Reply to Kiris et al. Free

We appreciated the Letter to the Editor by Kiris et al. [1] and considered several points.

1. Chordopapillary apparatus preservation during mitral valve replacement (MVR) enhances left ventricular (LV) function in patients with mitral regurgitation (MR). Postoperative LV volumes decrease and ejection performance continues to improve over time. In rheumatic patients with mitral stenosis, fibrotic-calcified leaflets and diseased subvalvular apparatus, this preservation may be difficult. Sometimes subvalvular apparatus is widely resected resulting in papillary muscles-mitral annulus discontinuity. In this complex scenario, the aim of preserving techniques is to prevent postoperative LV remodeling and, at least, maintain LV volumes as preoperatively. Our technique may be a good solution for these patients. Conversely, the technique reported by Kuralay et al. [2] was performed in patients with degenerative MR in which mitral valve repair is the best option. In our opinion, this technique cannot be applied to thickened-calcified rheumatic valves.

2. Five hundred and sixty-six rheumatic patients underwent MVR (1996–2006). One hundred and fifty six had complete valve excision (group 1), 248 preservation of posterior leaflet (group 2) and 162 complete chordal preservation (group 3). The patients reported in our article were included in group 3. They were retrospectively compared (data not published). At 1-year follow-up, LV volumes were reduced in groups 2-3 (preoperative end-diastolic volumes: 166 ± 5, 170 ± 1 ml; postoperative: 155 ± 1, 154 ± 3 ml). In group 1, volume increased (168 ± 2 to 175 ± 3 ml) and LVEF declined over time. Persistence of pulmonary hypertension (PSAP > 40 mmHg at 1 year) was higher in group 1: 48.6 vs 32.5 and 23.2% (p < 0.01). Only a trend in improved outcomes was observed in group 3 with respect to group 2 and in ‘posterior transposition’ patients when compared with other patients in group 3.

3. In Feikes technique the anterior leaflet is incised in the midline and two segments are turned backwards. In our technique, the leaflet is incised at its base, completely detached and implanted posteriorly as a large fibrotic-calcified patch (as a protective curtain of posterior atrioventricular groove).

4. ‘Natural position’ is a fictitious term. Secondary chordae attach to the ventricular surface of the leaflet. Their ‘natural position’ is not the anterior annulus, they are moving across the mitral orifice. Moon et al. [3] published a sophisticated study in dogs comparing conventional MVR with anterior and posterior chordal-sparing techniques. Conventional MVR was associated with depression in systolic contractility. Certain parameters suggested that systolic function was better after anterior than after posterior MVR, but the relative changes did not attain statistical significance. Soga et al. [4] described a chordal-sparing technique using ePTFE chordae: one for the anterior papillary muscle is attached at the 9–10 o’clock position on the mitral annulus, and the other for the posterior papillary muscle at 5–6 o’clock. An ‘oblique’ direction enhanced systolic function with better results than anterior, posterior and counter directions [5]. A modification of our technique should be an ‘oblique transposition’: A1 segment reattached at 9 o’clock and A3 at 5–6 o’clock. Anyway, we agree with the comment by Moon and co-workers: ‘…in selecting which type of chordal-sparing technique to use, the choice should also be based on other factors, including the simplicity and reproducibility of the technique…’; an important consideration in rheumatic mitral valve disease.

References