Abstract 16499: Quantitative Assessment of Mitral Valve Geometry in Patients with Degenerative Aortic Stenosis Using Real-Time 3D Transesophageal Echocardiography
Background: Although degenerative aortic stenosis (AS) is frequently associated with mitral annular calcification (MAC), its adverse impact on mitral valve function is not clear. We hypothesized that real-time 3DTEE could assess the extent and severity of MAC in 3D space, and investigate the relationship between MAC and mitral valve area (MVA).
Methods: To address this, 3D zoomed images of the mitral valve were acquired in 56 patients with degenerative AS and 24 body surface area matched control patients with normal aortic and mitral valve. Using Qlab-MVQ software (Philips), mitral annular points were traced in 8 cut planes rotated around the mitral annulus, and mitral annular area (outer MAA) was automatically calculated. The same measurements were accomplished for the inner area of mitral annulus (inner MAA) in the presence of MAC. MVA was calculated as left ventricular stroke volume divided by the velocity time integral of mitral valve inflow.
Results: Outer MAA in patients with AS was significantly larger compared to control subjects (5.5±1.0 vs. 4.8±0.8 cm2/m2, p<0.01). Inner MAA was significantly smaller in AS patients (3.8±1.2 cm2/m2) compared to control subjects (4.8±0.7 cm2/m2, p<0.001). Mitral valve calcification produced an average of 31% (range: 0% to 87%) reduction of MAA in AS patients. Mean pressure gradient across the mitral valve was significantly larger in patients with AS (1.7±1.4mmHg) than that in control subjects (0.7±0.3 mmHg, p<0.001), resulting in the smaller MVA in AS patients (1.7±0.6 cm2/m2) compared to control subjects (2.5±0.4 cm2/m2). Ten AS patients (18%) showed MVA≤1.5 cm2 , and 4 patients (7%) revealed MVA≤1.0 cm2 . A good correlation was noted between MVA and the ratio of inner MAA and outer MAA (r=0.74, p<0.001).
Conclusions: Significant MAC reduces actual annular area which is associated with further reduction of functional MVA in a subset of patients with AS. MAC in AS has an adverse impact on mitral valve function.
- © 2010 by American Heart Association, Inc.