Thank you to Atric here, it's always a really good conference and I already feel like I'm getting some of the information I came for, which was to hear a little bit of the early data about PFA. But I'm going to talk a little bit about heart team collaboration. I'm going to move quickly through some of my early slides because I think you've heard a lot of this already about the poster wall and just try and really focus on where is our room for collaboration and how do you kind of approach the EP if you're a surgeon or if you're an EP, how do you approach your surgeons to say we want to start a program like this. So we know that the hybrid candidates are going to be the more difficult patients. These are going to be the longstanding patients, the ones with more structural disease, possibly people that have failed a few catheter ablations or for some reason maybe somebody who just can't take anticoagulation and really needs a left atrial appendage clip. So these are difficult patients and I think that's the room for sort of starting the conversation is to sort of say, you know, EP, you're really good at the paroxysmal patients and that's not the space we're talking about. We're talking about collaborating on these more difficult patients that it's harder to achieve success in and what would we have to offer if we tried to work together. And this is an old slide of Kevin's. I think Kevin's gone so he doesn't know I stole his slide, but I'll tell you I'm stealing your slide. But basically, you know, we're good at the veins. So the fun of this collaboration is that surgeons need to come take a look at maps and I need to come down to the OR and take a look at what I'm trying to see when you're doing surgery. I feel like you guys do a better job seeing stuff when you come to the EP lab than I do when I go to the OR. I just see a lot of red. But basically, if you're looking at these maps, we're looking at voltage. We're looking at that voltage extending into the veins and you can see that, of course, the EP can do a great job on those veins. But what we traditionally really had struggled with was the posterior wall. Now we've gotten a lot better at that. It doesn't work for everybody. Just doing veins or even adding the posterior wall, as we've hoped for, just hasn't really engendered the kind of success that we were looking for. We know that the posterior wall is an incredibly active area. It has an old slide, but thousands of different mechanisms. You've heard us talking about GPs, about focal triggers, about rotors. So targeting the posterior wall makes sense, and yet somehow it's not really panned out for the EP doctor as well as we sort of hoped. We had a lot of observational studies until we had the CAPLA study. Our other issue was always the esophagus. So esophagus being right behind the left atrium was limiting and very few people can really survive a fistula. So one of the developments that I've used with some good success is this cooling esophageal balloon. So it's really just really an irrigated NG tube that we hook up to a blanket cooler, and it lets us cool the esophagus so we can ablate the posterior wall much more freely. That did free us up to do the posterior wall, and so we were again very enthusiastic that that would take care of our more advanced cases of AFib, and lo and behold, as you've now seen this slide multiple times today, it didn't. Targeting the posterior wall with catheter ablation in addition to the veins didn't seem to increase our success rate, and here's that data showing posterior wall in addition to veins really no statistical difference. And the reason is this. I really like this study. So this is a study that's showing us muscle planes, muscle layers, looking at the septopulmonary bundle and the septoatrial bundle. And as we come around towards the roof and dome area of the left atrium, there is extraordinary separation between those two layers. If you look at the histological specimen in the middle of the screen, you can see encircled in yellow, kind of an echolucent area. And looking down on the bottom right of the histological slides, you can see that there's a huge plane of fat, and fat's just a sink. So we can ablate endocardially and get fantastic posterior wall isolation and still have a completely active epicardium. And so this is where that concept of sandwiching and going both endocardial and epicardial makes sense. This was an interesting slide for me, looking at different maps or different ways when we think we've achieved our isolation on the posterior wall, different types of activation patterns that we see. So in the very first slide, you can see focal activation. So in this first example, A, there's a small area that's just like an island unto itself. Just in the middle of the posterior wall, something that appears to break out even when you have a roof line and a floor line. And so this is an epicardial connection coming directly in to the endocardium. The second pattern here, B, is where we get a leak. So that's where we map along that posterior wall. We can see a gap in our roof line, and we can see current kind of streaming through that gap. But the third is sort of the most dreaded pattern. And this is where we've ablated and ablated and ablated across the roof. We have what appears to be a good line of block, and yet activation is pouring down from the roof to the floor like a wave front. And this is all epicardial. So we can ablate all we want. We can use new strategies, and we may not be able to eliminate this sort of activation pattern in the posterior wall. So we look for these gaps. I would say that the roof is far more likely to have a gap than the floor. At the floor area, there is much less fat separating these bundles. But we get a lot of gaps up by this roof line, and then, of course, others have talked today about the mitral line. So quickly, just looking at some maps, we don't do much CONVERGE at my center. So I had to borrow a couple slides. But when I originally started doing some hybrid cases and did CONVERGE, we'd have what we called this dog bone shape, where because of the pericardial reflections and the limitations of where you could get that catheter, we would have some viable tissue on the roof and floor that could be touched up by the EP afterwards. But it wouldn't appear to be a full posterior wall isolation like we're used to, but very simply touched up by adding just a few lesions. And this is with the other mapping system. Again, you can see kind of a patch up on the posterior roof that could be easily touched up. And again, more examples of this. The reason I'm showing these is I think the area for collaboration is in sharing these maps. So for years now, I've worked with Gann Dunnington. I've had the opportunity to work with Armeen Kiyankui in the back. And we do something where when we map our cases, we send out a blast text to everybody that's on the team so that everybody can see where the gap was, where the lesion was. And we then have tried to have quarterly meetings in which we would present these maps and talk. And so from time to time, if the surgeon was making a change in their surgical approach, we could get a look and say, you know, ever since you started using that different clamp, we're consistently seeing a leak here by the roof, by the right superior pulmonary vein. And we could adjust the strategy. So I think there's something very team building about sharing the maps. So we share the maps after every case. And we have a goal. Don't know that we're always doing it, but have a goal of at least quarterly sitting down and going through as many maps as we can together as a team and discussing where we're seeing leaks. We also have had really frank discussions about the mitral line. Interesting to hear Chad talking about his Y lesion. We've all worked with the same surgeon. So different strategies about how to approach the mitral line. Should we touch the mitral line? Shouldn't we touch the mitral line? And if we're going to, where is that line going to be so that I know where to pick it up when I get into the EP lab? So I think the shared map experience is really key. And then for me to go to the OR, not so much that I understand surgically the view as well, but that I can see the difficulty of some of the angles that you're trying to approach. The one before, it was showing a leak across the roof. Some lesions were made across the roof. And now the leak switches to coming up from the floor. Additional lines are made across the floor. And we finish the isolation. So this sort of feedback I think is really helpful to the team as a whole so that we can all kind of work together to create the perfect poster wall that we're looking for that I don't think with any technology, including it sounds like PFA, we're really going to be able to get there without working together with an endo-epicardial approach. So I think being curious, brainstorming about different ways to approach it, going into each other's domains, and consider doing a joint clinic. That's another thing we've done at St. Helena is we see all AFib together. So surgeons and EP docs. We're seeing patients that may have been referred specifically to the surgeon or to the EP, but we collaborate. So we can come out, talk to each other, pull them into the room, the blast texting. And then thinking about how you're going to track your results. And that's been kind of a little bit of a tough nut to crack. Other people have talked about doing the ZEO at three months and then at one year, some sort of a patch monitor. We've tried at times to try and get as many patients as we can with an implantable if you're planning on publishing. And I think to be able to talk about AFib burden rather than the HRS definition of 30 seconds of ATAC is probably really helpful. And I think the more we collaborate on all these cases, the better results we get. As I've heard others say, working together in the hybrid area kind of has allowed us to also get involved with a lot of the concomitant cases. So that's been really interesting to go back, if somebody's had a Cox maze, and be able to map those cases and see what we find. When you're only able to do a limited number of lesions and some sort of an open mitral procedure, we can map and finish those up. So I think once you start collaborating, you discover a thousand more ways that you can collaborate and it just builds on itself.

heart team collaboration

electrophysiologists

posterior wall ablation

cooling esophageal balloon

endo-epicardial approach