All right, thank you very much. So I'm very happy to be here. So I'm going to be talking mostly about our experience here at UCLA with the extracardiac Fontan. I don't have any disclosures other than, as was mentioned, I'm an electrophysiologist, so I think some of the things I'm going to be talking about may seem a little simplistic from an interventional standpoint. So as has been mentioned, sinus node dysfunction is quite common after the Fontan operation. For patients who have extracardiac Fontans, the incidence of sinus node dysfunction the first decade or so after surgery is somewhere around 10 to 15 percent. That's been shown in meta-analyses and other studies looking at the follow-up of these patients. And we know that sinus node dysfunction is detrimental for them. When you have atrial contraction against a closed AV valve, there's an increase in pulmonary venous pressure, which raises the Fontan pressure, and it has been reported as a reversible cause of Fontan circulatory dysfunction, including PLE and plastic bronchitis. So in that context, I think sinus node dysfunction has been what we've seen most frequently in this patient population, and I want to go through just a couple of cases talking about how we've dealt with this in these patients. So our first case is a patient with unbalanced AV canal that was transferred from another hospital, really for SVT, came to us on multiple anti-arrhythmic drugs, including amiodarone, infusion, procainamide, and Esmolol, and was intubated, actually was very sick, was grossly anisarchic, was intubated, sedated, had multi-organ failure, and was on dialysis. And had a prior epicardial pacemaker for atrial pacing that had failed, and when we administered adenosine for her SVT, it terminated, but she had profound junctional bradycardia, and after a few beats, she'd go right back in SVT. And so it became clear that the underlying problem was her sinus node dysfunction. This is back in 2013. Having at that point done EP studies on these patients and used the pulmonary artery for recording and pacing during EP studies, we thought it would be reasonable to try to pace her atrium remotely from the PA with a temporary system. So we screwed in a Medtronic 5076 lead, we actually first showed that there were atrial signals in the PA. We screwed in a Medtronic 5076 lead and externalized it through the IJ, and paced her, and we were able to get her out of her arrhythmia. She was extubated, weaned off her inotropic support, and did remarkably well in the week following this procedure. So we decided to take her back to the lab, and we did a puncture through the IVC to atrial overlap that we commonly use for these patients to ablate her SVT, which was AVNRT. And then at the same procedure, we decided to put in a permanent pacing system for atrial pacing. And so the technique is very similar to what's been described so far today. I'm not going to go into a lot of detail here, other than to say we used a BRK needle and a select-secure sheath to puncture through the PA into the left atrium, and then basically used biplane fluoroscopy with the ablation catheter as a reference to guide the puncture. And at that point, we screwed the lead in, we tunneled the lead over the clavicle and placed the pulse generator in the right infraclavicular pocket. The patient was started on Coumadin, she went home about a week later, and did really well in follow-up without any recurrence of their SVT or problems with her pacemaker. So it went really well. This is the TEE during the procedure, this is the pulmonary artery here, and then this is just showing the lead into the left atrium, and it was screwed into basically the base of the appendage here. And that was published previously. Now, what we've noticed since then, though, is that, and I think this has been mentioned in this series of talks, is that there is a real concern for systemic thromboembolism and stroke anytime you have lead material in the pulmonary venous atrium, and it has actually been reported after this approach. And so since this original procedure, we've modified our technique to avoid putting lead material into the cavity of the pulmonary venous atrium. So the next case is a 30-year-old who came to us with multiple surgical pacemakers that had failed due mostly to infections, had multiple thoracotomies, and essentially was not considered a surgical candidate. She also had atrial flutter related to a prior Fontan conversion operation. Her CT scan is shown here. As you can see, there's nice overlap between the pulmonary artery in the left and the pulmonary venous chamber. And essentially what we did in this case is to place the lead through the PA, but we affixed the lead to the epicardium of the morphologic left atrial wall. And we're able to get relatively good pacing and sensing characteristics from the lead in the epicardial approach here. And otherwise, the procedure is very similar to what I mentioned previously, other than we stain the tissue as we go through, and we stain the epicardial portion of the atrium, and don't go any further than that. We don't enter the chamber. This is what it looks like on one of our 3D maps. We also, as I mentioned, we did a flutter ablation here, and this is just showing the final lead position, and essentially the dome of the left atrium here. Similar, not too dissimilar from, you know, or too remote from where a surgeon might place an epicardial lead for these patients. And so then we recently just published this. The other group that's doing this is the group at Vanderbilt, and we have a case series now that is in the Journal of Cardiovascular Electrophysiology. So basically, to conclude, the transpulmonary puncture was our initial approach, and we've since modified that to epicardial lead placement, mostly to prevent thromboembolic complications with this approach. Thank you.

extracardiac Fontan procedure

sinus node dysfunction

remote atrial pacing

temporary and permanent pacing systems

modified epicardial lead placement technique