ObjectiveThis study aimed to investigate the structure of the mitral valve in patients undergoing mitral valvuloplasty (MVP) using real‐time three‐dimensional transesophageal echocardiography (RT‐3D‐TEE). The main objective was to study the relationship between intraoperative annuloplasty ring size and mitral valve structure dimensions, with a focus on exploring the application value of RT‐3D‐TEE in MVP.MethodsA total of 28 patients with degenerative mitral regurgitation (DMR), who underwent MVP between February and September 2022, as well as 12 normal control cases, were enrolled in this study. The MV annulus and leaflets were quantitatively analyzed using MVN software.ResultsThe DMR group exhibited significantly greater dimensions in various parameters of the mitral valve, including the anterolateral‐to‐posteromedial diameter (DAlPm), anterior‐to‐posterior diameter (DAP), annulus height (HA), three‐dimensional annulus circumference (CA3D), two‐dimensional annulus area (AA2D), anterior leaflet area (Aant), posterior leaflet area (Apost), anterior leaflet length (Lant), posterior leaflet length (Lpost), and tenting volume (Vtent) compared to the control group.ConclusionReal‐time three‐dimensional transesophageal echocardiography provides valuable insights into the morphological structure of the mitral valve and lesion location. It can aid in surgical decision‐making, validate the success of MVP, and potentially reduce mortality and complications associated with mitral valve repair procedures.