Annuloplasty for narrowing of the aortic annulus

Dear Editor,

We read with great interest the contribution by Jasinski [1] regarding the ongoing debate on annuloplasty in aortic valve repair (AVR).

There are 2 main ways to improve cusp coaptation and to abolish aortic insufficiency: restoring the size of the cusps by enlarging with a pericardium or narrowing the root (including the annulus) by bringing the cusps closer together [2]. Most cases of aortic insufficiency are attributed to the different heights of cusp free margin (CFM) between particular cusps. It can be caused by a prolapse or, more frequently, a pseudo-prolapse owing to cusp restriction. To elevate the CFM, its shortening (plication, reinforcement) is necessary, which, in turn, decreases the distance between the central point of CFM and the aortic wall at the level of the commissural tops and, consequently, increases the cusp restriction by this ‘iatrogenic’ component. If there is not enough viable cusp tissue (which is always the case in pseudo-prolapse caused by restriction), a meaningful narrowing of the annulus is necessary to achieve a sufficient surface of coaptation between the restricted cusps. Furthermore, because after any narrowing, there is a strong tendency leading the annulus to return to its previous size [3], we agree with Jasinski [1] and other proponents of the annuloplasty that this technique, if used, should be effective and durable, which can be achieved by external support.

Yet, an effective narrowing of the annulus can result in a meaningful decrease of the orifice area and hinder an implantation of a sufficiently large valve prosthesis, should it become necessary in the future. Unfortunately, there are no thorough data in the literature regarding the size of the prostheses implanted after previous annuloplasty, nor the haemodynamic status of those patients. Consequently, in patients with an insufficient amount of viable cusp tissue, a restoration of its size by cusp enlargement with a pericardium should be taken into consideration.

Although here are some reports demonstrating unfavourable durability after AVRs with pericardium, it is not clear if it is really the pericardium itself or the extent of cusp pathology that impacts the outcome over time. It seems apparent that in AVRs without patches, the extent of valve pathologies was less significant than in those in which pericardium had to be used. Moreover, it could be demonstrated that the reason for repair failure was the progression of the pathological cusp changes rather than any degeneration of the patch [4, 5]. Because randomized studies do not exist, it remains disputatious which method is more functional, physiological and durable: leaving the partially pathological cusps within a narrowed annulus/root or leaving the non-narrowed annulus/root with pericardium-restored cusps?

Nonetheless, in all AVRs who needed a valve replacement after cusp repair without any annulus narrowing, the largest valve prostheses could be implanted [5, 6]. An aspect that every surgeon should consider when performing an AVR, especially because the AVR candidates are mostly young, active individuals with a body surface area larger than average.

Conflict of interest: none declared.

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