you look at all the patients, for example, in the trials who received the VVI pacemaker, it's less than 10% of the patients, more like about, I think it's like four to 5% of the patients that actually ended up requiring upgrade to CRT. So while it's a very important issue, at least to the point where it requires CRT, it's still a really small number of patients. Okay. Okay. But I think, look, I think the his pacing issue is an important one. Okay. And if you have somebody, for example, who has, let's say, marginal LV function, let's say you're going to do an AV node ablation and pacemaker, I would, that's not a patient I'm excited about putting a leadless pacemaker because you'd probably worse the ventricular function. Either CRT or his. I'd rather do a CRT or his. Exactly. Exactly. So that's a great summary of, of, of sort of the indications. Let's talk about the actual procedure, Vivek. Sure. You've done so many of them. Anything you can tell us as far as things to watch out for or complications? Yeah. So, you know, when we first started doing these, we were most worried about the groin because you know, it's a large French sheath. And it turns out actually using a figure of eight stitch at the end to sort of scrunch up the tissue works really well. And the groin complication rate has been extraordinarily low, much lower than we, at least I initially, initially anticipated. But the one very important critical complication is pericardial effusion. Now obviously we're, we worry about that anytime we put a lead in the heart, right? But if you have a pericardial effusion with a leadless pacemaker, it tends to be a big one. So it probably has to do with the size of the device being, you know, obviously bigger. So I think one has to be very careful. Now, what does that mean? Well, obviously if the patient's had previous cardiac surgery, you know, you're home free, but the majority don't. And in that situation, really you want to try to put the device into the septum, in the ventricular septum. So try to avoid the free wall. You know, most of the devices now, the delivery catheters are sort of designed to sort of cant toward the septum. So they're designed to help position them. And so one just has to be careful during the procedure, you know, check RAO, LAO, you could inject contrast to the delivery catheter so you can see where you are. So identifying whether you're on, whether or not you're on the septum is actually not difficult to do. So it sounds like it's not as bad as extractions where you want maybe either a cardiac surgeon in there or very nearby, but you should be, it sounds like the smart move is to have a pericardial synthesis tray ready to go. I think, yeah, I think, I mean, honestly, I think, I think in most labs you should be ready to go. Right. Theoretically you should. Yeah. I think that, you know, especially I think when one is early in their experience and you're still learning how to do it, I think it's really not a bad idea to make sure you do it during the day when the cardiac surgeon is around. If someone's around. Yeah. Let them know about it. That's really useful information. And then once, after you have experience, then, you know, obviously you do it. That's fantastic. I didn't, I wasn't aware that it was that big a problem. So last thing, a brief moment to look into the future because you probably know what's going on. Not to look into every single thing, but what are some of the cool new things that may be happening in this area? Right. So as we talked about it, these are currently VVIR pacemakers. Interestingly, that one of the devices has a VDD capability, at least it's being tested in clinical trials. And the idea is the device has an accelerometer. So it's actually able to sense the atrial contraction. That causes a little bit of a shift. It senses the atrial contraction. So in those patients that need the VDD capability, not necessarily atrial pacing, you know, the heart block patients. Right. This is a very interesting option. That's actually pretty cool. Right. And then one of the other companies is working on dual chamber devices that can communicate already in preclinical testing, it seems to work. So hopefully we'll be seeing that in clinical trials. And then the other company has a device that can communicate with the currently implanted subcutaneous ICD. In fact, it can actually communicate retroactively. So a device that was put yesterday, when that device becomes available, which will be available in clinical trials later this year in the United States. It will be able to do anti-tachycardia pacing, as well as backup VDI pacing. So are these years away, or some of these features like within the next couple of years maybe? Yeah, well, I mean, they're not that far from the setting of availability in a clinical trial setting. Gotcha. In terms of approval, you know, it takes years. Vivek, it's always a pleasure. Thanks for having me. It's great to have you here. Thanks, Vivek.

leadless pacemakers

patient selection

long battery life

complications

future advancements