Retrospective Evaluation of Transcatheter Edge-To-Edge Mitral Valve Repair in Dogs With Myxomatous Mitral Valve Disease.

Abstract

BACKGROUND: Transcatheter edge-to-edge repair (TEER) is an emerging minimally invasive mitral valve repair treatment for dogs with myxomatous mitral valve disease (MMVD), but reports on its outcomes are limited. OBJECTIVE: Describe the clinical characteristics and complications in dogs with MMVD undergoing TEER. ANIMALS: Twenty client-owned dogs with MMVD stages B2, C, and D. METHODS: Retrospective case series. Cases were identified by review of hospital medical records between September 2023 and September 2024. RESULTS: Twenty dogs underwent TEER; of these, 13 (65%) survived. Seven dogs died within 9&#x2009;days because of mitral leaflet tear or single-leaflet device attachment (4/7 dogs, 57.1%), tracheal collapse (1/7 dogs, 14.3%), presumed post-procedure neurologic deficit with a history of hydrocephalus (1/7 dogs, 14.3%), and presumed cardiogenic shock (1/7 dogs, 14.3%). Significant reductions in vertebral heart score (11.6 [9.6-13.1] vs. 11.0 [8.3-11.9] vertebrae; p&#x2009;<&#x2009;0.01), vertebral left atrial size (2.90 [2.1-3.6] vs. 2.60 [2.0-3.3] vertebrae; p&#x2009;<&#x2009;0.01), left atrium-to-aortic root ratio (2.09 [1.5-2.5] vs. 1.69 [1.3-2.2]; p&#x2009;<&#x2009;0.05), left ventricular end-diastolic diameter normalized for body weight (2.1 [1.5-2.3] vs. 1.76 [1.4-2.2]; p&#x2009;<&#x2009;0.05), regurgitant fraction (77.83 [73.2-83.0] vs. 55.38 [20.5-73.6] %; p&#x2009;<&#x2009;0.05), and regurgitant volume (3.96 [2.1-6.2] vs. 1.25 [0.4-3.5] ml/kg; p&#x2009;<&#x2009;0.05) were observed 3&#x2009;months after TEER. CONCLUSIONS AND CLINICAL IMPORTANCE: Transcatheter edge-to-edge repair resulted in a significant reduction in left atrium and ventricle size and should be further investigated as a potential treatment option for dogs with MMVD.