2016 ACVIM Forum Research Abstract Program

Our results indicate that corin expression might be a rate-limiting step in dogs with CHF due to MMVD. A lack of an increase in corin expression or activation can be postulated to be a possible important pathophysiological mechanism responsible for the natriuretic peptide paradox in dogs with CHF, and warrants further investigation. Figure 1 : Quantitative corin expression in myocardial tissue in control dogs, and in dogs with congestive heart failure secondary to myxomatous mitral valve disease. Aims of this study were to determine feasibility and repeatability of measuring anatomical regurgitant orifice area (AROA) using real-time 3D transthoracic echocardiography (RT3DE) in dogs affected by MMVD, and to determine if AROA obtained using RT3DE relates to the severity of MMVD assessed both with an echocardiographic scoring system (MRSS) and the American College of Veterinary Medicine (ACVIM) staging system. RT3DE datasets of the mitral valve were acquired in 81 privately owned dogs diagnosed with MMVD and AROA was traced and measured using dedicated software. Dogs were classified as mild, moderate or severe according to an echocardiographic MRSS, and as ACVIM Stage B1, B2 or C. Technique feasibility (as % of dataset measurable) and inter-and intra-operator repeatability were assessed. Differences in AROA between dogs in different MRSS and ACVIM stages were investigated.