Abstract 3387: The Effects of Restrictive Annuloplasty on Mitral Leaflet Coaptation and The Mechanism Regulating Functional Mitral Regurgitation: Simplified Echocardiographic Study
Objectives: The effects of restrictive annuloplasty on mitral leaflet coaptation in a clinical setting have not been fully elucidated. We developed a novel simplified method for assessing the actual degree of coaptation and investigated changes caused by its use. Based on our findings, we evaluated the direct effects of restrictive annuloplasty on mitral leaflet coaptation and the mechanism regulating mitral regurgitation.
Methods and Results: We studied 23 patients (mean 60 years old) with functional mitral regurgitation (grade 3 to 4+) with congestive heart failure (LV ejection fraction 32±10%) due to idiopathic (n=8) or ischemic (n=15) who underwent mitral valve repair with restrictive annuloplasty and 20 normal control subjects. We measured the septal-lateral diameter, tenting height, tenting area, and coaptation length of the mitral valve in 4-chamber, 2-chamber, and long-axis views at mid-systole before and after surgery using transthoracic and transesophageal echocardiography procedures. Coaptation length was calculated with the following formula: Ad-Ac, where Ad equals the whole length of the anterior leaflet during the diastolic phase and Ac equals the length of the non-coaptation free portion of the anterior leaflet at mid-systole. Coaptation length index was defined as the ratio of coaptation length to septal-lateral diameter.
Results: Tenting height and tenting area were significantly decreased, while coaptation length and coaptation length index were significantly increased (Table⇓). In multivariate analysis, coaptation length index showed a statistically significant negative correlation with degree of residual MR (r=0.77, p<0.0001) and was found to be the most reliable predictor of MR grade.
Conclusion: Our novel simplified method provided quantitative and morphological descriptions of mitral leaflet coaptation, and can also provide important information for developing a surgical strategy for regulation of MR.