Impact of different annuloplasty rings on geometry of the mitral annulus with fibroelastic deficiency: the significance of aorto–mitral angle

We sought to investigate the impact of full annuloplasty rings versus C-shape bands on mitral annular geometry in the presence of fibroelastic deficiency (FED), as assessed by intraoperative three-dimensional transesophageal echocardiography (3DTEE). We retrospectively selected 65 patients who underwent mitral valve repair for severe mitral regurgitation caused by FED using full rings (the Ring group, n = 30) and C-shape bands (the Band group, n = 35). 71 controls without valvular heart disease were also included. Thorough 3DTEE inspections were performed for the entire cohort to measure morphological parameters of mitral annulus before and after surgery. Mid-term repair durability and left atrial diameter were followed up. The preoperative 3DTEE parameters, including annular diameters, area, height and aorto–mitral angle, were significantly larger in the FED groups than normal, and were comparable between two groups using different annuloplasty devices. After repair, the anterior–posterior diameter, annulus circumference and area were significantly larger in the Band group than in the Ring group. The aorto–mitral angle became comparable with normal value in the Ring group (p = 0.728), but not in the Band group (p = 0.011). Follow-up echocardiographic data showed a significant correlation between postoperative aorto–mitral angle and reduced left atrial diameter at 50.3 months after surgery (r = 0.63; p < 0.001). In conclusion, compared with C-shape bands, full rings may impose less narrowing on aorto–mitral angle, which correlates well with mid-term left atrial reverse remodeling.