Quantitative analysis of mitral annulus morphology in aortic stenosis using real time 3-dimentional transesophageal echocardiography

Abstract

Abstract Background Normal mitral annulus morphology is known to be saddle shape. There are a few reports regarding the relationship between flattening of the mitral annular saddle shape and mitral regurgitation. However, the relationship between aortic stenosis (AS) and mitral annulus morphology is unknown. Purpose To assess the impact of AS on mitral annular saddle shape using 3-dimentional transesophageal echocardiography. Methods A total of consecutive 83 subjects including 44 patients with severe AS (AS group) and 39 patients without AS (control group), who underwent real-time 3-dimentional transesophageal echocardiography of the mitral valve, were enrolled. The 3-dimentional geometry of the mitral annulus apparatus was evaluated by the parameters analyzed using dedicated quantification software such as anteroposterior diameter (APD), commissural width (CW), annular height (AH), mitral annulus (MA) area and annular height to commissural width ratio (AHCWR) as shown in Figure. We assessed the impact of severe AS on AHCWR, which is the key parameter showing flattening of the mitral annular saddle shape. These parameters were adjusted by body surface area (BSA). Exclusion criteria included left ventricular ejection fraction <50%, the presence of aortic regurgitation, mitral valve disease, pericardial or congenital diseases, endocarditis, cardiomyopathy, prior myocardial infarction, and paroxysmal or persistent atrial fibrillation. Results Comparisons of mitral valve geometry between AS group and control group are summarized in Table. AH/BSA and AHCWR were significantly lower in AS group compared with control group. Multiple linear regression analysis revealed severe AS to be a significant and independent predictor of lowering AHCWR (β=−0.39, t=−4.04, p<0.001) (adjusted with MA area, selected by stepwise analysis). Conclusions Severe AS might contribute to flattening of the mitral annular saddle shape, lead to the mitral annular structural remodeling. Assessment of the mitral annulus morphology might help evaluating severe AS. Mitral annulus 3-dimensional geometry Funding Acknowledgement Type of funding source: None