Assessment of Longitudinal Myocardial Mechanics in Patients with Degenerative Mitral Valve Regurgitation Predicts Postoperative Worsening of Left Ventricular Systolic Function

Abstract

The optimal timing of mitral valve repair (MVr) in patients with chronic severe degenerative mitral regurgitation (MR) remains controversial and is broadly based on either measurable loss of systolic function, as determined by left ventricular (LV) ejection fraction (LVEF) and/or LV chamber remodeling. The aim of this study was to test the hypothesis that the assessment of LV deformation by speckle-tracking echocardiography might uncover subclinical changes for predicting reduction of LVEF after MVr. One hundred thirty patients (mean age, 57 ± 14 years; 85 men) who underwent MVr for chronic severe degenerative MR were retrospectively identified. Baseline and immediate postoperative transthoracic echocardiography was used to assess global longitudinal strain (GLS), global radial strain, and global circumferential strain before and after MVr. In comparison with baseline, MVr resulted in significant reductions in LVEF (P < .0001) and in GLS (P<.0001). Postoperative change in LVEF was related to the changes in GLS (r= -0.71, P < .0001) and global circumferential strain (r= -0.22, P= .01) but not global radial strain. For the entire group, the presence of a high preoperative GLS magnitude predicted a postoperative reduction in LVEF of >10% (odds ratio, 0.80; P < .001). Furthermore, GLS showed diagnostic value in predicting a reduction in LVEF of >10% with a resulting postoperative LVEF of <50% (area under the curve, 0.93; P < .001). In chronic severe degenerative MR, disproportionately higher LV global longitudinal strain signifies a maladaptive preload-related change that is associated with substantial loss of LVEF immediately after MVr. Preoperative assessment of longitudinal strain may be potentially useful for optimizing the timing of MVr for degenerative MR.