Untargeted metabolomic profiling of dogs with myxomatous mitral valve disease and congestive heart failure shows metabolic differences associated with the presence of cardiac cachexia

OBJECTIVE To determine the effects of cardiac cachexia on the metabolomic profile in dogs with myxomatous mitral valve disease (MMVD).ANIMALS 3 groups of dogs with MMVD enrolled between November 30, 2018, and April 7, 2022: (1) Dogs with congestive heart failure (CHF) and cachexia (CHF-cachexia group; n = 10); (2) dogs with CHF that had no cachexia (CHF-no cachexia group; n = 10); and (3) dogs with asymptomatic disease (American College of Veterinary Internal Medicine [ACVIM] Stage B2) with no cachexia (B2 group; n = 10).METHODS Metabolomic profiles were analyzed from serum samples using ultra-high-performance liquid chromatography -tandem mass spectroscopy. Dogs in the 3 groups were compared, with statistical significance defined as P < .05 with a low false discovery rate (q < .10) and nominal statistical significance defined as P < .05 but q > .10.RESULTS Numerous metabolites were significantly (n = 201) or nominally significantly (n = 345) different between groups. For example, when comparing the CHF-cachexia vs CHF-no cachexia groups, lipids were the predominant metabo-lite differences, including many medium-and long-chain dicarboxylates and dicarboxylate acylcarnitines. For com- parisons of the CHF-cachexia vs B2 groups and the CHF-no cachexia vs B2 groups, amino acids, nucleotides, and cofactors/vitamins were the predominant metabolite differences.CLINICAL RELEVANCE Some significant metabolite differences were identified between dogs with and without cardiac cachexia.