J Thorac Cardiovasc Surg 2007;133:646-647
© 2007 The American Association for Thoracic Surgery
Surgery for Congenital Heart Disease
The illustrations in your presentation look similar to the illustrations of the monocusp with the exception that you sew the edge of your pericardial patch augmentation to the residual cut edges of the leaflet that you cut across. And when your annulus is only 6 mm, and I look at those valves, theyre so dysplastic, sewing a pericardial patch to the edges of the leaflets just seems kind of difficult in a 3-, 4-, or 5-month-old child. So I wonder, the patches that you actually sew into these patients must be much wider than the rest of the cusps put together to get an annulus diameter big enough for that child.
When we originally started using polytetrafluoroethylene (Gore-Tex) monocusps, we sewed them to the pulmonary artery wall rather than the residual leaflet tissue. They were big enough to be draped across the back of the RVOT so that it made it a monocusp. How do your patch dimensions compare with our polytetrafluoroethylene (Gore-Tex) monocusps? We know that our polytetrafluoroethylene (Gore-Tex) monocusps last 2 or 3 years, and I am interested to find out whether these pericardial cusp augmentations will last even a longer period of time. So thats the first question. Is there really a difference between your technique and what weve been doing for 10 or 12 years?
Dr Anagnostopoulos. I think the difference is that by suturing the pericardial tissue into the native valve apparatus, we try to use the hinge mechanism of the valve and make it coapt with the rest of the tissue. That cannot be done in the subset of patients in whom the annulus is less than 4 or 5 mm, and in very dysplastic valves. In these patients, the transannular patch is still our technique of choice.
To answer your question, I think, yes, our cusp is bigger than the monocusp, the way I understand it by looking at your illustrations. The monocusp is a technique that we dont use at UCSF. The pericardium is more pliable and gives you more lead to be able to use a wider patch than the traditional monocusp.
Dr Brown. My second question is that at least in people who have used a biologic monocusp, a cusp from a homograft, autologous pericardium, or bovine pericardium, none of them have remained functional after about 3 or 4 months. Your follow-up is 7.5 months, on average, with a follow-up of more than 2 years. Do you think your monocusps for some reason are going to be more durable than those of everybody else who has tried the biologic monocusp?
Dr Anagnostopoulos. The only reason why this could happen, if it does (and as you said, we dont have the data yet), is because it is attached to the valve tissue itself. The theoretic potential of growth of the remaining native valve tissue exists. I think only time will tell.
Dr Brown. About 25 patients, or 27% of your patients, who had the cusp augmentation had moderate to severe PI. What do those cusps that failed look like? Are they fixed in the open position, as I would expect? Are they still mobile and they just werent sized right? Why do 25% of your patients have moderate to severe PI early after operation?
Dr Anagnostopoulos. They are fixed in the open position as you described. This probably represents technical problems with the construction of this pericardial cusp augmentation flap. It mostly happened in the beginning of our experience. Dr Sung, in his article, quotes a similar problem in 2 of his 18 patients. The rate of deterioration in his study was 17% in 2 years and was 17% in ours as well. So I think that it had to do with the way we did it, and I think we learned better how to do that as time went by. I dont remember, in the last part of our experience, seeing that problem anymore. That was part of our learning curve with the technique.
Dr Brown. I congratulate you and your group for attempting to reconstruct the pulmonary valve in every transannular patch reconstructive. We totally agree. I think time will only tell whether this biologic cusp augmentation is going to have the same fate that others have or whether it will be better.
Dr Y. Kawashima (Minoo City, Japan). I congratulate Dr Anagnostopoulos and his coauthors for their excellent results of transatrialtranspulmonary repair for patients with TOF, particularly in patients who underwent pulmonary valve augmentation. As you may know, I started this transatrialtranspulmonary repair for TOF in 1978, and I have simultaneously repaired the stenotic pulmonary valve precisely using the cusp augmentation technique with an autologous pericardium when necessary with a method similar to that reported today.
Recently I reviewed the late result of the initial 110 patients who underwent operation 16 to 28 years ago at the age of 5 years or less. There was 1 operative death, and 1 patient died 18 years after surgery. Among the other 108 patients, followed on an average of 22 years, 8 patients underwent reoperation, 7 for recurrent infundibular stenosis and 1 for calcified annular patch; however, no patient underwent reoperation for pulmonary regurgitation.
I presume this is because of the somewhat functioning repaired valve and a slightly enlarged pulmonary annulus. Excessive enlargement of the pulmonary annulus was not necessary in our series because of the initially functioning pulmonary valve.
I agree with the authors conclusion that pulmonary valve repair using the cusp augmentation technique reduces the incidence of postoperative pulmonary regurgitation, and my conclusion is that precisely performed cusp augmentation reduces pulmonary regurgitation even on an average of 22 years after surgery.
Dr Anagnostopoulos. Thank you for those comments.
Dr M. Wojtalik (Poznan, Poland). According to the drawing you have presented, it seems that there are 2 large patches reconstructing the RVOT, 1 inside creating the cusp and 1 outside. I would be afraid about the creation of the clotting between and obstructing the RVOT. Did you observe such a complication?
Dr Anagnostopoulos. We followed those patients, and at this median follow-up of 8 months we havent seen any clots. One patient had to undergo reoperation for residual RVOT obstruction, but during the operation it was clear that this was because of the obstructing muscle fibers in the outflow and not because of the cusp obstructing the valve at the valvar level.
Dr S. Bradley (Charleston, SC). What do you and Dr Karl think are the best anatomic selection criteria for using this technique? It sounds like it would be difficult to use with a very small pulmonary valve (a z score of 4 or so) or a stenotic unicusp valve, as opposed to a valve that was mildly stenotic (z scores of 2 to 3). Is that fair, and do you have those criteria?
Dr Anagnostopoulos. Yes, thats fair. The ideal valve for this technique is one that has the commissures at the 3 and 9 oclock positions so the anterior leaflet can be bisected in the midline. Those are anything from 50% to 70% of the valves, according to Dr Kawashimas study from 1981, and according to Steward and colleagues series from last year that was presented at the Society of Thoracic Surgeons meeting. So I think it can be done. When the commissures are aligned at the 6 and 12 oclock positions and you cut through the anterior commissure, there is not a lot of valve to sew and you end up reconstructing the RVOT with what looks more than a monocusp valve. But when you have valves that are oriented at the 3 and 9 oclock positions, then you can really do it because there is a nice remnant to sew your valve augmentation flap on.
Dr A. Schlichter (Buenos Aires, Argentina). I have a short comment and 1 question:
First, it takes a little longer to apply 2 patches than only 1. What we do is prepare our patch with untreated pericardium, adapted to the exact size that the patient needs to have the pulmonary artery and annulus enlarged, according to tables and body surface area. Having measured the patients annulus, a resident produces the monocusp on the patch, and we then suture the patch on the annulus.
Are you taking into consideration the diameter that you need to obtain for the enlarged pulmonary annulus and artery? I am asking this because we are now concerned about long-standing pulmonary valve incompetence, which is in relation to the diameter of the pulmonary artery at the time of its surgical enlargement. If we enlarge it too much, we are probably going to have more PI in the long term and more reoperations for TOF. It has been some time since we changed our policy of wide enlargements, and we now prefer to tailor patches to the patients needs or even a little smaller. In the long term we think it is better to have a nonsignificant pressure gradient than severe pulmonary valve incompetence.
Dr Anagnostopoulos. When we construct that patch, we have in mind what the pulmonary valve annulus should be for that particular patient. To not prolong the operation, you cannot really have it preformed and suture it on because you have to be able to see the valve. Otherwise you can end up creating technical problems; you can tear those valves that sometimes are dysplastic and very thinned out.
To do that, we snare the patent foramen ovale, and then we do this part of the reconstruction on the beating heart. So even though it may take some more time, at least thats not ischemia time.
J. Thorac. Cardiovasc. Surg. 2007 133: 640-647.
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