Analysis of mitral valve morphology in dogs undergoing mitral valve repair with three-dimensional transesophageal echocardiography

Abstract Introduction Information about real-time three-dimensional (3D) transesophageal echocardiography (TEE) for the evaluation of canine mitral valve morphology is lacking in veterinary medicine. Objectives To evaluate the feasibility of 3D TEE for the evaluation of canine mitral valves and whether there was a difference in mitral valve morphology between American College of Veterinary Internal Medicine (ACVIM) stages. Animals Thirty-one dogs were evaluated, including nine dogs classified as ACVIM stage B2, 15 as stage C, and seven as stage D. Materials and methods Three-dimensional TEE was performed after anesthetic induction for mitral valve surgery, and the 3D geometry of the mitral valve apparatus was measured. Results The intraclass correlation coefficient was good in both inter- and intraobserver analyses of the 3D measurements of mitral valve annulus geometry and excellent in both inter- and intraobserver analyses in the 3D measurements of mitral valve annular and leaflet sizes. Annulus height to commissural width ratio of stage D dogs showed significantly lower values than B2 dogs (B2: 14.2% [9.1–20.5%]; C: 10.6% [6.5–24.1%]; D: 9.5% [4.7–13.8%]). The aortic–mitral angle of stages C and D were significantly flatter than stage B2 (B2: 122.32 ± 9.39; C: 133.66 ± 8.43; D: 140.70 ± 10.70). Conclusions Real-time 3D echocardiography using TEE is a feasible method to evaluate the morphology of the mitral valve in dogs. The saddle shape of the mitral annulus and aortic–mitral angle were flatter in stage D. Further studies are required to understand the pathology of mitral valve disease in dogs.