David Adams: I just want to add my welcome to everybody. Bob, how many meetings is this? Do you know which one this is? Seventh one! And I must say, this is one of the more fun meetings for those of you who havenít been here. Itís very low key, Randy Martin is here to make everybody laugh and please challenge everybody. This meeting, unlike the other ones, is a lot less formal and since there are no answers in valve disease anyway thatís a good way to run this meeting. I also just wanted to take one second and thank the ACC and the AATS, particularly Amy Doucette. When you have four program directors, thatís like herding cats; itís very difficult to finally get here but every year they do that and I really appreciate being involved.
So my first topic is mitral valve pathoanatomy and my disclosures were shown already but Iíve been involved with Medtronic with the Core Valve trial and Iíve been interested in repair products, both with Medtronic as well as Edwards, but Iím not going to show any of those here.
Hereís my question and so let me get you guys to vote here Ė You can see Iím showing an echo on the top and Iím showing you one of those four is actually the lesion that we saw in the operating room and I want to see if we can figure this one out. So, maybe you want to switch to that so we can see the vote? Because they have the question as well. So what do you guys think? You saw the echo moving; A, B, C or D?
So good, most people voted B. Thatís right.
So letís go back and look at the echo for a second. So you can see that the reason that is because the others Ė A, C and D Ė are all posterior leaflet pathology, right? B is really the only one that has a real potential for anterior leaflet pathology unless you thought the anterior leaflet was hiding behind C, but thatís good. So about 4 out of 5 people got that right. Thatís really important because, of course, of those 4 valves B is by far the most difficult one to fix.
So when we look at mitral valve pathonatomy letís start with normal anatomy. We have 2 leaflets, an anterior and a posterior leaflet. The posterior leaflet is longer and shorter and that keeps the anterior leaflet out of the outflow track. And then we have a coaptation, a rough zone, thatís usually 4 or 5 mm tall and thatís supposed to be posteriorly displaced and thatís why the valve has this nice smile, and then you actually have 6 segments and leaflets if you sort of segment them according to Carpentierís classification of P1, and then P2 is your middle scallop, P3, and then you have an anterior and a posterior commissure. The anterior commissure is near the aortic valve here and the posterior commissure is here, and then the anterior leaflet you just divide the same way or the same nomenclature as a posterior leaflet A1, A2, A3. So thatís important. And then we have three different layers, or three different chordal attachments. We have anterior and secondary, and then basal, particularly in the posterior leaflet, and we have commissural chords. Most of you are familiar with this triad that Carpentier developed many, many years ago, trying to add some clarity to nomenclature around pathonatomy and most of us focus on dysfunction because thatís what drives clinical decision making. So what Iím gonna do is focus more today on lesions and etiology with you.
To start with Ė Dysfunction: Why does a valve leak? There are lots of different reasons why a mitral valve may leak and you can see here Carpentier separates out into Type 1, which means you have normal leaflet motion in the annular plane Ė the leaflets move in the annular plane. The most common causes of dysfunction are annular dilatation or leaflet perforation. Type 2 implies excess leaflet motion. In that case, youíve got the leaflets are moving above the plane in the annulus to the margin of the annuls. In the cardiology literature a lot of that is called flail or partial flail. We tend to like to call prolapse and prolapse would be above the margin. And then 3A implies restriction in systole and diastole. That would be a frozen chord or a frozen papillary muscle typical of rheumatic patients. And type 3b means the restriction is only in systole and thatís always from ventricular remodeling. The valve would open normally, but it wonít close normally because the ventricle is tethering the leaflet. So thatís the dysfunction that I think is becoming pretty common now and the vernacular.
Lesions, I think, are more important. I was happy to see almost everyone got that question right about the echo and the lesion because lesions are becoming increasingly important as we tailor surgical strategy, and frankly, as we tailor referral. What I wanted to do is take you through a lot of different lesions today and sort of show you what these different lesions look like. Here you can see the typical lesion in atrial fibrillation. So atrial fibrillation is the most common cause of Type 1 dysfunction. Here what you can see is you have an increase in the circumference of the posterior part of your annulus. Because the fibro skeleton of the heart doesnít continue here, the aortic valve is here, this part of the valve dilates once you get sort of you have a atrial or ventricular dilation. So the mitral valve gets pulled open and becomes more circular. The predominant lesion here is an increase in the length of your posterior annulus and this is common in all types of valve diseases. Itís an associated lesion in degenerative disease, but itís a very common lesion in atrial fibrillation. Thatís the most common time that you will see that lesion.
Annular calcification is also very common and you should look for it because that has a message, I think, in terms of reparability of valves and who should be trying to do what level of valve, as well as a complexity and time that it may take to do a valve operation. Here you can see this very common finding in degenerative disease where you have these micro fissures. We know that the posterior hinge point migrates onto the left atrial wall often, particularly in Barlow deformity, and thatís a common presentation. Then you can see a valve like this where you have this shelf of calcium all the way along the annulus and this can make anything actually quite dangerous. When you have that valve replacement itís not very easy to do either. You really have to think through whether you are going to try to do a valve repair or valve replacement and often times when you see that you are going to do a valve repair. I am going to show a video this afternoon in the surgical section. You have to think through, and sometimes be creative, because you canít just do regular sort of valve repair or replacement when youíve got calcium like that below the annuls and thatís a very common finding in end stage degenerative disease, particularly in elderly people.
Now, in terms of leaflets and prolapse, thatís very important to distinguish as you saw those first four pictures. I just showed you some random pictures Iíve taken over the last few months just to give you a sense, particularly the cardiologists, of the diversity of pathology Ė Why this field is very different, for instance, than aortic stenosis where the primary lesion is calcified leaflets. Here you have so much variability. So here you see a posterior leaflet and a single thin ruptured chord. And hereís one that has a little chordal rupture, again, very simple P2 lesion and this is, again, a little bit more complicated now. Now you have sort of a taller lesion thatís still relatively benign. Then you have this, now itís sort of more asymmetric the prolapse and the leaflet is a little bit taller, and again, all of these are P2 prolapse. So P2 prolapse is not all the same. And then you have this one which is again, another P2 prolapse, but now you can see the P3 segment is tall and uneven and actually prolapses as well so you have an adjacent chordal elongation. Then here you also have P2 prolapse, only now you have P3 and posterior commissural prolapse so here this entire half of the valve including up to the coaptation zone and the commissure has all lost its chordal support. Then here you have P2 prolapse only now you have basically diffuse prolapse. You have a multi-segmented valve, all chordal elongation, the whole posterior leaflet would prolapse and here again you have P2 prolapse but now you can see the gross distortion of the annulus. So you have in this patient a severe degree of annular dilatation and dysfunction here. So thatís something to keep in mind.
And you can see as you just keep walking through here is another multi-segmented valve now with even more excess tissue and this is just garden variety, every day, each valve is a little bit different, so thatís really important I think for both surgical strategy as well as sort of, I think, making decisions about when to refer patients and we will get into that Iím sure later. Then you have this, sort of, scenario where you have diffuse myxomatous changes now and all the leaflets, a bileaflet prolapse. And then here just for interest, was a case we did recently on a cleft anterior leaflet. Most people havenít seen one; you donít see them very often, but thatís actually what a cleft anterior leaflet looks like and then you have the chordal issue. So thatís all the leaflet pathology.
Then chordal issues again weíve shown it can be simple prolapse, more diffuse chordal elongation. This is a very common lesion where you have the fan chord, so the chordal structure that supports the anterior leaflet, one of the commissures, and the posterior leaflet, all elongated together. That actually creates a bileaflet prolapse in the corner of the valve and thatís not a very complex lesion, actually, to repair when you recognize it. This is a very common lesion in degenerative disease which is an associated leaflet restriction. Often times youíll have prolapse and restriction in the same valve and when you see it you almost always see it here and thatís a P1 segment and part of the anterior papillary muscle which becomes shortened and frozen in this corner of the P1 segment so this is a very important lesion to recognize when you are doing patients that have excess tissue that you may have an opposing restriction like that.
Then hereís a typical patient that has rheumatic disease and you can see in the rheumatic patient you have commissural fusion and calcification and you have the shortening of the chords, these thick, short, calcified chords. And then this is the ischemic patient. So patients that have remodeling of the ventricle tether their leaflet. So thatís the hardest lesion to show because the valve essentially looks normal if you just look at it in an arrested heart, but basically the lesion is tethering and thatís what causes the valve dysfunction. So thatís sort of a broad spectrum of common lesions. There are some more uncommon lesions, but certainly thatís going to cover about 90% of what youíre looking at on echocardiography or what we as surgeons would see in the operating room.
I just want to spend the last couple of minutes talking about etiology. Because etiology is very important because etiology gives you a sense of where you are going with lesions and that will help you, I think, sort out in the future how to take care of patients. So if you look across the spectrum of disease between fibroelastic deficiency ,and then what we call FED plus where you have a little excess tissue or myxomatous change in the prolapsing segment, and then this Forme Fruste of Barlowís, sort of the in between stage between single segment myxomatous change and multi-segment myxomatous change, and then the true Barlow patient that has large valve, multiple areas of excess tissue, and you can really, sort of, go across the spectrum and just talk about tissue. And that has, again, I think implications for both timing, referral, and surgical therapy.
Let me just show you again, by echo, what these different valves look like. So thatís a typical patient that has fibroelastic deficiency. They have a relatively small valve, almost always isolated prolapse from a single ruptured chord, and when we look in the operating room this is what we would see on an echo like that. Almost always there is minimal change in the tissue, you see the thin chord here. And I donít think you have to be a surgeon to know this is a relatively simple valve to repair. So there is a thin chord typical of fibroelastic deficiency and a small ring. So the ring sizes, for cardiologists, go from 24-40 so a 26 would be one of the smallest rings. Itís always a small valve size in fibroelastic deficiency. Now the fibroelastic deficiency plus, the other picture I showed you at the beginning, thatís what that would look like. So you still have a flail segment, or a broken cord, but the pathology, basically, is limited to a single segment. And so if we look at that valve, again you can see that the P2 segment is quite tall, P3 is a normal height, and P1 is actually quite short in this patient. And again itís a small valve. So itís a little bit along that spectrum, still a very straight forward valve with a single lesion.
Then this is the intermediate, probably a Forme Fruste, it really implies itís unclassifiable because it shares characteristics between, sort of, both spectrums. And there you see a bi-leaflet prolapse, lots of excess tissue, and Iíll show you why we call it a Forme Fruste of Barlowís. So hereís that valve, multi-segments, all of the indentations and the leaflets go to the annulus, thatís a free commissural leaflet that happens in about 5% of patients. This is actually a very complex valve to repair because youíve got a small orifice and multiple free segments of leaflets so it is always a repairable heart valve, but look at the size. It is only a size 30, but you have these giant multiple segments of prolapse. So this is one, as surgeons know, we have to pay very careful attention to because this is the patient that really is at risk for systolic anterior motion post-repair. So thatís important to recognize particularly if you are not doing a lot of these. Think about the annular size as you are planning your operative strategy when you first look at the valve. And then this is the last style which is the Barlow valve. This is the common valve in young people that have had sort of 20 year histories of disease and whenever you see this echo, and this is the echo we saw where most of you got it right, thatís a typical, sort of, Barlow valve. And one point Iíll just make to you that to recognize this is you see how the hinge point of the posterior leaflet has migrated off the atrioventricular junction here. Huggins described that back in the 70ís and thatís really cine qua non with Barlowís Ė this little cull de sac in the posterior leaflet. And thatís why you see us sometimes detach that leaflet and put it back into the ventricle. And thatís what that valve looks like.
And in Barlowís disease you always this diffuse, myxomatous change, multiple segments of chordal elongation. And really regardless of your repair strategy, you need to think about multi segment prolapse and also again pay attention to systolic anterior motion. You can see thereís the largest ring on the shelf, a size 40, so thatís the other end of that spectrum. Remember, the pathologist canít tell you because if you just send a piece of prolapsing tissue it will look the same under the microscope. You have to look at the other parts of the valve to figure that out. The history helps you. So remember, FED is typically older patients, shorter histories, and single segment prolapse. Barlowís are younger patients, longer histories, multi-segment prolapse. Thatís the easiest way to sort of think through those. And remember, all the surgeons know this, the etiology in lesions are how we define repair strategy. Personally, I think itís also going to help us in referral in the future, and remember, we are modifying how we do these operations. Thatís how everybody got done 20 years ago. Today, we look at lesions and we make triangular resections, or quadrangular resections, or slide the leaflets, or replace the leaflets, or tie them down. Itís not just one procedure anymore. Thatís why lesions are so important because when we see different types of lesions weíll either do no resection, or minimal resection, or weíll remove tissue out, and thatís why youíll always hear us talk about lesions so much because we started that, sort of, conversation a few years ago and I still stand by it. I think the most important thing in terms of quality in degenerative valve disease is understanding lesions and, sort of, practicing surgery based on the etiology of disease.
Thank you very much.