Geometric Differences of the Mitral Valve Tenting Between Anterior and Inferior Myocardial Infarction with Significant Ischemic Mitral Regurgitation: Quantitation by Novel Software System with Transthoracic Real-time Three-dimensional Echocardiography

Abstract

We sought to investigate the 3-dimensional geometric differences of mitral leaflet tenting in ischemic mitral regurgitation, comparing inferior and anterior myocardial infarction (MI). Using real-time 3-dimensional echocardiography, we obtained transthoracic volumetric images for patients with significant ischemic mitral regurgitation (9 inferior and 7 anterior). With our novel software system, 3-dimensional images of the leaflets were reconstructed for quantitation. Mitral leaflet configuration was then represented in contour in which the degree of the tenting could be observed. Calculated percent of tethered leaflet area (>5-mm tenting from the annular level) was compared in inferior and anterior MI. Percent of tethered leaflet area was significantly smaller in inferior than anterior MI, reflecting the localized leaflet tenting in inferior MI (16.7 +/- 18.8% vs 38.9 +/- 9.7%, P = .01). In anterior MI, mitral valve leaflets were widely tethered toward the left ventricle, in contrast with inferior MI showing localized tenting of the leaflet.