Is physiologic annular dynamics preserved after mitral valve repair with rigid or semirigid ring?

Background: Various rings are available to achieve more physiologic mitral valve repair from viewpoints of physiologic mitral annular structure or dynamics. We evaluated preoperative and postoperative mitral annular structures and dynamics.

Methods: Thirty-six patients underwent mitral valve repair for degenerative mitral insufficiency. Carpentier-Edwards Physio II ring (semirigid [Edwards Lifesciences, Irvine, CA]), St. Jude Medical Rigid Saddle Ring (RSR [St. Jude Medical, St. Paul, MN]), and MEMO 3D ring (semirigid [Sorin SpA, Milan, Italy]) were implanted in 13, 12, and 11 patients, respectively. Intraoperative real-time three-dimensional transesophageal echocardiography was performed before and after repair.

Results: The postoperative anteroposterior diameter reduction rate from end diastole to end systole was significantly (p<0.0001) larger in MEMO (9.58%±2.91%) than in Physio II (0.98%±1.04%) and RSR (1.94%±1.95%). There were no significant differences in the commissure-to-commissure diameter reduction rates among the groups: 0.81%±1.98% for Physio II, 0.12%±0.53% for RSR, and 0.51%±1.98% for MEMO. The postoperative end-systolic annular height commissure width ratio was significantly (p<0.0001) larger in both Physio II (17.9%±3.0%) and RSR (18.5%±1.6%) than in MEMO (13.6%±3.0%). The postoperative annular height commissure width ratio increase rate from end diastole to end systole was significantly larger in MEMO (5.1%±2.3%) than in Physio II (0.1%±0.6%) and RSR (0.3%±0.5%).

Conclusions: Physio II and RSR could restore the physiologic three-dimensional annular shape, but the annular motion was diminished. Conversely, MEMO could preserve both the anteroposterior movement and folding dynamics, but no three-dimensional restoration of the mitral annulus was obtained.