The aim – to estimate the role of geometric parameters of mitral valve deformation and remodeling of the left ventricle (LV) in the formation of mitral insufficiency in patients with systolic dysfunction after myocardial infarction (MI) of different localization.
Material and methods. We assessed 99 patients with left ventricular (LV) systolic dysfiunction after MI with mild to severe mitral insufficiency. We evaluated mitral insufficiency by means of echocardiography through determining EROA (effective regurgitant orifice area), assessed indexes of LV global and local remodeling. mitral insufficiency was moderate and severe in 36 patients with anterior MI (group 1) and in 43 patients with inferior/posterior MI (group 2), the control group consisted of 21 healthy individuals.
Results. In both groups of patients rates of global and local LV remodeling were significantly higher than in the control group (P<0.0001). Sphericity index was significantly higher in group 1, compared to group 2 (P=0.003). The indexes of local remodeling were significantly higher in group 1, especially anterior papillary muscle (PM) tethering distance (Р=0.03), posterior displacement of the anterior PM (Р=0.03), PM height (Р=0.01), interpapillary distance (Р=0.02). Correlation between EROA and sphericity index in group 1 was revealed (Kendall τ 0.46, P<0.0001), in group 2 this correlation was weak (Kendall τ 0.23, Р=0.016). In group 1 correlation of EROA with anterior and posterior PM tethering distance was revealed (Kendall τ 0.41 and 0.52, P<0.0001). In group 2 EROA correlation with posterior PM tethering distance and anteroposterior mitral valve diameter was revealed (Kendall τ 0.36 and 0.48, P<0,0001). Correlation between EROA and inferior apical segment akinesia and WMSI of posterior PM was revealed in group 1 (Kendall τ 0.71 and 0.51, P<0.0001), and relation between mitral insufficiency and obstructive lesion in circumflexus (Cx) and right coronary artery (RCA) (Р=0.0008 та Р=0.002) in this group. Conclusions. LV spherisation and PM dislocation are more pronounced in ischemic CMP after anterior MI, compared to inferoposterior MI. Apical and posterior PM displacement, akinesia of inferior apical segment, Cx and RCA obstruction are major determinants of ischemic mitral insufficiency after anterior MI, while posterior PM tethering and anteroposterior mitral annular dilatation are determinants of mitral insufficiency after inferoposterior MI. The obtained data might determine surgical approaches in ischemic mitral insufficiency of different mechanisms.