Objective-Minimally invasive repair of mitral valve prolapse (MVP) causing severe mitral regurgitation (MR) should reduce mitral regurgitation and have chronic durability. Our ex-vivo, acute in-vivo, and chronic in-vivo studies suggest that direct application of radiofrequency ablation (RFA) to mitral leaflets and chordae can effect these repair goals to decrease MR.Methods-A total of seven canines were studied to assess the effects of RFA on mitral valve structure and function. RFA was applied ex-vivo (n=1), acutely in-vivo using a right lateral thoracotomy and cardiopulmonary bypass (n=3), and chronically in-vivo using percutaneous access to the heart (n=3). RFA was applied to the mitral valve and its associated chordae. Mitral valve structure and function (in-vivo preparations) were then assessed.Results-Ex-vivo application of RFA resulted qualitative reduction in mitral leaflet surface area and chordal length. Acute in-vivo application of RFA to canines found to have MVP causing severe MR demonstrated a 43.7-60.7% statistically significant (p=0.039) reduction in postablation MR. Chronic, in-vivo, percutaneous application of RFA was found to be feasible and the engendered alterations durable.Conclusion-These data suggest that myxomatous mitral valve repair using radiofrequency energy delivered via catheter is feasible.