What you are seeing if you have gone to any of these meetings in the last few years, the description of mitral valve pathology you just saw this morning is totally different than three or four years ago. The sophistication of imaging really is catching up, I think, with what we have already seen in surgery. Pravin talked about dysfunction. We focus on dysfunction. Most of the time we say turn the color off, I mean, I think it’s the specialty of the cardiologist and cardiac surgeons; they have been so focused on the regurgitation and the degree of regurgitation and the guideline trigger of valve regurgitation that we are just starting to think more about lesions, and what I want to do from a surgical standpoint is switch gears now and not talk about dysfunctions and take you through some of the history behind etiology and lesions, particularly its relation to degenerative disease. When you look at a mitral valve from the surgical perspective or from an anatomy perspective there are really five structures that you constantly have to think about, and this is relevant in echocardiography as well and for you cardiologists. During some of our case presentations, I am sure you are going to see how these distinct zones can change or it may change your perception of a specific patient. So again, you have two leaflets, an anterior and posterior leaflet. We talk about that, the annulus is the frame around the valve and what you can see is the annulus is shaped like a kidney bean or a “D.” It is not a circle and the fibrous skeleton of the heart and first aortic valve is here, and we see that beautifully on these 3D images. This part of the posterior annular portion is not really covered by the fibrous skeleton of the heart and that’s why the circumference of this area increases as you dilate your atrium and ventricle.
The commissures are an area I don’t think we’ve paid enough attention to and we need to talk more about them. This is the leaflet tissue and it is a defined amount of leaflet tissue and they’re very important; 10% of the time they can be a separate leaflet. If you have a commissural prolapse, it will give you a unique picture on imaging and also in terms of rheumatic disease it is always important if we attempt a rheumatic repair to reconstruct and respect the commissural area. So it is a very common area I think for valve repair failure if you’re not familiar with the specific anatomy there, and then we also, obviously everyone knows about the chordae and how those relate to where the leaflet actually sits and the importance of ventricular dysfunction, not only in ischemic disease if we were to talk about it as the primary lesion, but also in degenerative disease with large dilated ventricles, you have to be careful about opposing dysfunction. So, these are the areas that we talk about and go back and look at the history. This was the first paper to talk about mitral valve regurgitation. It was from John Barlow and it wasn’t diagnosed on echocardiography; it was diagnosed on ventriculography, and he saw the mural protrusion of the mural leaflet into the left atrium and this was really the beginning of the field; we’re talking about the anatomy of mitral valve regurgitation.
It is interesting, if you look in the literature, you will see that for almost a decade every patient that had presumed mitral valve regurgitation was assumed to have Barlow’s valve disease. This is what Barlow’s disease looks like in the operating room and what you can see are giant valves, a lot of excess tissue. You see single segments; sometimes they can cover the entire orifice of the valve. This valve was called the floppy valve in the surgical literature, we prefer the more classic term, Barlow’s disease, and the other thing that you can see and what makes this degenerative process unique is the calcification and restriction that occurs in the setting of prolapse, and you see in this case a typical finding of anterior papillary muscle calcification and retraction opening up this cleft and this annular calcification, which can present like this with the early stage of fissures and thrombin in the later stage of horseshoe calcification, so a very unique disease. Now, in contrast, this was almost a decade later when Carpentier came to the American Heart Association and presented this abstract and what he was describing was a new disease, and he said it was opposed to Barlow’s disease they were seeing then and translucent leaflets instead of excess chordae in thickening they were seeing single chord rupture. So a distinct entity, and it is very distinct and here is what it looks like in the operating room. You can see in this case the distended segment can be enlarged, so prolapsing segments may get thickened but the rest of the valve is normal and you can see and here is a more typical case and if its real what I will consider Carpentier’s disease, a single ruptured chord, very thin, normal-sized leaflets, no distention, no thickening. So a very different disease and this has very important implications not only for cardiac surgeons but for cardiologists. This was another landmark paper from the Bursae Group, published in 1999, where they looked at some of the differences in Barlow’s and FED which hold true today and the first thing you see is the Barlow’s disease is a disease of both leaflets. So keep that in mind when you see patients that you think have bi-leaflet prolapse; most of them are known to have Barlow’s disease. Fibroelastic deficiency is essentially a disease of the posterior leaflet and usually a single scallop of the posterior leaflet.
The other thing that you saw in this early series of differentiation, which holds true today now in larger series, is the age of the patient. Barlow’s patients are the young patients. The patients you guys see that are 45 or 50 and were told they had a murmur when they were 20 or 25, that’s Barlow’s disease. Almost before you put the echocardiogram on, you know that’s what they’re going to have. Fibroelastic deficiency is a disease of older people. Think about the Mayo Clinic paper that Maurice published talking about early referral in asymptomatic patients; the mean age in that series was 64. Mayo Clinic defined severe mitral valve regurgitation in all their early papers that are in the guidelines as flail leaflet. So, these patients don’t typically have chordal elongation; they have single chord rupture, severe mitral regurgitation, and they are typically older and for the surgeons here you can see the difference in the ring size with much larger valves in patients that have Barlow’s disease versus fibroelastic deficiency.
You can’t make the diagnosis if you get a pathology report and the reason is because the pathologist who is receiving this piece of tissue from a patient with fibroelastic deficiency or one from Barlow’s disease. The specific prolapsing segment will share similar features. You may see new polysaccharide accumulation and distention, but you can’t make the diagnosis in a pathology lab. You need to make the diagnosis on echocardiography or in the operating room and we’ve seen today beautifully how we can do this from both Pravin and Roberto with 2D and now 3D echo, which I think is going to represent a major advancement of significant difference between this sort of appearance in this one and this is a very important thing that we start seeing on echo reports. It is very rare. I can tell you one in a hundred that actually come with either of these words typed in a conclusion, and I predict in five years it will be rare to get an echo report where one of these words is not included in the conclusion, and that is going to move this field dramatically forward.
The other little clue that we didn’t talk about this morning or I didn’t hear a lot of talk about, I will just remind you of another classic paper from Hutchins where he was one of the first people to note the displacement of the posterior leaflet on echocardiography in Barlow’s disease. You have this mural progression of the leaflet on to the left atrium and so you will see this space both histologically and more commonly on echocardiography and when I see this displacement that also puts you toward the Barlow category and it is very uncommon to see this except in very large prolapsing segments in fibroelastic deficiency. Here is the spectrum drawn out for you of what we’re looking at is surgery and I think it is Roberto what we are going to start to talk about in the echo lab. I don’t want to get caught up. This phrase is used very common. It’s a myxomatous valve. I don’t really actually like that phrase, it is pathologic description, I am not sure it helps patients very much. It is true that some patients that have FED will have myxomatous changes. I have shown you the prolapsing segment and as the valve gets larger and the patient gets younger, typically you are coming into more in this category of patients. I think for both surgeons and cardiologists we should start talking more about tissue and less about pathologic finding under the microscope and what you can see here clearly is the spectrum can really be taken out based on tissue and volume, and again I think Roberto’s work is starting to show us how; this is I think the beginning of a real scale that is going to help us preoperatively predict the difficulty of valve repair, and I bet you will see that coming up in literature in the next year or two.
At any rate, this is how we would like to present this to surgeons as well as the cardiologists and one other things I will tell you is citing one of the most important lessons I’ve learned from many years of working with Carpentier is the importance of tissue in defining new surgical strategy. So for the surgeons here, we will have a breakout this afternoon and we will talk a lot more about this. It really makes a big difference. Let me just take you quickly through five common cases that you will see. This is a patient with atrial fibrillation and pure annular dilatation. You can see this centrally; you also notice it is not very impressive when you do transesophageal echo in the operating room when the patients are asleep, this lesion will disappear. It is a lesion of minimal coaptation. Here is the valve, and you see the circular shape. Clear demonstration of annular dilatation. It’s not a ’D’ shape. It really is shaped more oblong like a circle. There are no other lesions; here this is a very simple repair, and you can see how the ring is sized to the anterior leaflet. So, that is a case of annular dilatation, by far the most common lesion in isolated atrial fibrillation patients. So, here is a case of fibroelastic deficiency that we have been talking about this morning. You can see a single segment prolapse of P3 from a single ruptured chord. Again, this is a thin leaflet. It is a mistake to start resecting this tissue; you will actually create a restricted lesion, and here is a case for it. You want to think about no resection and in this case we will do chordal transfer and you can also use artificial chordae. There are lots of different ways you can do that, but the point is to recognize this and realize that it’s going to be a small part of the valve you are working on and usually you want to preserve tissue. We will talk some more later in the day about how you can match and that might be a simpler repair than what is coming as we move down the spectrum.
Now here is the next case, another case I’d call FED with a more distended segment. Remember if you are just in the view where you are only looking at P2 you may not be sure whether it is Barlow’s or FED. You have to look at the entire valve. Here is this case in the operating room and now you have a more distended prolapsing segment, but the other portion of the valve is normal and as you will see here is a 4-cm P2 segment and an almost 1-cm P1 segment. That is why I said scan the entire valve and really document the surface area of other leaflets to make the distinction. And this is a case, again there are lots of ways to treat these; I do not like to get caught up in a specific technique anymore than we should talk more about lesions in this case. We will do a resection of this very tall segment and put it all back together, but here’s a case of FED treated by resection as opposed to leaflet preservation. You can see here we are plicating the annulus and sewing the leaflet back together, all geared toward creating this symmetric closure line where when we drop ink on the valve you can see it does actually measure what we will later see in the operating room which is the depth of cooptation. Here is what we call a forme fruste of Barlow’s; some patients don’t have true Barlow’s, they have a giant. You can see this where you would call that Barlow’s; if you look at the anterior leaflet, it’s a giant prolapsing anterior leaflet, normal posterior leaflet if you’ll see.
So here’s a case where the spectrum gets a little bit grayer. I am not sure that matters at this point if you want to draw the line in terms of complexity, it’s probably here, but a normal leaflet here and an abnormal anterior leaflet with prolapse, these patients can be treated usually by just resuspension and occasionally if you have a size mismatch with a sizer will do with limited resection, but the point is that typical patients that are in this grey zone have some normal segments and some abnormal segments. And then the last case I’ll show is a typical case of Barlow’s disease; you can see the similarity of the echo as you were seeing this morning. Of course, this is the patient who has both, all leaflet segments are involved and you see the amount of excess tissue, giant annulus, the largest ring size is a 40, and you can see this patient’s valve is actually in the range of really being larger than the largest manufactured ring size. So, this patient, and again just to show you the complexity, is going to need work on multiple segments, and this is, you know, a three-hour operation. This is not one segment of a surgery; this is a very complicated operation where you detach the valve, shorten leaflets, put it all back together, and you need to deal with the dysfunction of prolapse in multiple different segments. Again, the specific techniques are not so important for the cardiologist; it is here just to understand why this is so much more difficult and how could you possibly expect that valve and a simple case of P2 prolapse to be repaired the same way and that is why I said to differentiate this, this is very important in terms of these echo reports. Now you can see we’re resuspending the anterior leaflet and then the final results, so that’s the way that we will differentiate degenerative disease.
The very last thing I’ll show you is this patient here, because the only other thing you’ll see a lot of is ischemic disease and we don’t have a specific talk about it. Here is a typical patient with ischemic mitral regurgitation. The ventricle is dilated, the predominant lesion is leaflet restriction, so no prolapse and leaflet restriction. You can see the location of the jet on 3D and this is what these valves look like. This is about 30% of the valves in most patients in most cardiologists’ practice because ischemic heart disease is so common. So, this is the valve lesion that you are referring when you have a heart attack or you have a LV remodeling and you have mitral valve regurgitation. You have restriction of the leaflets, you can see the chords are tethered down into the ventricle typically from posterior leaflet displacement, almost always the circular annulus, although usually last thing you’ll see in degenerative patients and then a repair with one of these rings that actually downsizes the annulus to make up for the leaflet tethering. So, that’s a quick tour of what we typically see in the operating room.
Thank you for your attention.
Español
(Video length: 15:26)
