Reply to Kestelli et al.

Abstract

We would like to thank Dr Mert Kestelli et al. [1] for their interest in our study [2] and for the issues they addressed in their letter. We agree with them that the reduction in the septal–lateral dimension of the mitral annulus provided by undersized ring annuloplasty may contribute to the decrease in the left ventricular (LV) volume after surgery. However, this effect alone is not sufficient to explain the occurrence of reverse LV remodelling which is a multifactorial process still rather difficult to predict as demonstrated by the fact that it could not be demonstrated in 43% of the patients in whom this end-point was assessed. As clearly described in Results section of our manuscript, associate procedures such as myocardial revascularization, successful ablation of atrial fibrillation and cardiac resynchronization therapy were not positively related to the occurrence of reverse remodelling. For some of them, such as cardiac resynchronization therapy, this lack of effect could probably be due to the small number of patients treated. The patients with preoperative asymmetric tethering were 18 (24%) and had a significantly higher recurrence rate of mitral regurgitation (MR) compared with those with preoperative symmetric tethering. In our opinion, this represents a very important finding that should be taken into consideration when selecting patients for whom an undersized annuloplasty is evaluated as a possible therapeutic option. According to our results, in the presence of prevalent restricted motion of the posterior leaflet, additional surgical techniques addressing the subvalvular apparatus or mitral replacement rather than repair should be considered. With regard to the recurrence of MR following undersized annuloplasty with a GeoForm ring, 9% of our patients had moderate-to-severe (3+/4+) mitral insufficiency at follow-up (and not 16% of them, a percentage that also includes the cases with 2+/4+ MR). This rate is comparable with that reported with other types of ring [3] and is likely to further decrease if preoperative predictors of repair failure identified so far will be taken into account during the decision-making process. However, we strongly disagree with Kestelli et al. about the use of flexible rings in functional MR since it has been demonstrated in several observational and randomized studies that they are associated with a higher rate of annular re-dilatation and MR recurrence compared with the rigid ones [4, 5], and their use should therefore be discouraged in this setting.