The Severity of Functional Mitral Regurgitation Depends on the Shape of the Mitral Apparatus: A Three-Dimensional Echo Analysis
Keiko Aikawa MD, Florence H. Sheehan MD, Catherine M. Otto MD, Karen Coady RCDS, Gerard Bashein MD, Edward L. Bolson MS

The relationship between structural abnormalities of the mitral apparatus and severity of functional mitral regurgitation (MR) in patients with non-ischemic dilated cardiomyopathy, was examined using quantitative three-dimensional echocardiography. Annular size, the central angle between the anterior and posterior chordae, and dilatation of the anterior and anterolateral left ventricular wall were found to be significantly related to severity of MR. It is concluded that functional MR in non-ischemic dilated cardiomyopathy is related to dilatation of both the annulus and of the anterior and anterolateral left ventricle. The latter results in displacement of the anterior papillary muscle, narrowing of the angle of the anterior chorda to the mitral annulus, and widening of the central angle between the anterior and posterior chordae. Knowledge of mitral geometry may be of assistance in therapeutic planning.