Three-dimensional changes in mitral valve annulus geometry in organic and functional mitral regurgitation: insights for mitral valve repair

Abstract

Background: Assessment of changes in mitral valve annulus (MVA) geometry according to mitral regurgitation (MR) etiology is key to select most effective annulus reshape for MV repair. Objectives: Study purpose was to assess MVA changes in organic and functional MR in comparison to normal (N) subjects, by transthoracic 3D echocardiography (3DE). Methods: 30 pts with moderate-severe organic MR (OMR) due to MV prolapse (57±14 yrs, 21 men) and 29 pts with moderate-severe functional MR (FMR) (61±13 yrs, 21 men) were compared to 30 N age-, gender- and body size-matched. Subjects underwent 3D full-volume acquisition of MV. MVA geometry was analyzed at mid-systole with prototype dedicated software (TomTec MV assessment 2.0). Results: Compared to N, both OMR and FMR pts had larger MVA and leaflet size (Table). MVA was more ellipsoidal in OMR pts than in N, due to larger increase in anterolateral-posteromedial (AL-PM) diameter than in antero-posterior (A-P) diameter (sphericity index (SI) correlated inversely to AL-PM diameter: r=-0.45, p=0.013); even though enlarged, FMR had no significant change in sphericity. MVA non-planarity angle and angle between MVA and aortic annulus (Ao-AP) were similar in N vs OMR, but significantly wider in FMR. Tenting height and volume were similar to N in OMR, and significantly higher in FMR. View this table: MVA comparison in N, OMR and FMR Conclusion: Quantitative analysis by 3DE revealed significant differences in MVA between OMR and FMR. While MVA shape is preserved in organic MR, it is severely affected in functional MR.