Reply to Kestelli et al.

Abstract

We thank Kestelli et al. [1] for their interest in our article [2] and appreciate the editor for the opportunity to reply. To begin with, we would like to stress on the importance of selecting patients who will be best benefited by repair in rheumatic mitral valve disease. Most important factors determining the reparability include the extent of subvalvular apparatus involvement, degree of calcification, and severity of leaflet retraction. If the continuity from papillary muscle to leaflet edge is not pliable enough, coaptation margin will not allow a competent valve function even though sufficient leaflet surface area is obtained through leaflet augmentation procedures. In such cases, valve replacement will be a better option because, as was shown from our previous report, long-term clinical outcomes of mechanical valve replacement were nearly comparable to those of valvuloplasty [2]. We believe ring annuloplasty should be performed even if the valve appears competent following leaflet procedures because the annulus has already been affected by the disease and therefore further annular dilatation is possible. In case of rheumatic mitral regurgitation, the maintenance of both annular dimension and its shape is known to play an important role to prevent mitral regurgitation recurrence [3]. Therefore, implantation of a complete rigid ring (or a semi-rigid ring) is preferred over flexible or partial rings. Generally, the selection of ring size is based on the measurement of anterior leaflet surface area. With adequate process of patient selection, ring annuloplasty can offer a sufficient coaptation margin even without leaflet extension or augmentation in many cases. For this, the restrictive motion of leaflet (type IIIa dysfunction) should be relieved by adequate release procedures such as commissurotomy, papillary muscle splitting, and leaflet mobilization according to the morphology of rheumatic involvement. In cases where leaflet edges are as pliable as to allow repair but leaflet surface area is insufficient to make adequate coaptation margin even after release procedures, leaflet augmentation or extension procedures are necessary to obtain a satisfactory coaptation surface. In these cases, a similar rule is applied in determining the ring size as for those cases without leaflet extension or augmentation. For example, when posterior leaflet is augmented, the adequate ring size is generally the same size as the size that covers the anterior leaflet surface area. When the anterior leaflet is augmented, the ring size should be the same size as the size that covers the entire anterior leaflet including the augmented area. If the sizing is equivocal, we believe choosing the larger size is advisable to prevent mitral stenosis. In our previous report, leaflet augmentation technique was not as frequently performed as in other reports [2]. This is perhaps because we had more cautious and conservative attitudes toward valve repair for patients with more severe leaflet pathology in that valve replacement was preferred in potential candidates for leaflet augmentation. Most importantly, intraoperative trans-esophageal echocardiography should be followed after pump weaning for confirmation of valve competence with adequate coaptation margin. If not satisfactory, re-repair or conversion to replacement should be followed.