A simplified echocardiographic measurements of direct effects of restrictive annuloplasty on mitral valve geometry

Objective: The purpose of this study was to evaluate the direct effects of restrictive mitral annuloplasty on mitral valve geometry.

Methods: We studied 23 patients (mean age: 63 ± 5 years) with functional mitral regurgitation (moderate to severe) and advanced cardiomyopathy (ejection fraction: 25 ± 8%) with ischemic (n = 15) or nonischemic (n = 8) conditions, who underwent restrictive annuloplasty. We determined annular septal-lateral diameter, tenting height, tenting area, vertical length of coaptation of the mitral leaflets (coaptation length), and ratio of coaptation length to septal-lateral diameter (coaptation length index) at end-systole, before and after surgery, using transthoracic echocardiography.

Results: Annular septal-lateral diameter, tenting height, and tenting area were significantly decreased (34 ± 7 to 20 ± 5 mm, P < 0.05; 9 ± 4 to 5 ± 2 mm, P < 0.05; 210 ± 120 to 80 ± 50 mm(2) , P < 0.05, respectively), whereas coaptation length and coaptation length index were significantly increased (3.4 ± 1.3 to 6.5 ± 2.9 mm, P < 0.05; 0.11 ± 0.06 to 0.33 ± 0.15, P < 0.05, respectively). Spearman's rank correlation analysis revealed that these five variables had a statistically significant correlation with the degree of mitral regurgitation. Furthermore, stepwise regression analysis showed that coaptation length index, in contrast to coaptation length, was the most important correlate with the degree of mitral regurgitation.

Conclusion: Our simplified parameters were useful for quantitative and geometrical descriptions of mitral valve geometry, and may also provide important information for developing a surgical strategy for functional mitral regurgitation.