Flow-mediated vasodilation measurements in Cavalier King Charles Spaniels with increasing severity of myxomatous mitral valve disease.

Background: Cardiovascular disease is associated with endothelial dysfunction in humans and studies of plasma biomarkers suggest that dogs with myxomatous mitral valve disease (MMVD) might also have endothelial dysfunction.

Hypothesis: That progression of mitral regurgitation (MR) is associated with development of endothelial dysfunction.

Animals: Forty-three Cavalier King Charles Spaniels (CKCS) with MR of varying severity.