Restricted diastolic opening of the mitral leaflets in patients with left ventricular dysfunction: evidence for increased valve tethering

Abstract

Patients with LV dysfunction and systolic IMLC also have restricted diastolic leaflet excursion that is independent of inflow volume, coincides with the tethering line connecting the annulus and papillary muscle and reflects limitation of anterior motion relative to the posteriorly placed papillary muscles without a decrease in total orifice area. These observations are consistent with increased tethering by displaced mitral leaflet attachments in the dilated ventricles of patients with IMLC that can restrict both diastolic opening and systolic closure.

Prediction of Long-Term Survival in Patients with End-Stage Heart Failure Secondary to Ischemic Heart Disease: Surgical Correction and Volumetric Analysis

“…Earlier reports demonstrated that functional MR may result from dilation of the mitral annulus, laterally displaced papillary muscles, and enhanced tethering force of the valve leaflets in the hearts with dilated LV. 20,21) Thus, the distance between both papillary muscles was approximated through the left ventriculotomy of the antero-apical LV wall during SAVE and EVCPP procedure. In contrast, the posterior LV wall between both papillary muscles was directly closed and approximated during PRP procedure.…”

A Comparison of 2 Mitral Annuloplasty Rings for Severe Ischemic Mitral Regurgitation: Clinical and Echocardiographic Outcomes

“…2 Restrictive MVA, which was first introduced by Bolling et al 3 in patients with endstage ischemic and nonischemic dilated cardiomyopathy, has become a standard procedure for treating secondary MR. Undersized rings may reduce the leaflet area necessary to cover the orifice, move the leaflets closer, together by reducing the anteroposterior (septolateral) annular diameter, and thus facilitate effective coaptation. [13][14][15][16] Furthermore, restrictive annuloplasty has been associated with a high recurrence rate of MR (10%-30%), partly owing to further distortion of the mitral valve apparatus (ie, increased posterior leaflet tethering) and continuous LV remodeling. 17 The group of Dion et al 15 stressed that sufficient coaptation reserve might prevent recurrent MR, although this therapeutic approach does not directly address tethering by the remodeled LV.…”

Surgical Ventricular Restoration for Ischemic Cardiomyopathy with Functional Mitral Regurgitation

“…Under normal conditions, both mitral leaflets create a deep coaptation zone at endsystole to prevent regurgitant blood flow. However, earlier experimental and clinical studies demonstrated that restricted diastolic opening of the mitral leaflets increased valve tethering, resulting in functional MR in hearts with LV dysfunction 33,34) . The mechanism of functional MR can be understood in terms of an altered force balance on the mitral leaflets in systole; i.e., a combination of increased tethering forces that restrain the leaflets from closing and result from an altered three-dimensional geometry of leaflet attachments associated with LV dilatation and decreased ventricular forces that act to close the mitral leaflets.…”