Research Communications of the 27(th) ECVIM-CA Congress: Intercontinental, Saint Julian's, Malta, 14th to 16th September 2017

Disclosures: No disclosures to report. Micro ribonucleic acids (miRNAs) are short RNA molecules which regulate gene expression. They show a varying expression in many diseases, including heart disease. miRNAs are stable and detectable from blood. Therefore, they are potential biomarkers. Myxomatous mitral valve disease (MMVD) is the most common heart disease in dogs. In the long preclinical phase, progressive degeneration of the mitral valve leads to eccentric left-ventricular and -atrial hypertrophy, eventually succeeded by congestive heart failure and death. We aimed to investigate the expression of miR-NAs in blood plasma of dogs in consecutive stages of MMVD. 183 miRNAs were quantified from blood plasma using RT-qPCR in 10 dogs passing 3 stages of MMVD (modified CHIEF stage B1, B2, and C2/C3). One-way repeated measures ANOVA and pairwise comparisons using Benjamini-Hochberg-correction showed significant differences (P < 0.05) in expression within 3 miRNAs: cfa-miR-92b was downregulated in MMVD stage C2 compared to stage B1 and B2 by the factor of 0.52 and 0.61, respectively. cfa-miR-92a and cfa-miR-1306 were downregulated in MMVD stage C2 compared to stage B1 by the factor of 0.60 and 0.53, respectively. There was no significant difference between any other stages.