Relationship of Mitral Annular Remodeling to Severity of Chronic Mitral Regurgitation

Hypotheses (1) Mitral regurgitation (MR) severity is directly associated with mitral annular remodeling as evidenced by mitral annular enlargement. (2) Increasing severity of chronic MR will result in symmetric enlargement of the mitral annulus as measured by annular shape indices. Background Limited data exist on mitral annular remodeling for patients with MR. Identification of annular changes may be important in aiding surgical repair. Methods The mitral annulus was measured in several planes using transthoracic echocardiography in 173 patients: trace to no MR (34), mild MR (48), moderate MR (45), and severe MR (46). Patients were subgrouped by mechanism of MR and annular shape indices were determined. Results With increasing MR severity, there was a corresponding symmetric increase in all systolic and diastolic measurements, but no significant differences in annular shape indices between subgroups by MR severity or by MR mechanism. Conclusions Mitral annular remodeling is symmetric, regardless of degree or mechanism of MR.