Dr. John D. Rogers provides an update on what’s new in the world of Cardiac Resynchronization Therapy (CRT) devices including benefits for patients and providers.
Back to Symposium Page » I'm going to talk about what's new in the world of cardiac synchronization therapy. CRT therapy. And this is, um ah, therapy that's been available for, um um, gosh, going on 20 years now for for since inception. Basically, Um, and, you know, if you think about two thirds of patients, um, who have systolic heart failure, probably at least a third of those patients probably have enough to synchrony that they would benefit from CRT therapy. So it's, ah, therapy that's been around for a long time and has helped Ah, lot of patients. Um, here are Excuse me. I went too fast. My disclosures were there, but, um, if you look at what the cardiac re synchronization therapy is, it's a device based therapy where the patient has, uh, likely most of the time three leads going to their heart. One is to the right atrium, a lead to the right ventricle, whether it's a nice delete or it's a pacemaker lead. And then the third lead is a lead that goes out into the coronary Sinus, which he's into the right atrium out into the cardiac Venus system and out to where we want to find a lateral wall, a lateral epic cardio vein to place the lead. Unlike the arteries, where we can't place hardware or leads in an artery without causing a semi, the veins are much different. The veins are very interconnected on. If we put a lead in a vain that ends up closing off that vein, other veins take over immediately to return that blood supply. So the Venus system is obviously much more, um, forgiving. We think about the timeline of this therapy. The first reported case report out of Europe of CRT therapy Being effective was in 1994. Um, the first. I think my first implant of CRT therapy was around 2009 or 10, Um, somewhere in that timeframe. The first studies to show the proven benefit of CRT therapy were in 2011, 2012. So we're talking about a therapy that's been around for 10 Thio 14 years or so, which is, you know, it's although it doesn't sound like a lot of time. There's a lot of development and enhancements and improvements that have gone on in in this therapy, and so we're going to talk about what's new here. Recently a zoo. We talk about this today. See, I am not able to advance the slides, Scott. Okay, so thank you. So what is new? Well, we'll talk about indications. Turns out there's not much new there, but identifying the pain and the patients that would benefit from this therapy is really the emphasis there. We're talking about. What's new with the CRT devices themselves will talk about what's new with CRT leads. Really, What's new with the left ventricle pacing leader? The lead that goes out into the coronary Sinus is really what's really new right now. Um, in some cases, we'll talk about experience we've had here at scripts doing CRT optimization. All the enhancements that I'm gonna talk about within the devices are really about trying to enhance our CRT responder rates. What does that mean? Trying to help patients get better when they get this therapy. So traditionally and historically, it's About 30% of patients will not benefit or just won't see an improvement, and either an ejection fraction or symptomatically. What do I mean by symptomatically may be decreasing one or two heart failure classes, but a lot of what has developed in the devices are algorithms and programming, too, to actually enhance that optimization and that respond to rate. And it turns out there's a lot more than just within the device itself that we could do to help our patients respond. So we'll talk about that a little bit, too. And then just a couple brief mentions about what's coming in the future, right? So, like I said on the indications, there's not much new we're really looking at trying to enhance finding the population of patients that would benefit. So really, that's not something new. But looking at the at the indications, really, the classic indications are people that have a low ejection fraction, right? So people's ejection fraction That's less than 35%. They're QRS complexes wide. Remember normals less than 0.12 seconds. 120 milliseconds, Um, over 200 is considered a first degree a V block. But it's all about the patients who have a weak heart. And it's always been about the patients who have a weak heart ejection fraction less than 35% and a wide to RS. That's that's sort of the marker of dissing cranny for these patients worst case scenario left bundle branch block over 150 milliseconds, but a cure restoration greater than 120 milliseconds. And if you look at the original indications and these these I'll call the classic indications for CRT, it's people who are pretty sick with heart failure, despite revascularization and despite medical therapies. So New York Heart Association, three or ambulatory class for patients? Or if we think these patients are gonna be pacing a lot, that with low ejection fraction and they're sick with heart failure are the people that have been, historically, classically, the people who have been indicated for CRT therapy. But there's also indications for those patients who aren't that sick that are actually New York Heart Association class one or two patients so either relatively asymptomatic or minimally symptomatic patients, but who also have a low ejection fraction and who we expect we're going to be pacing a fair amount of the time in the right ventricle. In fact, if we look at made it to C. R T, which was a study that led to the AN, indicate this indication for the less sick patients New York Heart Association class one or two and compare that study compared I C D vs C R T d uh treatment and looked at left bundle branch block patients. There was actually a 34% relative reduction of all cause mortality and a 42% reduction in heart heart failure events. So for the first time, we have this indication that said, implant these in less sick people who have the potential to get worse and we can reduce their mortality and their hospitalization for heart and visits for heart failure. So let's prevent these less sick people from getting sick. And the newest indication is really not brand new. It's been around for a few years still, but his block f looking at art, but not with the defibrillator CRT pacemaker therapy. And this is in patients with. And this is the first time for the ejection fraction not below 35%. But its's patients who have need for pacemaker like with heart block who have an ejection fraction that's reduced but not severely reduced so less than 50%. So the patient comes in with heart block, which is about 800,000 people in the United States alone, and they're F is 48%. They don't have a defibrillator indication, but they have a pacemaker indication with the heart block. So therefore CRT pacemaker. So again, even looking at these people who are not necessarily symptomatically sick with heart failure when comparing by V pacing tojust RV pacing alone in an ejection fraction that's reduced but not severely reduced, we have a 26% reduction in mortality. That's mortality and heart failure related. Urgent care or visits to the hospital or to the heart failure special. Sort of. You is a physician taking care of somebody with with heart failure. So again, the newer trend or indications are offer this therapy to the less sick people who it's indicated forward to help prevent them from getting sicker. So what's new with the devices? What's happened with CRT device is the actual defibrillators themselves, and I'm going to focus mostly on defibrillators CRT defibrillators in this discussion because that's where a lot of the technological advancements have come from, or where they've been developers and within the defibrillators. Um, probably one of the things that stands out is that the newer devices have longer battery life that's important because it means less time into the less less opportunity for infection if we open the pocket to do a generator change. So these new devices air nearing about 10 years with CRT that's three leads two or three of the leads, always pacing. Um, some companies will tout a 13 year battery or 12 year, but we're approaching that 10 year mark for CRT. Were there with pacemakers already were there with some I C. D s, especially if they're not pacing. But where we're pacing the heart all the time with both bottom chambers or one bottom chamber. I'll talk about that in a moment. We're getting 10 years out of these devices, or that's the projected. Because some of these devices are brand new. We only have had them for less than a year that I'll talk about the other thing that stands out as new and devices are automated algorithms. What do I mean by that? These air algorithms that are programs that air that are built into the device is to ensure that we're pacing both ventricles. It's actually if we're not by V pacing 98% of the time, that means both ventricles pacing. 98% of the time. We actually increase mortality and morbidity with these patients. So we really need toe. Make sure that we're delivering this therapy that we've been planted in these patients. The automated algorithms can optimize atrial ventricular synchrony or timing and ventricular to ventricular timing, so these things are automatically programmed. If we program them on or off. We program them how we wish to program them toe optimize doing what's best for the patient with the pacing algorithms. One of the more newer things that's that's being programmed and being built into these devices is using physiologic sensors that trigger an alert to us that, hey, your patient may be going into heart failure, and we may be able to tell you that not only two weeks before it happens clinically, which is what we've had with the Thor Asic impedance measurement for a number of years now, but also maybe even up to 30 days out with some other physiologic parameters that are being monitored constantly by the device and then with the new technologies there added with other alerts that air that may be occurring to the patient and that then sends an alert to us. Your patient has reached a threshold. We're alerting you that there could be a chance they could be going into heart failure. So if we can get that information before the patient gets clinically sick, we can adjust that. Our heart failure specialists, all of us that follow these patients can increase their diuretics can make sure they're being compliant with their other medications. Make sure that their other rhythms are under control before they end up in the hospital and us trying to have to do that. So that's a That's a pretty, pretty significant advancement here. It currently only exists in two of the companies of the four, but as I'll show you, it will likely be coming soon for everybody. And I think the I think the other significant thing within the devices themselves is the development of Bluetooth communications ability. What does that mean? So we know from data on how patients do that are being remotely followed by their device and with the bedside or whole monitor to communicate with us and patients who are not. It turns out the patients who are not followed with remote follow up actually have more morbidity and higher mortality than patients who are being regularly followed and what these devices. That means we get a download every three months to let us know everything looks great or on a daily basis. If there's any alerts pro that have been triggered in the device arrhythmia more a fib, ventricular arrhythmias, even if no shock was given, Um, is there fluid overload building up? Do all those physiologic sensors meet up to say your patients reached the threshold where we think they're about to go into heart failure? So that's an alert that we would get. So having a patient remotely monitored adequately and thoroughly helps us take care of those patients so much better and helps them to do better in the long run. With their heart failure, Bluetooth technology has allowed that to happen much easier, much quicker. Download from the device to a patient's Bluetooth monitor. Either it's their cellphone, their smartphone that can communicate with us or a Bluetooth bedside monitor. It's much easier and quicker from the device to download to this and that T download Tow us. I'm usually be a wide fired cell technology. So again, enhancements to help patients and to help us in the clinics. So if we look at, there's four companies and I list them here because there is only four companies that make these devices. And what's interesting is there are common features toe all of the manufacturers that make the devices. And if you look they're equal across the board and the common features that basically what we need a CRT device to dio this is the basics. Most common things that we need a heart defibrillator to dio and all companies have that they have the ability. If you look across the top to tell us the timing from right to left ventricle, which is the best chamber, or which is the best electrode combination to pace from because we have options, there have techniques there in the second category to decrease inappropriate shocks. It doesn't decrease the strength of the shock, but it decreases maybe the need for the shot. Maybe the patient didn't need a shock to treat that non sustained ventricular tachycardia. Or maybe there needs to be a longer detection times so and trying to decrease shocks to patients modes to help pace people out of atrial fib relation. Everybody has some degree of that. All the devices store the data until it's download to us. How what's the heart rate? How many PVCs or people having how much atrial fibrillation are there having what is the device? Diagnostics are they eat real lead, ventricular lead and LV lead? Are they Are they stable? Do we get good sensing? Do we have good pacing? Automatic threshold? Checking all those things? All the electrical impedance is all that's trended, and we get to see that as well as the heart failure parameters. Air trended So we can see that as a diagnostic tool, the ability to anti tachycardia pace before delivering a shock. It's all there and all the devices and each of the company has now the ability to wirelessly communicate from the device to the bedside monitor and from bedside monitored us. So all that exists with all the companies looking at the differences now, and we look at the premium devices. There's some lower to your devices and premium devices, but let's look at the best of the best of the devices, and what you see here is that they still on the bottom row where it says common features. That's what we just talked about. So these features that you see there are color coded for each of the companies are actually the differences between these companies devices I'm not going to speak to which one I think is better or best. That's everybody has their own opinion and as the features and device program ability that they like and may choose. Based on that, some of you may practice in places where you're you have one or two vendors to use. Some other places have all four vendors, and sometimes that changes back and forth. But what's interesting and I want to point out here is if you look at where the most features are, if you look at the slide again in four or five years, it will look different than this slide. What do I mean by that? It's about a five year time span, at least when generations of devices change. So when new features come out and the FDA approves them and then they're put in, the device is it's about a five year time span before those changes can occur. If we look on the far right This is the one of the This is one of the most actually the far right two categories. This is these are the probably the two newest devices that have been released and heart failure, and you can see they have a lot more features. If we go back to the second category here under the Abbott Gallon device, this is the more recent before these. So next most recent was that that second category over Abbott Gallant the most recent was the far right of your screen. The far right two categories. Um, and it's there. These are all programmable features that help improve CRT response improve, alerting us to if there is heart failure. And what's interesting is when you have the ability to measure Thor Asic impedance, which is fluid buildup in the lungs. And if you look this dark blue, every company has that right. But what's different is only to the companies so far. Have the orange or reddish blood orange. I'll say category, which is the ability to notify us via an alert. If there's the possibility of our patient developing heart failure before they even symptomatically feel it. It's only two devices have that that's the Boston Scientific and Tronic device. But why say this slide will be different five years from now? Is that all these companies will likely have those features, because what happens is whichever company jumps ahead with a feature the other companies follow along because it's an important feature for heart failure, and it's something that makes them competitive. But again, the basics. All the devices have all these basics that we need these air extra features that either improve the CRT optimization. They improve the ability to alert us if there is worsening heart failure and they improve the communication with us via Bluetooth technology. Not everybody has that yet. The two latest companies have that Other companies you realize that the Boston Scientific device has been around for three years realize that the bio tronic device has probably been around for two years. So in the last 2 to 3 years, these are the kinds of differences that we see and will continue to see going forward. So let's talk about those physiologic sensors because that's a really neat technology boost that's happened here, um, in helping our heart failure patients. So if we look at the path of physiology, of congestion, of heart failure. And we look at the timeline Well, 30 days before somebody presents to the hospital with heart failure, they may have had a decreased cardiac output, and that may have increased in May have caused increased in left atrial pressure. Um, and, uh, that may change heart sounds. We listen for an S three. So the ability for the reverberations of the heart to be picked up by the device is now possible in one of these implantable devices. So we here in S three and that has three can become louder if there's where his heart failure. By day 20 the sympathetic nervous system activity increases and we see heart rate variability change. We see resting heart rate increase by 15 days. We start to see thoracic impedance changes because pulmonary fluid or a Dema is increasing, respiratory rate increases. People sleep more upright because it's easier to breathe. And prior to these current devices that tell us these other parameters are being met, that's what we had the pulmonary fluid and everybody opt of all core viewed other trans Jurassic impedance. All the devices have that as a basic feature now, but we're going back even 15 days before that with some of these newer features. Weight increases in less than 10 days before our heart failure event. The presentation activity decreases in symptoms worsen. But when you at all these pink alerts or sense are physiologic sense sensors being activated or measuring changes suggesting somebody's getting worth worse, then what can happen is this. Condemn Elop. A scoring system where an index is is, uh, developed or measured, and that index, once it crosses a baseline that you, as the health care person can provide. Okay, if they pass this baseline, I need to know about it. We then get an alert which can occur daily. Of this score is suggesting the S three got really loud. The heart heart rate went up. The Thor asic impedance changed. It sounds like this. Patients going into heart failure, and we call our patients and they say they know I'm not feeling bad, and then you bring them in or you look at them if you can, through video visit, which is difficulty Are their neck veins distended? Do they have a Dema eyes, their scale going up? Are they less active is a respiratory rate up because we get all that information and this alert, but we can then treat our patients before they actually go into a clinical exacerbation of heart failure. So that's a pretty neat new type of therapy with these devices so it can emulate a clinical assessment before we can assess our patients. There's multiple sensors that are added together, not just one type of measurement. Thes measurements are relevant to heart failure. Onda. We can personalize it for each patient set that that threshold differently for each patient. This algorithm was developed and validated initially in a 100 patients, but it's been used clinically in thousands and thousands of patients. Now, when we talk about the re mobile, the mobile remote monitoring our connectivity, the use of Bluetooth has really helped a lot, so patients can use their own smartphone toe automatically transfer this data from their device on a mobile app. Just a nap that they download actually, the hardest thing for a lot of patients that just remembering there app store password. But actually that app allow constantly running allows a patient to be a little more knowledgeable and involved in our am I being monitored so we can see there's battery longevity of their device. There's the implant date the device name serial numbers are clinic information at the patient's disposal on that app. They can use this app to track their own vitals. A lot of patients wish to do that. This app will help track activity on a daily or weekly or monthly basis for a patient. The clinic information is there if they need to get in touch with us. Probably really important is one of the biggest questions patients have. Um I connected with you is a clinic, and we can see that they're connected by that green check mark up on top. They can verify that they're connected. They can verify, has their transmissions gone through? They sent a transmission. For whatever reason, then we as a clinic don't always have the time to call back, saying yes, we got your transmission. They could have this at their disposal right there. They can log their symptoms, weaken, see their symptoms, and they can log those, send them to us, or show this. Show them to us when they come into the office. And there's educational materials on here, where patients can go and answer their questions. They may have that comes up about their device, but it's really good for the patients to help them. But it's also really good for us for the clinic, because if we think about all the thousands of patients were following with pacemakers and defibrillators and, UM, CRT defibrillators and pacemakers and all the devices and implantable cardiac monitors and all the patients we follow, that's a lot of patients, and the staff is really busy. And if you look at trying to increase that clinic staff and how that clinic is run their efficiency, realize that 40% of all device clinic called burden being patients calling into the device clinic with a question fall around four major topics. And having a Bluetooth enabled smartphone is that remote monitoring device. Those four again responsible for 40% of the calls into the clinic, which we may not have time to answer back, which is a frustration for patients, um, are answered by having this one transmission status, the APP states and clear language that the status of each transmission your transmission went through period connectivity issues allows the patient, the opportunity check. Are they connected at any time, day or night? And there's questions around discount there. Being disconnected things tells the patients not to disconnect the app, but it reminds them to reconnect if they're disconnected again. The clinic staff could do that after a few days or a week. But that's the patient not being monitored. And we're talking about heart failure, efficiencies and physical physiologic measurements. We want to know that without a week going by and some clinics, it's even longer. So the patient basically helps the patients to stay connected, and patients call with questions, which is human nature. They have questions about their device. What this means, what that means. Ah, lot of these questions are answered right on the APP. They could go there and read that and answer those questions for themselves so that that's a really neat feature to help our efficiencies as well. So let's shift gears really quick and say What's new? Okay, we got the devices. Here's the new things in the devices, but what's new with leads, right? We've had the same leads for some time. But remember the first leads were actually pacing leads that were put into the vein. And so we've, you know, the biggest Advent. Our biggest improvement in Leeds occurred probably around 2000 and 10 and a little bit before that, where instead of a bipolar or two electrode lead, we have a four electrode lead that allowed us to be able to have a lot more options for pacing. Thes with Quadra Polar lead You could see a little electrode here. 1234 This was the first lead actually made by ST Jude. Then years later, Medtronic came out with their lead. Uh, they're just different curves to help the curves or to help the lead stay stuck in the vein as much as possible. But they're electrodes. Air 1234 and 1234 They're labeled from the tip back distal one m two m, three proximal four. And this is another company that has their straight lead, and they're spiral lead with a longer separation. So the quadra polar leads were really helpful. This is a life. Were event changing were game changers. This is a coronary Sinus venogram. Where we inject contrast, this is a catheter up into the vein selectively. Here. The coronary Sinus is back here. But this injecting injecting this vein selectively and it fills all the other veins. Remember? I said initially, the veins are all connected. So any of these air good options we would choose. And so we place a Quadra polar lead. This is a case I did Where you can see the atria lead the ventricular I c d lead. And this is the LV coronary Sinus, cardiac vein pacing lead electrodes One, 23 and four Out. In that vein, the curve of the lead helps the lead stay into the vein. This is an Elio projection, Elio tells us. Are we on the lateral wall? Same patient, Just a different view. This was really a game changer. But what's happened? What's come out is you know that this is great. But sometimes we have to place the lead all the way down into the distal tip of the vein to make it wedge there so it doesn't move or pull back. But with the four lead electrode Lee weaken pace here from the more proximal electrodes we know from that made it CRT trial. If we pace from the Apex with this left side of lead that can actually make people's heart failure worse. We want a lot of separation between our RV lead and our LV lead, and we can pay from these four different vectors. So what's new in the leads is now an ability to actively fixate that leads so it doesn't move or slip out. If you look here, this is that same quadruple or lead 1234 But if you look here, there is now an active fixation helix like a screw to screw the lead in. Here it is on the lead, and as it turns out, it comes out. About a quarter of a millimeter turns out in the studies, looking at where the veins and the arteries lay next to each other. How close are the most of they were not more than a millimeter, so that he looks, comes out a quarter of a million meter to not go out and and pale the artery next to it. With the quadruple or lead, we could put the lead all the way into the distal part of the vein where it would stick, and then we could pace from up here away from the apex. With this active fixation lead, we can actually put the lead much farther up toward the base and the mid ventricle because pacing from the base of the heart, the top of the heart and the mid ventricle is much better than the apex. Just because we know made it, CRT said. If you pace from the apex, you could cause more harm so we can place the lead here, maybe in a bigger section of vein, and then actively fixate it so it lead doesn't pull out. The worry is, if you're not far enough into the vein, where it's kind of stuck in there, the lead can fall out or back out. This is a little video just showing how it fixes there and watch. The lead will be counterclockwise torque you can see right here. Coming up the top is the tip of the helix right there. The lead is being rotated and then grabs onto the vein wall and locks into place. Now you can reach and pull it out. It's not that strong, and the little helix will spring up. And so you're not tearing the vein open. If you just do that. But this is made toe. Have it fixed right to the side of the vein. There. If you go the next slide, I seem to be stuck there. Yeah, so this is just to show the helix. It's about a quarter of a millimeter distancing of a millimeter between the vein and the artery. You can see that it really just comes up to the wall of the vein and does not go near to where an artery and vein and artery are always typically together. It was gonna finish up by talking about, you know, the clinic. We talked about identifying the right patients. We talked about the new types of technologies within the devices. We talked about the new incidentally, that active fixation lead. We just got approved this last year, really, within the last 6 to 9 months, which during coverted and so we we've used it. It has its place. And if we get to our case presentation, I have a case presentation to show on that. But what else is new is realizing? Are we buy be pacing all the time. Was the lead placed in the right place. People who are not responding, especially there, who were focusing on in the clinics. How can we use their device to get them better if they're not better after they went through it? So we have to ask ourselves lots of questions. Are medications optimized? Is the patient by the pacing? 98% Is the L V Leeds still working? Is that capturing? Did it move? Are there any other co morbidity? Is that air worsening things here? Anemia, renal failure, atrial fib, relation? Do we need to optimize the timing better between the atria and ventricles or between the ventricles? Is the LV lead in the optimal position? And we need to look at all that. And that's tough to do all that in an E P clinic, or even in a heart failure clinic in the device clinic. Well, we decided to have a multidisciplinary CRT clinic where we have all those disciplines together at the same time in the clinic seeing the patient and they go through echo and chest X ray and blood work and everything right before we see them. And we have the device representatives there and we are working to to manipulate and to re program the devices and make sure everything else is lined up for giving them the best CRT response. So usually 4 to 6 months after implant will do. An echo will make these measurements. I will be there or Nicholson will be there. Typically, the two of us do this with the heart failure doctors, and so well, look at all these parameters, the heart failure. Doctors will look at all these parameters. And if you look or addressing all those issues between the two of us, and if the TRT, their CRT responder and they end up doing well, fabulous, that's great. If not, we know we've tried everything we can possibly do to help get them better. And then we need to go down other avenues for assessing them. But in our first year of doing this clinic every other or every few months, you can't do it all the time because it's a lot. It's labor intensive. We've made changes in practically every single person that's come through to improve them, and we've seen a lot of improvement in these patients. Ondas faras Future What I think is coming in the future, maybe mawr leaderless technology like Dr Olsen talked about to somehow use that for CRT, but also other types of techniques and technologies to assess who's gonna be the best patient. And where's the best place if we have to veins going to the side wall. Which veins should we be putting this lead and we try to do that based on the distance away from the right ventricular lead. But if we have technology that tells us hate, this is where you should be putting it and we can use that technology during the implant that's gonna help us, even mawr, to be optimally treating these patients.