Sabrina D. Phillips, M.D., a cardiologist specializing in adult congenital heart disease at Mayo Clinic in Florida, presents in the Advanced Heart Failure Grand Rounds series on heart failure in the adult with congenital heart disease.
So uh good morning um everyone uh welcome again to our heart failure Tuesday. Like the series Today we have dr Sabrina phillips. Dr phillips is a board certified adult congenital heart disease specialist providing care in the adult congenital heart disease clinic here at the florida campus. She is an expert in a cartographic assessment of complex congenital heart disease. Her research interests includes clinical research involving patients with congenital heart disease and she is also involved in medical education at the local and national level with the goal of increasing awareness of the unique challenges being carried for the adult with congenital heart disease. So with no further introductions at Sabrina take take over. Thank you for that introduction one. Um I'm really happy to be here with you guys today. I have to say it was a little anxious coming in because this is a very sophisticated group and audience with vast experience caring for patients with advanced heart failure. But I wanted to share some thoughts on the unique challenges of the patient with congenital heart disease, who has heart failure and maybe introduce some, um potentially different concepts about how I think of my patients who are not thriving or who are not meeting their needs from a cardiac standpoint. So just to step back for those of you who may not be um well aware of the scope of congenital heart disease, it's actually not a rare patient population. When I sometimes when I start to talk with people and tell them what I do, they're like, well, where do you get any patients from? And the truth is that unfortunately, this is a common problem because cardiac Um congenital cardiac disease is the most common birth defect and that occurs in about 1% of all live births, which roughly translates to about 32,000 new cases of congenital heart disease every year in the us. And we have become thankfully very good at caring for this patient population. And so if you're born today, even with the most severe forms of congenital heart disease, you have an 80% chance of survival to your first birthday. And if you survive to your first birthday, there's a 90% chance you're going to be in my clinic and then potentially later in the advanced heart failure therapy Clinic. So most one year olds will live to adulthood. There are now more adults in the US with congenital heart disease than Children. This is an adult problems. So it's important for adult providers to be aware of this and it's over one million adults right now who need to seek care and specialist centres. Just a little historical perspective. You know, we have made rapid advancements um back from the thirties and forties when you really didn't think you could operate on the heart, all of the congenital heart defects that were taken care of before the 19 fifties were things that were outside the heart. So P. D. A. Ligation, the Bt shunt. And there's a wonderful movie about the development of that at the Hopkins Center and then co optation repair. But then you see the fifties we explode into inter cardiac repair, starting with VSD. Then going on quickly the tetralogy of flow and then um mustard and sitting around the same time to different surgical centers. Thought of a way to repair complete transposition using complex atrial baffling. So we call that an atrial switch then are fairly quiet since these techniques are being improved and surgery is being improved. But then in the seventies, french surgeon Fontane comes up with a surgery to pal E eight, the patient who has a single ventricle circulation. And we're going to spend a lot of time at the end of this lecture talking about that. And then we don't have much advancement till the 80s when we see our last two big surgeries come onto the scene which really revolutionized care for most complex patients. And that was the treatment of hypoplastic left heart syndrome, which before the 80s was universally unfortunately fatal unless you could get a neonatal transplant. Norwood comes up with a procedure to help those patients. And now we're seeing those patients in adulthood, which is quite gratifying. And then we refined the treatment for complete transposition with the arterial switch, which I'll talk about briefly coming up, which allows patients to hopefully do better longer because they're going to have a left ventricle supporting the system in circulation. So we're really still in Pioneer mode for these patients. You can imagine if you were born in the late 80s, you're just now really becoming um an adult. We're starting to see the fruition of this work as we're learning more and more about how these patients may present with cardiac difficulties. So patients with congenital heart disease, they are for the most part palley ated not cure. There's, you know, we've tried to treat their lesion, but when we look at how do they do in terms of exercise and just kind of using the currency of peak vo two, which I think we're all very comfortable with thinking about that in terms of patients, um outlook and abilities, We see really somewhat sad outcome with patients with congenital heart disease. These are grouped patients with different kinds of CHD and if you look at age matched controls. So this these are the young patients that they're younger with congenital heart disease, average age 33 and then the heart failure group who came from a advanced heart failure center To be compared, they were averaged aged 59. So when you look, especially at New York Heart Association Class one, if I have a patient in my clinic, I say you're doing great, you're class one. Look how much lower the achieved peak vo two on objective testing is than their age matched controls. That's not true for the patient who has traditional forms of heart failure, who is new york Art Association Class one. We compared to their age matched controls. They're a little worse, but they're not significantly limited. So we realize that our young patients start out a little bit behind the eight ball, and then as they progress, they look very similar to our other heart failure patients, but they're dropping off their peak Vo two achievement quite significantly compared to their peers. So just like in acquired heart disease or traditional forms of advanced heart failure, peak Vo two is important. I get a lot of these cardiopulmonary tests um to follow my patients and it does predict clinical outcome, which is not surprising. We know this is a pretty good marker and a tool Um and that we can see that patients who have congenital heart disease have very low peak vo two is less than 15, um do very poorly in terms of freedom from hospitalization or death. So it's not the same measurement, potentially is what we utilize for other patients, but we know that it matters in lower votos are important. So the adult with controllable heart disease may face sort of unique forms of heart failure or lack of cardiac efficiency, including right ventricular failure. When the right ventricle is in the systemic circulation. So our patients with um hypoplastic left heart syndrome, we talked about the great advance. Their their left is a single ventricle circulation with the right ventricle. But we do have to ventricle patients um who have a systemic right ventricle. And that's a unique problem because remember the RV. And the L. V. R. Not just right in the left hand glove there like a glove and a mitten. They had completely different jobs to do. They were designed to do something different. The right heart was never meant to pump two X. Increased after load. It was meant to be this low after load pump with good volume sensitivity and so its adaptation to be in the systemic circulation leads it unfortunately too early failures you get um hypertrophy and dilation to try to keep up with the demands. It's just like filling the sub pulmonary right ventricle is fairly common in our patients stay with tetralogy who are often left with significant valvular heart disease that produces a volume loading on the right ventricle thankfully, I think we're recognizing this better and we're not letting patients get to the failure stage, but the forms these forms of heart failure, I'm not going to spend a lot of time on because I think that they lend themselves to the more traditional approach. We do what we need to do for sub pulmonary system ventricular dysfunction, utilizing the medical tools that are advantage, including even a mechanical support options. But what I want to draw our attention to mostly in this talk is maybe something we don't think about as often, and that's diastolic dysfunction or severe noncompliance of the right ventricle. How that can lead to patients with um congenital heart disease to have low cardiac efficiency, poor exercise tolerance, and how difficult that can be to address and to recognize because in the ecolab nobody is thinking about diastolic dysfunction of the right ventricle. We're talking about E to us and the left heart. We're looking at all this stuff, but nobody's really thinking about the RV because we're so used to being a compliant pump. And then this may be a little unfair to lump in here. But I think it matters. And so a lot of my patients are failing to thrive or doing poorly, not able to achieve the exercise capacity they want because they can't deliver their needed oxygen content and that several things can cause low oxygen content delivery to the periphery, including inability to just oxen ate your oxygenate your blood. You don't have a good source of pulmonary blood supply. Maybe you have a good source of pulmonary blood flow, but you are shunting across an into cardiac shut right to left. So you're mixing your blood and you're not delivering things well and you're putting a strain on the sub pulmonary ventricle. We'll talk about some cases of that. Or maybe you have other reasons to not deliver oxygen content. Like you're anemic. So we're going to look at some cases I think illustrate the diastolic dysfunction of the right heart and this failure to deliver oxygen content. I think kind of cases are a good way to introduce these concepts and they're going to end today. Just a little bit more didactic, not case based because I want to talk about some of the complexities of the single ventricle um patient and how they may present to us with heart failure and some things to think about. And I think instead of going off on various case reports, it's better to just talk a little bit more mechanistic lee. All right, so right heart failure. Just as I said, systemic right ventricle, we're mostly seeing that in the general population in controlling corrected or l transposition of the great arteries that patients who uh maybe not have never had any surgery. But this is they've got a systemic right ventricle. But then the complete transposition with that old atrial switch, we're not seeing that too often because remember the arterial switch came into play in the mid eighties. And now we're seeing those patients do better with a left ventricle. Um Really not much to say here. We don't have any data. You know, there's like these like Terrible studies that are 15 weeks along with crossover and they look at a video to them. Like these inhibitors don't help you like, well, 15 weeks. That's not a very long trial. But I just basically utilize traditional guideline directed heart failure therapies for these patients. Um because we have to do you know what we have with our toolbox. So let's now go into these other forms diastolic, right ventricular dysfunction. So the right ventricle were so used to being compliant. But if you've had a lot of after loading the right heart, maybe you had PS or branch PS that provided after load. Or maybe you have abnormal pulmonary vascular resistance long term the right heart is going to become noncompliant. And here's some of the things that I look at in the echo lab. So this is a patient who had a tetralogy of follow with a lot of outflow tract obstruction. It was relieved in childhood. Um Now they actually have severe pulmonary valve regurgitation after their surgical intervention, which is common. But I want to draw your attention to this Doppler finding. So for those of you who don't read echo, we're looking at blood flow out the pulmonary valve essentially in the R. V. O. T. And this is sisterly right here. So this is the blood flow that's ejecting while the heart, the right heart is contracting and sisterly. So we should really see in a normal pattern this systolic forward flow. Then if there's some regurgitation in diastolic, that's this time period here. If you guys can see my little hand cursor, I hope on the screen, um this should be all above the baseline, going back into the ventricle. But look at this interesting pattern. I see what looks like inflow. If you're used to looking at trick us peter mitral inflow and diastolic, it looks like this. But folks going out the pulmonary artery. So what's happening is the RV is so stiff that as the right ventricle tries to fill through the troika speed valve in diastolic, it's increasing the pressure enough that you can just drive flow right across the RV outflow track. So this is a very non compliant right ventricle when you see this and we see this quite commonly. And what is hard for these patients is all of our mechanisms to say when should we should replace. Regurgitate pulmonary valve are based on the RV dilating because we're saying, okay, that's when the RV is not handling the volume load. But these patients can maybe not dilate very much because the RV is very non compliant, very stiff, verify bra tick. So we're not seeing that nice ventricular dilatation but they're very limited in their exercise capacity and it's just because of this poor efficiency and poor compliance. We can also see changes in the hepatic vein flow that lead us to understand the RV is noncompliant. And this is if the patients in sinus rhythm, you wouldn't see this if they were in atrial fibrillation, but when they have atrial contraction, if they get this big reversal in the hepatic vein, that's telling you that the ari pressure is very high and we're having some difficulty here. This is synonymous for those of you used to looking at the left heart diastolic parameters that this would be like a big a wave reversal in the pulmonary vein. And so this is very synonymous and we see this often in our patients who had had severe PS, we see it also in Eisenmenger syndrome, and this is just another marker of inefficiency of that right ventricular circulation. Well, the problem is what to do about it, just like left heart diastolic dysfunction. If we had a loose a tropic agent that would be great. But unfortunately usually this is because of fibrosis and there's no going back sometimes from this micro scarring. We don't have great lucy tropic drugs but we can do just like we do in the left heart we can prevent volume overload slow the heart rate so we can improve building times. And then I'm quite interested in these last two drugs um how they work potentially at the cellular level not just for their diuretic properties for many years. Felt that al back tone um clinically has been very helpful in my patients with a very stiff right heart. Uh And so I'm a big believer in this part of our guideline directed medical therapy. As I'm sure all of you I think I'll dock tone is kind of a unsung hero. I'm now more and more intrigued with the S. G. L. T. To type drug. I think that that class could be very helpful and an early clinical use for me in my congenital heart disease patients with right ventricular dysfunction. I've had a fairly good results now of course that's a little bit of anecdotal medicine right now but I think we're going to get more and more information. So I'm very hopeful that maybe this class a drug is going to give us a new tool in our toolbox for treatment of this complex problem. Well let's look at some cases now that sort of encompass these ideas of a stiff right ventricle, poor oxygen delivery and maybe how we can think about these patients and how to approach them. So this is a patient. Um I did not see him here at Mayo Clinic. This was when I was at the University of Oklahoma. He was a 60 year old man. He came to the E. D. Actually for a fairly minimal complaint. He um had a had a little upper respiratory tract infection. But he people freaked out in the er because he was de saturated and they were like oh my gosh you've got acute on chronic respiratory failure. You must go to the Miku. And so here's this guy who walked into the E. D. With some sniffles and now he's in the Miku diagnosed with severe COPD which has never been diagnosed with. And his sats were 80. And first they put him on high flow nasal cannula and they didn't improve his sats. And then they put him on bypass which he was pretty unhappy about as he sat there uh and it didn't improve as sad. And so they called us up to consult on him and When you talked with me had a scar on his chest, you're like, Hey, what's that all about? And he said, Well, I had severe pulmonary valve stenosis and uh at age 30 I saw a surgeon and he said we should just take out the pulmonary valve to believe your outflow tract obstruction. So they did that and he didn't feel a lot better. He said he had been pretty active. So he just decided not come back to medical care is like I went through this big surgery and you took out my pulmonary valve and I feel about the same. So he's been trucking along for another 30 years. But now in this setting of a previous severe outflow tract obstruction and now obligates severe pr so here's what his trans esophageal echo looks like. I apologize for the quality of this, but I think it gets the point across so you can see here that the right heart is huge. Right hearts dilated. The trikus paid annual list is dilated and the troika spit valve, they're not touching each other so we know there's going to be severe try custard regurgitation before we even put on the color. The system like functions pretty well preserved of this ventricle. And so often again that's all we think about. Systolic function is good. Um Look at this picture. The right atrium is big and look at the righty trail or the atrial septum, its Boeing continuously to the left. So I know my right atrial pressure is almost always higher than my left atrial pressure. Now normally they're about equal with the left atrium winning out. Of course not the case here. This thing is not moving much and not a surprise that TRS directed right at the atrial septum. It's severe TRS coming back there and here is a stretched P. F. O. And all the shunt is right to left. There was severe. Pr didn't show that because it's obligate that was there. Um So I read both the trans thoracic and the trans esophageal echo. I said well there's wide open pr not unexpected, severe tr with annular dilatation and a stretched P. F. O. And he's hypoxic or D. Saturated more appropriately to say because he's got a right to left shunt. And I said well we just need to call our cardiac surgeon and we should think about a pulmonary valve replacement and bicuspid valve repair or replacement enclosure of the P. F. O. And um the Miku staff. I thought I had lost my mind. They're like well this guy has a right to left shunt. He's got Eisenmenger syndrome. He clearly has bad pulmonary vascular disease and I said no, I suspect he actually doesn't have bad pulmonary vascular disease at all. And looking at several eco parameters and having a lot of gray hair, I knew I was going to be right about this. So I was going for C. And most everybody else was going for A or D. In the Mc you that day, just worried about this idea of how can you shunt right to left? Uh Well here was his calf data. His pieces like pressure was 23 PVR was very low 230.9. Would you know this guy did not have pulmonary vascular disease? He said, well how can you shut right to left while remember you can have a right to left shunt in the absence of elevated P. A pressure, especially at the atrial level because the atrial level shunting is a diastolic phenomenon are a pressure and low pressure are essentially related to diastolic parameters of the ventricle. So of course if you get pulmonary hypertension you're going to increase pulmonary diastolic pressure. RV. Diastolic pressure and ari pressure eventually. So yeah if I've got pulmonary hypertension I'm going to shut potentially right to left but I can do that without systemic hyper or systolic hypertension and just having diastolic noncompliance in specific settings. So think of it like this if you're more of a graphic person. So when we think of what does the tracing of um basically pressure look like in the RV. And the R. A. Over the course of the cardiac cycle this would be pretty normal. We have these low ari pressures. We have the um a wave. We can have a little wave out here but most of the time we're just following right along diastolic pressure of the RV. Of course it has nothing to do with the systolic pressure. And so in this case was severe tr if I keep the systolic pressure of the RV the same but I make the troika spit valve regurgitation. Look what I do to the ari pressure tracing As we get to the end of sisterly. I have an increase in ari pressure and all it takes is a little bit of difference between the ari and the L. A. To shut. So in this case you could shunt right to left and have no evidence of RV. Or P. A. Systolic hypertension. What do they have a case like this? Poor guy. He's not he's shutting almost all the time. And that's because he had severe RV diastolic dysfunction. He had 30 years of severe outflow tract obstruction. This RV had tried to compensate for that and now it was a non complaint RV. But then we volume loaded it in diastolic from two sources. We gave it its inflow which it meant to deal with. But now Pr was also loading it so we increased that diastolic pressure of the RV. So we increase the R. A. Pressure without changing the systolic pressure. And then we gave them severe tr further increasing that. So this is the case where we were at and this is a unique case of someone who was not doing well because they couldn't deliver oxygen content that they needed because of shunting and they had RV noncompliance. So there are other cause of patients who have cyanosis or low oxygen system exaggerations without elevation of pay pressures. And so the other case would be like the Epstein patients who have a S. D. S. With um increased ari pressure for you know they're TRS the tier could be directed ready to defect. That you could have like a tree cusp of prosthesis and ari pressure that was elevated and shot. And then we have patients who might be shunting extra cardiac that I do think about. Maybe not so appropriate for this discussion, but patients who have a classic glenn, they can get pulmonary A. BMS and shunt right to left. This is similar to hipAA to pulmonary syndrome. And then patients who obstruct their spc, they can pop off collaterals from the spc to the pulmonary vein which gives them an obligate right to left shunt. So um let's look at case to another problem of someone failing to thrive or having heart failure um with the right heart problem and low oxygen content delivery. So this is a lady who had a patent doctors arteriosclerosis. Big connection between the pulmonary artery and the aorta that caused pulmonary vascular disease. She does have Pulmonary vascular disease pulmonary hypertension. She was diagnosed at age 19 and that can happen. These PBS can kind of slip through the cracks and they don't show up to the patient maybe gets a little blue or has some issues. And her parents were given a terrible outlook. They were told she would probably only live a few more years. And but then they said in this patriarchal time don't tell her just let her kind of live her life. So she was unaware of the diagnosis and she went ahead and finished college and got married and was doing well. And because she shuns right to left she was increasing her red cell count to deliver oxygen content. But she had been undergoing for lobotomy for 30 years because someone was worried that she was hyper viscous. She had one episode of homeostasis and she'd had some S. V. T. And was treated with verapamil. She came to mayo Rochester for referral for transplant. We had recurrent upper respiratory and laura respiratory tract infections. She was very short of breath. Um And it was improving and when we asked her what was happening she said well I noticed I feel really bad after I get a lobotomy. So I started taking iron on my own and then I feel better and tell somebody full bottom eyes is me again. Sarah hemoglobin was 18.2 hematocrit was 57. M. C. V. Was low at 71.6. So when I present this case often you know most people say well go ahead and list for a transplant. This is terrible. She's 54 with pulmonary hypertension. But really what we should do is stop for bottom Izing her first. Now she might at some point need transplant listing. Um, but we could actually improve her heart failure and her ability to exercise by giving her better oxygen content delivery to the periphery. So she doesn't need to have for bottoming. In fact, that's a bad thing to do. So when you have a cardiac right to left shunt including those patients with Eisenmenger syndrome, which is PVR elevation and shunting through either a doctor VSD or an asd. Your tissues are hypoxic when you start to mix that. So the body is pretty smart. If it has tissue hypoxia, it turns up the thermostat. It tells the kidney, hey, make some more red cells because you're the delivery train for oxygen and I need more oxygen. I don't care what the sad is. I just care how much oxygen you're giving me. So the red cells um the kidney tells the bone marrow hey rub up production and red cell mass increases and the tissue oxygenation improves and this is a perfect feedback loop. We don't mess with it. So for the most part, my patients with Eisenmenger syndrome, I know what their hemoglobin is. It never changes if I don't mess with them or if they're not having blood loss from another source, they'll find their stable state and they'll be good. And so this is a new equilibrium that we should let happen. And what's bad about four bottoming people say, well they could be hyper viscous. It's not good to have a hemoglobin that high. But the truth is this is a little bit different state. And if you have low oxygen carrying capacity with iron deficiency, patients aren't going to feel well. And if the red cells start to get small remember hurting CV. Was 71 these red cells are going to be more fragile as they go through the circulation. They're going to fragment earlier than a normal healthy normal sized red cell. And this fragmented destroyed red cells. That's what increases blood viscosity that increases the risk of stroke. And so in our population here um we published this from the Mayor Rochester data. Um The number one cause of stroke in our eyes and our patients was full bottom me because it was causing low M. C. V. And the treatment is iron therapy. So it's really distinct from what you've heard about. And so this is with her permission. This is now actually almost 15 years ago. So she's still going strong. I have a picture of her dancing at her son's wedding. Um she's not been transplanted but we did put her on some pulmonary Visa dilator therapy which is working well for her. We let her find her equilibrium, which was about 21 for her human globe. And she did overshoot and this can happen when you're starting to give back iron stores. Um But we keep our M. C. V. And her iron stores there to normal and she feels great and she's actually able to canoe here a little bit. So this was a case where we treated heart failure by making sure you have oxygen content delivery to the periphery. So are patients who are cyanotic with congenital heart disease do not need routine lobotomy. Our eyes meet. Our patients actually do quite well without heart lung transplantation if we manage them well, there are a few that need to go to transplant but thankfully not that many. And pulmonary Visa dilator therapy is a helpful adjunct. Um You do perform lobotomy for long bone pain, headache or alter meditation if you know that they're not dehydrated already. Iron deficient. And occasionally people will recommend this pre operatively to um improve human synthesis. I actually don't do that. I think it just gets confusing pre and I think sometimes we overshoot but if you are going to do a full body me make sure you give the patient volume stores back with crystal Lloyd so they don't get dehydrated. Okay so case three of another weird and wonderful form of right heart failure with poor oxygen content delivery. So this is a 40 year old man with trisomy 21. He had a member Nous VSD. And he'd been followed actually quite regularly by pediatric cardiology at Mayo Clinic. And so I had the advantage of a paper chart for those of you that have rotated up there. You know, you can get that little paper chart packet that has every piece of information ever seen about the patient. And so I had all of his data and he had been followed and thought that this was sort of a small the medium VSD that didn't need repair. There was no concern that this child and now young man had pulmonary vascular disease or Eisenmenger syndrome. But he was actually very active, worked full time out of uh kind of a packing factory. And as he stands on his feet, although he's getting more and more locks from the Oedema. And he was having increasing fatigue and not used to love going to work. And now he's having trouble completing the work because he was so tired. And so he's seen by family Mad. And they sent him back to me um They didn't really have any other concerns that they addressed to me. There was no other complaints, recognized rumors. That was pretty good, 95 wasn't completely normal, no evidence on exam that he had. Um High hemoglobin is con junk title. We're not injected. Which I tend to see if the hemoglobin is running really high. Um He did have mildly elevated J. V. P. He had a fairly loud murmur of very loud P. Two. His lungs were clear and he was not clubbed or diagnosed on exam. But this was his echocardiogram. So this is a para sternal view. I want to draw your attention right here there. This is part of the member nous septum but you'll also notice the right heart looks quite large. And we see here that he is shunting across the septum, it looks like a pretty good shantia secondary tr as well. This can get a little confusing in this area. But this is really the money shot to give us some concern. The ventricular septum is flattened In Sicilian diastolic. This is a pressure loaded right ventricle. The right ventricle is dilated and the wall is hypertrophy. So this is an RV that is under pressure. Yeah. So I read this is a large VSD. With significant right heart enlargement and some systolic dysfunction moderate tr. And this is how I estimated the pressure is based on T. R. And P. R. 95/33 is what I thought the P. A pressures were going to be. I thought that LV. Systolic function was preserved. So we went to the Cath lab I thought we should really sort of sort out what's going on. This data was a little concerning when he had been seen at 18 and was doing well. So he did have A VSD. Um not much of a shunt because the pressures are equal between the systemic and pulmonary ventricle. So QP QS. Is almost one. Pay pressures were high, 86/46 as we anticipated. But he was pretty reactive in the pulmonary vascular bed. We gave him 100% oxygen and he started shunting quite a bit from left to right. QP QS was Almost relevant at 1.46-1. And when we gave him nitric oxide, he really increased his shunt. But look at this vascular resistance. Really high numbers numbers we don't want to see now these are indexed to body surface area because we did this in the congenital lab. So you can kind of divide these by two for numbers that you're not indexing. Um still incredibly high. 18.89.9. And the drops to 8.2 with nitric oxide. So is reactive but high vascular resistance. So is this just Eisenmenger syndrome? Do we miss the boat? And I need to treat this right heart failure that he's having, you know, with his fatigue and lower extremity edema. Well, I wasn't sure. I mean none of these things exclude that. This is Eisenmenger but this was sort of a weird presentation. Most patients with the VSD especially with trisomy 21 are going to get pulmonary vascular disease before their fifth birthday. He was 18 of his last visit and he was fine. He wasn't significantly saturated but that doesn't mean anything necessarily. But it just brought my attention that something's going on during the day is not always shunting you know right to left. And his bed was very reactive. So I sent him to police ethnography. Um and he had severe non positional sleep apnea with marked nocturnal hypoglycemia. Bit comps this was corrected with CPAP alone. So this was not needing supplemental oxygen. So I started him on CPAP therapy was it was a very compliant young man and was able to do that. We did start raw video and I brought him back for re evaluation. 30 days later His LV Dimension had increased by 10. That tells me that he's shunting a lot left to right at the ventricular level. The Elvis now volume loaded and his RV pressure was unchanged though. But maybe he's got a higher QP Qs. And PVR s lower and I've got the same pulmonary pressure. So I recap them in. His pulmonary vascular resistance had fallen to about five with this therapy. So we sent him for surgical closure after a lot of discussion and we did have metric oxide support in the O. R. But he did not need that. He did fantastic. And this is him three months post op is honorable. Audio on this but and on CPAP but look at the left ventricle. It looks so much better. The RV does not look pressure loaded here and his RV. Systolic pressure was 36. He had mild right heart enlargement, no residual VSD. And good LV function. So this was really a case where the patient did have A VSD. And that did impact some of his um presentation. But this was not Eisenmenger syndrome. So he had right heart failure from untreated severe sleep apnea, plus A VSD. And we were able to sort of treat this right heart failure. And so I bring this to attention to remind us that our patients are not just one thing they can have A VSD. And something else. And we have other tools to treat them such as looking for sleep apnea and things that impact right ventricular function. Okay, final case in this series, 25 year old woman pulmonary treat VSD. So this is the cousin of tetralogy the extreme and there's no outflow from the ventricle to the P. A. S. But you do have a big VSD. So you've got to get a source of pulmonary blood flow. There's no connection essentially from the heart to the pulmonary vascular bed. So she got a central a order to P A shot to give her some blood flow. And then she went to the more classic Bt shunt. Um So subclavian artery to P. A. Shunt and then a modified just means we used a cortex tube There at age six. So she's nobody's trying to treat the underlying condition. We're just giving her sources of pulmonary blood flow using the systemic circulation. Um She unfortunately nothing since age six and she's presenting with increasing cyanosis and she's in Y. H. A. Class three. She really is pretty limited in what she can do. Well, here's the reason we're giving her no pulmonary blood flow. So she had these shots, but the right was severely stay nautical, the left was completely included, so she's really getting blood flow to her pulmonary bed just through some collateral formation. So that's not a very good way to run the circulation. Her pulmonary arteries were attached to each other, they were confluence. The right and left came together, which is good sometimes in pulmonary atresia VSD. There's these tiny little branch ph they're not connected to each other. They're really hard to find and deal with hers were there, but they were little. She's an adult and her RP was four millimeters and her LPO is six millimeters. Well, they've had no blood flow either. She had a lot of collateral. That's how she was living with blood flow. So this is a patient who's got heart failure because we're not providing any source of pulmonary blood flow that's stable to her. So what can we do about this? Does she need transplant or should we do something else? Well, at Cath, it's hard to look at pulmonary Resistance when there's not good sources of flow. It's really hard to calculate this and sorted out. Her RP was 27/16. I mean, I'm not sure what to make of that, but it's there she had a VSD remember these patients are not blue because there um shunting through the VSD. The shunt is obligated because you have to mix in the ventricle. She's she's blue because you have to mix and she's giving her pulmonary circulation from connections from her aorta. Not surprising systemic RV pressure And then her sat with 75% in the thermal artery. Um This is what our purpose look like. Tiny little things with some obstruction. So we thought about giving our new Shante doing a staged repair where we try to give her some blood flow from the heart to the pa's to let them grow a little bit and maybe consider VSD closure at a later date. If it looked feasible, we could send her to transplant. Um But we decided to go for a stage repair because her vascular bed looked in the lungs looked fairly good. Uh So we thought at least we're gonna give her a better source of pulmonary blood flow. So in March of 2012 we gave our 16 millimeter, pretty small context graph from the RV to the P. A. Now we're giving her pulse a tile flow and we're gonna hope that those PS grow. Um The VSC is open. We didn't do anything to that. And then we tried to rehab three months later her pulmonary bed by doing some stinting in the more distal our P. And L. P. A. She did really, really good and we decided she would tolerate VSD closure. So we did that reconstructed the R. V. D. P. A connection with a more adult sized outflow and did some more stinting into the pulmonary bed. And so this is what her connection looked like after. So she's got a pretty good sized connection from the RV two decent sized P. A. S. And she did really well with this. Um She had a normal RB size, tiny residual VSD no conduct gradient. She was not de saturated, I mean, not surprisingly, the RV. Systolic pressure's a little high and we've got a conduit to go through. Pluses pulmonary arteries are not normal size, but she's doing pretty well. E. F. Was 59%. She was not N. Y. H. A. Class one and that was, This was 2013. Um I was privileged to help her and her husband deliver their first child that she successfully carried to term um in 2016. So this was a really nice treatment of right heart failure by providing a better source of pulmonary blood flow. So even with very complex anatomy, sometimes you can benefit from a staged approach to help the right heart cope and to improve pulmonary blood flow. Okay, just have a few minutes left. Um here um We're going to talk about the Fontane circulation. No cases. Again I just want to be a little more didactic and maybe the later date we can um do some case series if you're interested. But remember that Fontane is not a specific operation but a type of surgically created physiology that we're describing when we use that word. And what we're describing is that we're directing cable blood flow spc and I. V. C. Flow directly to the pulmonary bed. Or not using any type of ventricle to pump the blood. So basically it looks like this were just pouring I. V. C. And Spc flow into a funnel. And it's going to passively come into the pulmonary vascular bed and then go across to I say the left atrium but the pulmonary venus atrium would be the best way to comment on that. So why would we do that? Well sometimes we have anatomy that's not going to allow the patient to have two ventricles to support the circulation. And of course we have to have a ventricle support the systemic circulation. So we'll try to redirect flow for that. It's better than our patients say. Like we just saw an example, she had these systemic to pulmonary shots, which you could do. You could provide a source of pulmonary blood flow without a you're one ventricle support both the systemic circulation in the pulmonary circulation. But then you obligate. We mix in your very blue and so if we could separate it like this, you wouldn't be blue and the ventricle would not have to have the volume load or the support of both circulations. It would now just support the systemic circulation. So this is the classic anatomy that um Fontane described using his operation for. But we use it for many other anatomies. But you can see in this case we really would not have the development of a morphological right ventricle so we can't have a pump to both circulations. There's lots of variations. I'm not going to spend a lot of time but you may hear see me right in a report all these different variations. But the right atrial appendage to P. A. Connection is the one I worry about the most, thankfully. We don't do that too much anymore. But this left this big right atrium in the circuit which can cause clot formation and other concerns. Um the spc to the P. A. Can be connected various ways. And if you hear me say a classic glenn, that means that the PSR not confluence anymore. That the spc usually is just going to the right pulmonary artery and the and the main pulmonary artery goes to the L. P. A. This is what we see most often as a bidirectional glenn, which means that the spC is connected to the R. P. A. But the R. P. A. Is confluence to the left. So that's what this connection looks like here. The are atop a connection. But this is a better connection which will see more often now in our patients, which a nice streamlined flow tube to direct flow from the I. V. C. To the to the P. A. S. And then sometimes we'll have this extra cardiac where we're not even doing, we're bringing completely outside the heart. But you can still make a connection what we call administration to the right atrium in this circumstance. So, um administrative Fontane Zara. Way to give basically pop off float gives you pre load to the ventricle at the expense of a right to left shunt, which will make you cyanotic. So why is that? Why is it always right to left? Well, this is the flow. So flow to the pulmonary bed is systemic venous pressure. CVP minus your pulmonary venous pressure. Left atrial pressure divided by your pulmonary vascular resistance. So I can't have flow across the bed of my systemic venous pressure is not always higher than my left. A trailer pulmonary venous pressure. That's why the shunt is right to left. So um I'm just gonna skip ahead here in the interest of time to talk about some of the things we see in the failing Fontane. So we are going to be paying special attention to enter thoracic pressure when you breathe. That matters to the Fontane circuit and volume changes have a lot of effect on cardiac output. So if you dry someone out and make their CVP low you're going to drop their pulmonary blood flow and they're going to not do as well. So to have a successful Fontane the ideal patients going to have preserved ventricular systolic function and diastolic function. We gotta have everything efficient in the circuit. The PVR has got to be really low. The valves have to work well we don't want to have say mitral regurgitation that would impact left atrial pressure adversely or impact ventricular performance adversely. That's going to hurt our circulation. Um We don't want any obstruction in this venus pathways of the I. V. C. And the spc to the P. A. And it's really good to maintain sinus rhythm. These patients really don't like having um dissing Quran E. And there's a tree in their ventricle. So I like to think when I have a fontana's how am I getting this passive blood flow to move? What are the energy sources when I don't have an RV to pump? Well you do get some energy from your systemic ventricular sisterly, right? You're pushing blood out into the circulation. There's energy developed there and then systemic ventricular diastolic is very important. That's sucking blood out of the pulmonary bed. So there's our two main energy sources that we think about the most often. But the last three are really important to our patients and we don't think about this so much in the two ventricle circulation. Arterial elastin is critical. So if I had really nice elastic arteries in the systemic circulation I eject my blood flow. And I have my uh blood volume. My stroke volume come out into the vascular bed and the aorta, for example expands with that volume and then slowly comes back or retracts. That provides more energy to push blood forward. And if you get stiff arteries and lose that elastin you're losing another source of ability to push blood through the circulation. Negative inner thoracic pressure is critical. So every time you take a breath in as a Fontane you're sucking blood into the pulmonary cavity which is good. Your augmenting flow especially from the I. V. C. Gravity matters. If my head is up I get better flow from my spc into the pulmonary bed and in failing cases that matters. I mean you think God all these things sound so small and so minimal but in the failing circulation these things are critical. Um What about pulmonary vascular resistance? People are a little worried sometimes. Maybe the patient couldn't support a transplant if we did that. Um Most of the time the PBR is quite lower you would be dead in this circulation. But if the patient has administration, we can get your trance pulmonary gradient. That's actually the administration gradient directly. So we can look at that for you and we can look at other things we've talked about why patients are blue already and the complications are significant. Unfortunately, this is not a circulation that gives you 80 years of longevity. And some of the rarer things we see are protein losing a neuropathy. This is devastating to our patients. We don't understand all of the reasons behind this, but one of the reasons is high ibc pressure, which causes you to not eventually not have good protein absorption in the bowel. And this can cause severe problems of Probably about used to say 50% mortality of five years. It's better now, but not great. Um Those patients who have that big right atrium in the connection that flow is slow and they're going to get the rhombus and that's terrible to deal with arrhythmias. Also, those extra cardiac and more streamlined two graphs don't tend to have arrhythmia or thrombosis problems. Sometimes the pulmonary veins actually get obstructed the right atrium gets so big presses on the pulmonary veins coming back to the left atrium. That can be really hard. We don't see that in the Newer Font Tans, but basically what we must deal with and what I send to you guys as my colleagues is the failing Fontane. So the patient who can't maintain cardiac output without a CVP, that's like 25. Um and so most of the time that's because they're diastolic performance is poor, well occasionally come up with other causes, but this is the number one cause and of course the highest problem to deal with because there's no no good treatment and the reasons are multifactorial. But the patients really start out behind the eight ball here with poor maya cardio resembling when they were supporting both circulations before they went to Fontane that hurts the ventricular performance lifelong. And then with time ventricular compliance tends to worsen with abnormal ventricular arterial couple. And we talked about that arterial assistance is relevant. Um Wrasse activation is abnormal in this population and they're probably chronically a little esque emmick in terms of um their blood flow delivery. And this all of this leads to ventricular diastolic dysfunction. Um arterial last it's really, really important. But when we think about reducing after low we're not reliably going to increase cardiac index, unfortunately. And I want to show you Um this is a nice study now, back from 2006. Looking at what happens with a group of Montanes and a group of controls with heart failure. Right heart failure. With two ventricles who were given. W. I mean. And so basically in the Fontane group had a lower cardiac output than the controls. Their cDP was hired to maintain that not surprisingly. And with W. I mean the controls did increase their cardiac index, but the Fontanez really did not. And why was that? Well, the contract our response looks similar. We looked at the ventricle, it looked like it improved. But this lack of pulmonary ventricular energy reduce the pre load reserve. So it didn't help the patient out that much. We know that that's the case normally. But maybe there was this important loss of flow pulse it till it e that helps us release nitric oxide in the pulmonary circulation. So the PVR did not decrease like we wanted it to even with some support from china trips that we think might help that and then the abnormal after load behavior this arterial lasted I think as we're learning more about that is so important and so it's so hard to manage these patients. So this is my last slide here. My tip for heart failure is aggressive. After load reduction may not be our option in a patient with a failing single ventricle because of some of these unique properties. And what we might cause. It's just hypertension, abnormal peripheral perfusion like poor kidney perfusion without really getting the hopeful increase in cardiac index that we wanted with the after load reduction. So I think there's some role for drugs like and trust oh, ace inhibitors all of that. I'm not sure that we can be as aggressive thinking like let's drive this forward to improve cardiac output and then our patients might not respond to I Vienna tropic agents like we want, we need to make sure that they're intravascular volume is optimized, or we tend to dry out our two ventricle patients. Maybe we need to run a little higher um ventricular systemic volumes. And then we really want to try to utilize early on in the process, pulmonary vaso dilator is to try to overcome that poor nitric oxide performance from the lack of pulse it'll flow. So I'm sorry. That went a little long. Um, I wanted to cover a few things and I thank you for your attention.