Abstract 13415: Mitral Annular Dynamics in Mitral Annular Calcification: Evaluation With Real-time 3D-Echocardiography
Background: Mitral valve anatomy and physiology are complex. 2D-Echocardiography is of limited value in their evaluation. Using real-time 3D echocardiography, we sought to describe the changes that occur in the calcified annulus (MAC) when compared with normal controls.
Methods and Results: 43 MAC subjects were compared with 42 age, sex, and BMI-matched controls. Mitral annular area, anteroposterior [AP] and intercommissural [IC] diameters, height, and height/IC ratio (a measure of the saddle shape of the valve) were measured throughout the cardiac cycle with dedicated quantification software (figure).
Compared to normal controls, the calcified annulus was similar in size (average diastolic area = 7.8 ± 1.8 cm2 vs. 7.2 ± 1.5 cm2, p=0.16) but flatter (diastolic height = 2.84 ± 1.22 cm vs. 3.54 ± 0.98 cm, p = 0.007). Annular contraction was reduced in MAC subjects, largely due to decreased contraction along the AP diameter (3 ± 7% vs. 10 ± 9%, p = 0.0006). Height/IC ratio in early systole was less when MAC was present (0.09 ± 0.06 vs. 0.13 ± 0.04, p = 0.002) indicating less systolic accentuation of the saddle shape than normal. Finally, early systolic tenting volume was greater in MAC patients (2.11 ± 1.28 mL vs. 1.46 ± 0.83 mL, p = 0.008) and tenting decreased insignificantly from early to late systole in MAC subjects (mean difference = 0.28 mL, p = 0.29) while there was a significant decrease in controls (mean difference = 0.65 mL, p < 0.0001). Among MAC subjects, 2 had moderate and 2 had mild mitral regurgitation; all others had trace or no regurgitation.
Conclusions: The calcified mitral annulus is flatter and less dynamic than normal, displaying reduced annular height and decreased contraction, particularly along the AP diameter. In addition, the normal systolic accentuation of the saddle shape is lost as is the normal systolic reduction of leaflet tenting.
- © 2013 by American Heart Association, Inc.