This echo shows the mitral valve of a 50 year old physician with posterior leaflet prolapse and a moderate jet of insufficiency which is demonstrated by the red color backwards into the atrium.
We are now using hooks to perform a valve analysis. When we put saline in, you see the central leak of water out of the ventricle as the two leaflets do not meet. The forceps are grabbing the posterior leaflet and the hook shows the elongation of the chordae or strings that results in the prolapse.
The first step of a valve repair is to mark the supporting strings or chordae that you are going to preserve. As is obvious here, the segment that prolapses often becomes distended like a sail from pressure. So the goal of the valve reconstruction is to perform literally a plastic surgery operation on the leaflets to remove the excess tissue.
We have now used the blue strings or Prolene to mark the margins of resection and what you see is the indentation between the different scallops or segments of the leaflets. Notice the normal height sometimes can be as short as 5 mm to a centimeter and that the distended leaflet segment is over 2 cm tall.
Now we are performing a partial resection of the distended segment. Part of the judgement of valve reconstruction is not resecting too much tissue because need to use the patient’s own leaflet to reconstruct the normal coapting surface. So in this case, I have elected not to resect the entire leaflet but only half of the prolapsing segment. As you can see, there are now good chords marked by the blue strings from the retained leaflet tissue. In order to shape the posterior leaflet we are going to detach part of it from the supporting structure of the valve which is called the mitral annulus. This will allow us to perform a small resection at its base as you can see, which will allow the overall leaflet height to be adjusted so that it matches the residual segments that were not cut. This is a very important part of tailoring a mitral valve repair to create a normal coaptation surface.
I am now measuring or comparing the 2 leaflets to make sure the residual height will be equal. The height of the segment adjacent to the cut segment is also tall so I am using a knife to divide it from the annulus and will similarly cut a small piece of tissue. Watching the operation demonstrates the numerous times judgement is required in performing these plastic surgical operations on the leaflets. Of course, each valve is different and each valve requires a different thought process and different incisions. Before we reconstruct the leaflet we take advantage of the gap created by the resection to place this series of green and white sutures. These sutures will later be used to perform an annuloplasty. An annuloplasty involves tying a ring around the valve to support its normal shape. After placing the annuloplasty sutures we now use a small thread of Prolene to reattach the leaflet to the annulus. So bites are taken through the edge of the leaflet and then through the frame of the valve reattaching it not only in the correct position but with good chordae now supporting its free margin. All of these steps require great precision because the interventricular pressure is quite high. The pressure on the repair will really point out even minor imperfections so the surgeon takes a great deal of time aligning the leaflet back up so that it will have a normal shape and size.
We are now going to perform a similar maneuver on the adjacent leaflet segment reattaching it to the frame of the valve. As this case shows it is not always a symmetric cut or displacement as we have performed what is called a sliding plasty much more aggressively toward the medial side of the valve in order to come up with a symmetric shape.
The next step of a valve repair is to put the 2 cut edges of the residual leaflet back together. We have employed additional small sutures to reconstruct the leaflet edges. Several sutures are used to reconstitute the valve surface. Now you can see the reconstructed posterior leaflet and the uniformity of height of the residual segments. The leaflet is all now well supported by the residual chords at the margin. We now will place the remainder of the ring sutures in the annulus which is the supporting frame around the valve. We prefer rings that are complete so it requires placement of sutures along the top of the valve. The advantage of such rings is that they have a greater remodeling effect or reshaping effect than a posterior band annuloplasty. In this area of the valve extra care must be taken because the aortic valve is just behind the mitral valve in close proximity. Now the next step is to implant the ring. As you can see, we have sizers that we match to the surface area of the anterior leaflet and that helps us pick a ring that will correspond to the size of the valve.
Now the sutures are used to implant the ring and you can see the final repair now. We fill the ventricle with saline and now the valve is completely competent, holding water in the ventricle under great pressure. In a test we designed at Mount Sinai, we now draw a line on the valve with ink which allows us to then assess the amount of leaflet coapting inside the ventricle. As you can see, now several millimeters of the valve, almost a centimeter in the area we resected is all available for coaptation or sealing. The postoperative echo now shows a normal valve motion with a long line of coaptation and no evidence of mitral regurgitation.