Research Communications of the 24th ECVIM-CA Congress

We examined 87 dogs with MMVD (25 Normal, 9 B1, 40 B2 and 13 C) presented for cardiac evaluations by 2D echocardiography. Left atrial linear and area dimensions in right parasternal short and long axis views were obtained at 3 time points -early diastole (LA MAX ), just prior to mitral valve opening, at the onset of atrial systole (LA P ) and just prior to mitral valve closure (LA MIN ). We calculated 4 indices of LA function: total LA emptying fraction (LA TEF ), active LA emptying fraction (LA ACT ), passive LA emptying fraction (LA PAS ) and LA reservoir function (LA RES ) for all 4 sets of measurements. We examined the differences in selected LA function indices between different disease stages with a Kruskal Wallis Test with post-hoc multiple comparisons. We also examined the diagnostic accuracy of selected indices of LA function in differentiating dogs in Stage B2 and Stage C (CHF) using ROC analysis.