Abstract 16457: 4D- Echocardiographic Analysis of Degenerative Mitral Valve: Annular Dynamics are Deranged in Myxomatous Degeneration
Background Myxomatous disease is generally considered to be a disease of the leaflets, with preserved annular function. As such, flexible annuloplasty devices are routinely utilized to stabilize the annulus during mitral valve (MV) repair with the intent of preserving annular dynamics. We hypothesize that the mitral annulus in myxomatous disease is abnormal, and has deranged dynamic motion.
Methods Thirty patients [Normal MV (NMV) = 14, Myxomatous MV (MMV) = 16] underwent transesophageal acquisition of full volume rt-3DE images. A mid-systolic frame was selected for the initiation of annular tracking using 4D-MV Assessment© - 2.0 (TomTec, Munich, Germany) to generate annular parameters for the entire cardiac cycle. Cardiac cycle duration was normalized to align MV opening (early diastole) and MV closing (early systole) and annular data was interpolated at 100 points during the cardiac cycle. Systolic rate of change in annular dimensions was calculated.
Results MMR annuli are significantly larger than NML group - midsystolic circumference = 14.0 ± 1.8 cm vs. 10.1 ± 1.1 cm (p <0.001, Fig A), and area = 14.5 ± 4.0 cm2 vs. 7.25 ± 1.5 cm2, (p< 0.001, Fig B) respectively. Annuli in the MMV group enlarge more rapidly as compared to the NMV annuli during systole. Maximum rate of increase for septolateral diameter, anterolateral-posteromedial diameter, annular circumference (Figure C), and annular area (Figure D) in the MMV group was 0.04±0.02 mm/s, 0.03±0.01 mm/s, 0.08±0.03 mm/s and 0.16±0.06 mm2/s as compared to 0.03±0.01mm/s (p=0.03), 0.01±0.01 mm/s (p=0.001), 0.05±0.02 mm/s (p=0.002), and 0.07±0.04 mm2/s (p=0.0001) respectively in the NMV group.
Conclusion: In myxomatous degeneration, the mitral annulus dilates rapidly in early systole in response to rising ventricular pressure, suggesting that there is inherent annular pathology in these patients. Thus, complete annular remodeling using rigid annuloplasty rings should be preferred in MMV for annular stabilization.
- © 2011 by American Heart Association, Inc.