Dr W. Randolph Chitwood (Greenville, NC). I congratulate Drs Maisano and Alfieri's group for their continuing critical anal-ysis of their patients who have undergone edge-to-edge mitral valve repair. I thank them for allowing me to review their excellent manuscript in advance.
Their earlier studies have shown good results in patients with both single and bileaflet prolapse in which the edge-to-edge method was combined with an annuloplasty ring. Generally, the group has used a complete remodeling ring to support the repair and remodel the annulus. Kunzelman and others have shown that remodeling annuloplasties provide both lower stress along the posterior annulus and better coaptation of the leaflets below the annular plane. More leaflet coaptation eventuates in lower stress on leaflet edges.
In this excellent article Dr Maisano describes 81 patients in whom the annuloplasty ring was omitted with an edge-to-edge repair for a variety of reasons. Of these patients, 60 had leaflet prolapse, 6 had normal leaflet motion but with annular dilatation and a central leak, and the remaining 15 had restrictive leaflet motion. In 32 patients severe annular calcification prevented an-nuloplasty ring implantation. Double-orifice repairs were done in 85%, and in the remaining 15% paracommissural approximations were done. The survival rate was 85% at 4 years, which is lower than that of other series with lone mitral disease. It is most important to note that 9 patients required reoperation.
Patients had significantly higher failure rates when the annulus was even partially calcified and not just with bar calcium. Inter-estingly, these patients had only trivial leaks, as determined by means of the immediate postoperative transesophageal study. Without calcification, double-orifice repairs had a 95% success rate at 4 years, and no paracommissural repairs required reopera-tion. The patients who had progressive leakage could usually be predicted by means of the intraoperative saline test.
In summary, it seems that calcification remains a contraindication to edge-to-edge repairs because of early failure. Our group has followed a similar rationale as Dr Alfieri; that is, if the annulus is severely calcified, then it cannot dilate more and become even more deformed. However, this study suggests that the annulus is already deformed, and it still calcifies in a manner in which abnormal stresses are still transferred to chords and leaflets. In the past, our indications for using this method without a ring have included elderly patients with a completely calcified annulus and for paracommissural bailout operations. We have always pre-ferred to include a band or remodeling annuloplasty ring when possible. In some elderly patients with regional calcium, we have combined the edge-to-edge method with a segmental annuloplasty, deploying segments of a Dacron annuloplasty band in any soft interposing segments between the areas of calcification.
We have not seen an increase in failures in these patients using the Alfieri technique but have seen even more failures in patients with bar calcium and no band. We have had the same experience. On the basis of Dr Maisano's study, the latter appears to be a contraindication, especially with bar calcium, when an annuloplasty band cannot be deployed.
I have 3 questions. What do you think the mechanism of failure is for the repairs that do not have annuloplasty support? Is it ruptured chords, commissural expansion, or another problem?
Would polytetrafluoroethylene chords work here? One would think that nearly pure calcium cannot remodel spontaneously. On the basis of these data, as you begin to develop percutaneous edge-to-edge catheter-repair methods, will you always try to add percutaneous interventions or percutaneous-based annuloplasty? What are you now doing with these patients who are at high risk for failure? Are you doing Carpentier types of annular debridement with reconstruction followed by leaflet repair and a remodeling annuloplasty? This is really the standard in taking care of calcium, as well as a repair at the same time.
I would like to congratulate Drs Maisano and Alfieri for their pioneering work and thank the Association for the opportunity of discussing this article.
Dr Maisano. Thank you, Dr Chitwood. I do agree with your remarks. To answer your first question, the problem of annular calcification is that the annulus is diseased. Therefore it is probably impossible to obtain good results without manipulating it. Therefore in the case of complete calcification of the annulus, probably the best solution, at least in our experience, will be to replace the valve. I do not think that chordal replacement could be a good option in these situations for the same reason why the edge-to-edge repair failed in these patients because the mechanism of failure in these patients has been excess stress applied on leaflets on an already dilated and deformed annulus.
Regarding the second question on the percutaneous approach, I think we are in a very early stage of this new application for the edge-to-edge repair, and I do not know the answer yet. I think that the idea of avoiding the annuloplasty could be a viable solution when the annular function is preserved. In the last few years, our experience with mitral repair has improved, and we are recently looking more carefully at annular function. Therefore, although I believe that you should use a ring whenever possible for open heart procedures, my vision on the percutaneous approach without annuloplasty is that there is probably a subset of patients in whom annuloplasty can be avoided.
The third question is what to do about these patients in the near future. I believe that decalcification is to be done in younger patients, when the risk of the operation is reasonable. Probably the best solution for these patients with segmental calcification of the annulus is decalcification, whereas when the annulus is completely calcified or the patient is very old, valve replacement remains a reasonable choice.
Dr Christophe Acar (Paris, France). Dr Maisano, I enjoyed your presentation very much. Although we have used the Carpentier technique over the past years and we did not find it necessary to adopt the Alfieri technique, I wish to ask you a few questions. First of all, you mentioned that in some patients you now decide to use a prosthetic ring based on the annulus diameter. Could you let us know what sizing criteria you would estimate as being an indication for a prosthetic ring?
It seems that the Alfieri technique can be used to treat both Carpentier type II and III insufficiencies. Your series included various causes, such as degenerative, rheumatic, and ischemic disease. How does the edge-to-edge technique apply both to prolapse and restriction?
Finally, among the various mechanisms of failure, could you tell us again what was the incidence of suture dehiscence?
Dr Maisano. Thank you for your comments. The first question, if I understood well, is when we consider a ring annuloplasty to be necessary. Well, again, my answer is simple. I really believe that in open heart procedures an annuloplasty device has to be implanted whenever possible. Therefore at the moment I cannot tell you a cutoff value. But I really believe that in the near future we have to focus on annular function, evaluating not only the size but also the motion of the annulus to understand whether it is malfunctioning or normal and direct our decision making.
Regarding the second question, we have had quite a bit of experience in using the Alfieri technique both for prolapse lesions and for restricted motion lesions. The technique is effective in both situations.
To answer your third question about dehiscence, we never saw one patient with edge-to-edge disruption in this series. The most common reason for reoperation was annular redilatation and, more rarely, other causes, such as new prolapse lesions in segments that were not treated at the first operation.
Dr David H. Adams (New York, NY). I just wanted to start by giving you a historical perspective. My partner, Farzan Filsoufi, handed me an article a while ago that reminded me that Henry Nichols actually presented edge-to-edge repair at the 36th Annual Meeting of The American Association for Thoracic Surgery in 1956, and it was interesting. His quote was, “Leaflets are not strong enough to hold sutures under tension.” He also had a few other comments. We have seen, in our limited experience with the Alfieri technique, suture breakthrough in rheumatic patients. You did not see that? Leaflets were not tearing?
Dr Maisano. No.
Dr Adams. My second question is about combined type II and type III lesions. In your abstract you note that you had patients who had type III lesions in combination with type II lesions. Is that correct?
Dr Maisano. We had a few patients with a combination of both mechanisms.
Dr Adams. That is an unusual lesion set to have type III lesions in combination with type II lesions.
Dr Maisano. It is not that unusual in rheumatic patients.
Dr Adams. The third question has to do with this risk stenosis. I think it is Dr Acar's question about whether you think there is a risk of stenosis with an annuloplasty versus the edge-to-edge technique.
Dr Maisano. No, I do not think so. The annuloplasty is not a risk factor for stenosis after the edge-to-edge technique. The prob-lem of stenosis comes at the edge of the leaflets. Therefore when the orifice area at the site of the edge of the leaflets is more than 2.5 cm2, for a medium-sized person, you will not have problems of stenosis.
Dr Adams. I agree. My comment would be that I do not think you can create significant stenosis with an annuloplasty ring when the leaflet motion is not restricted.
My next question is about your degenerative freedom from reoperation at 76%, as well as the numbers you gave us that 17 of 81 patients have 3 to 4+ MR. Only 9 have undergone reoperation, but it sounds like 8 more have 3 to 4+ residual MR. Therefore the whole group failure rate sounds like 25%, but specifically in the abstract in your degenerative freedom from reoperation it was 76% at 5 years. What is your comment for that?
Dr Maisano. A confirmation that these results are really sub-optimal, but they are affected by the results in the subgroup of patients with calcification. I do not think that the degenerative disease was the problem. The problem was that we applied this technique in patients with annular calcification (even in those patients with segmental calcification) because we thought it could be a good solution. Actually, that was wrong, and that is why we now advocate another solution, not this one.
Dr Adams. My last comment is about your last sentence: “Although our experience is still limited, the edge-to-edge without ring annuloplasty is a viable option to treat ischemic [mitral regurgitation] in selected patients.” I just would appreciate that in the context of the article presented by the Cleveland Clinic group at the Society of Thoracic Surgeons with a predicted 3-year 3 to 4+ recurrent MR rate actually with a flexible band ring and an Alfieri procedure in terms of the juxtaposition of your observation versus theirs.
Dr Maisano. Well, I did not want to present this message on the basis of a limited number of patients because in this study group we had only 10 patients with ischemic disease. Therefore, on the basis of these data, I would not suggest any message on ischemic disease. Nevertheless, in our experience with an echo-cardiography-based approach, we were very much satisfied by the use of the edge-to-edge repair in ischemic patients, especially when associated with an annuloplasty.
But we are currently running a study adopting the edge-to-edge procedure alone to fix moderate MR in ischemic patients.
Dr Robert A. Dion (Leiden, The Netherlands). Dr Maisano, congratulations for your nice presentation. I just have a technical remark. You told us that the use of the Alfieri technique is not appropriate in the presence of a massively calcified annulus, and you then recommend replacing the mitral valve. Well, in my experience replacing the valve in this situation is as difficult as anything, precisely because of the calcifications. We were also disappointed to experience that the Alfieri technique was indeed not suitable for massive calcification because, of course, an old patient with leaflet prolapse and massive annulus calcification would have been an ideal candidate. The first 3 patients had early failures. In the last 2 patients we first augmented largely the posterior leaflet with a pericardial inlay patch. In 1 patient we then used the Alfieri technique, and in the other one we placed neo-chordae (polytetrafluoroethylene). According to me, this is probably less dangerous than replacement. What do you think about that?
Dr Maisano. I agree with your suggestion, and I think that it is a good idea. The problem with severe annular calcification is that the annulus is already dilated. Therefore, when you use any kind of procedure acting solely on the leaflets, like the edge-to-edge procedure or chordal repair, you leave the annulus dilated. Therefore one good solution could be that of augmenting the leaflets to reestablish a normal ratio between the annular size and the quantity of tissue available for coaptation.
Probably I would use an anterior leaflet expansion more than a posterior leaflet expansion because the anterior leaflet is more suitable for such a technique in the presence of a calcified annulus.