Influence of procedural differences on mitral valve configuration after surgical repair for functional mitral regurgitation: in which direction should the papillary muscle be relocated?

Abstract

BackgroundAfter restrictive mitral annuloplasty (RMAP) for functional mitral regurgitation (MR), the MR frequently recurs. Papillary muscle relocation (PMR) should reduce the recurrence rate. We assessed the influence of procedural differences in PMR on the postoperative mitral valve configuration.MethodsThirty-nine patients who underwent mitral valve repair for functional MR were enrolled. In limited tethering cases, RMAP alone was performed (RMAP group; n = 23). In severe tethering cases, in addition to RMAP, bilateral papillary muscles were relocated in the direction of the posterior annulus (posterior PMR group; n = 10) or anterior annulus (anterior PMR group; n = 6). We performed pre- and postoperative transthoracic echocardiographic studies, introducing a new index, mitral inflow angle (MIA), to assess the diastolic mitral leaflet excursion. MIA was measured as the angle between the mitral annular plane and the bisector of the anterior and posterior leaflets.ResultsPostoperative MR grade was significantly reduced in each group (P < 0.001). Follow-up echocardiography showed recurrent MR in 13% of the patients in RMAP group. In contrast, no recurrent MR was observed in either the anterior PMR or the posterior PMR group. After surgery, MIA was significantly reduced in both the RMAP group (P < 0.01) and the posterior PMR group (P < 0.001), but was preserved in the anterior PMR group (NS). None of the postoperative variables showed any significant difference between the early and late postoperative phases.ConclusionsIn the surgical treatment of functional MR, a PMR procedure in addition to RMAP was effective in reducing systolic MR. However, mitral valve opening assessed by MIA was restricted even after RMAP alone. The restriction was severely augmented after additional posterior PMR, but was attenuated after additional anterior PMR. The papillary muscle should be relocated in the direction of the anterior annulus to preserve the diastolic opening of the mitral valve.Electronic supplementary materialThe online version of this article (doi:10.1186/s13019-014-0185-6) contains supplementary material, which is available to authorized users.

A Meta-Analysis of Ring Annuloplasty Versus Combined Ring Annuloplasty and Subvalvular Repair for Moderate-to-Severe Functional Mitral Regurgitation

“…The search protocol yielded 392 studies, of which seven satisfied the inclusion criteria and were included in the quantitative analysis (Fig. ) . All of the included studies were retrospective or propensity‐matched analyses, and consisted of 531 total patients.…”

“…In patients undergoing chordal cutting, the secondary order chordae tendineae that originated from the papillary muscle or muscles affected by the infarcted myocardium were divided in two studies, while all of the secondary chords were divided in one study, regardless of the originating papillary muscle . For papillary muscle relocation procedures, the posterior papillary muscle was relocated toward the anterior mitral annulus utilizing polytetrafluoroethylene sutures from the papillary muscle head through the aorto‐mitral continuity in one study, bilateral papillary muscle relocation to the ipsilateral annulus was performed in a second study, and bilateral papillary muscle relocation to either the anterior or posterior annulus was performed in a third study . Finally, for papillary muscle approximation, a 4‐mm polytetrafluoroethylene tube or umbilical tape was used to encircle and approximate the papillary muscles …”

“…1). [9][10][11][12][13][14][15] All of the included studies were retrospective or propensity-matched analyses, and consisted of 531 total patients. Ring alone was performed in 301 patients, while a Ring þ Subvalvular repair was performed in 230.…”

Left Ventricular Reconstruction and Mitral Valve Annuloplasty Combined with Papillary Muscle Relocation for Severe Ischemic Mitral Regurgitation

“…However, MAP combined surgical ventricular restoration cannot always eliminate MR when the LV is remarkably remodeled; thus, an additional subvalvular procedure should be PMR corrects tethering at the subvalvular level, relocating an outwardly and apically displaced PMs toward the mitral annulus [3]. The posterior PM is usually a target for relocation in asymmetrical tethering [3] [4]; however, both PMs are targets in symmetrical tethering [5] [10]. Relocation toward the anterior annulus may allow natural directional repositioning of the PMs [4], effectively reducing the distance between the anterior annulus and the displaced PMs [4] and improving the diastolic anterior mitral leaflet excursion [10].…”

“…The posterior PM is usually a target for relocation in asymmetrical tethering [3] [4]; however, both PMs are targets in symmetrical tethering [5] [10]. Relocation toward the anterior annulus may allow natural directional repositioning of the PMs [4], effectively reducing the distance between the anterior annulus and the displaced PMs [4] and improving the diastolic anterior mitral leaflet excursion [10]. An approach through the aortotomy enables relocation of the PMs without disturbing mitral chordae tendineae, while precisely avoiding aortic regurgitation [4].…”