Page 99 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

diameters of the mitral valve annulus were measured in the anteroposterior direction from the parasternal long-axis view and in the intercommissural direction from the apical 2-chamber view. Mitral valve tethering was assessed measuring the distance between the coaptation point to septum, tenting height (the distance between the coaptation point of the mitral valve leaflets and the mitral valve annular plane) and tenting area (the area enclosed by the mitral valve leaflets and the mitral annular plane). The length of the anterior and posterior mitral valve leaflets were measured in mid-diastole on the parasternal long-axis view. The maximal tethering location was determined according to the scallops of the posterior mitral leaflet. The distance from the posterior papillary muscle to the mitral annulus was measured in the apical 4- and 2-chamber views while the distance from the anterior papillary muscle to the mitral annulus was measured in the apical 2-chamber view. The mitral posterior leaflet angle and the basal and distal anterior leaflet angles were measured on the apical long-axis view.
Statistical analysis
Categorical data are presented as frequencies and were compared by Chi-square test or Fisher’s exact test, as appropriate. Continuous variables are presented as means and standard deviation or median [Q1, Q3] and were compared by Student’s t-test or Wilcoxon Rank Sum test. The independent association between the various clinical and echocardiographic parameters with the occurrence of the endpoint was assessed with univariate and multivariable Cox proportional hazards regression analysis. The relative effect of treatment vs. control arms on the risk of the endpoints associated with clinical and echocardiographic variables was assessed by formal interaction testing. Statistical analyses were performed with SAS version 9.4 (SAS Institute, Cary, NC).
Figure 1. Examples of mitral valve geometry measurements on two-dimensional transthoracic echocardiography.
Panel A shows the parasternal long-axis view, demonstrating the measurements of coaptation to septum distance, tenting height and tenting area (the area enclosed by white lines). Panel B shows the apical 4-chamber view, demonstrating the measurement of posterior papillary muscle
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