Longitudinal Analysis of Quality of Life, Clinical, Radiographic, Echocardiographic, and Laboratory Variables in Dogs with Preclinical Myxomatous Mitral Valve Disease Receiving Pimobendan or Placebo: The EPIC Study. Academic Article uri icon


  • BACKGROUND: Changes in clinical variables associated with the administration of pimobendan to dogs with preclinical myxomatous mitral valve disease (MMVD) and cardiomegaly have not been described. OBJECTIVES: To investigate the effect of pimobendan on clinical variables and the relationship between a change in heart size and the time to congestive heart failure (CHF) or cardiac-related death (CRD) in dogs with MMVD and cardiomegaly. To determine whether pimobendan-treated dogs differ from dogs receiving placebo at onset of CHF. ANIMALS: Three hundred and fifty-four dogs with MMVD and cardiomegaly. MATERIALS AND METHODS: Prospective, blinded study with dogs randomized (ratio 1:1) to pimobendan (0.4-0.6mg/kg/d) or placebo. Clinical, laboratory, and heart-size variables in both groups were measured and compared at different time points (day 35 and onset of CHF) and over the study duration. Relationships between short-term changes in echocardiographic variables and time to CHF or CRD were explored. RESULTS: At day 35, heart size had reduced in the pimobendan group: median change in () LVIDDN -0.06 (IQR: -0.15 to +0.02), P<0.0001, and LA:Ao -0.08 (IQR: -0.23 to +0.03), P<0.0001. Reduction in heart size was associated with increased time to CHF or CRD. Hazard ratio for a 0.1 increase in LVIDDN was 1.26, P=0.0003. Hazard ratio for a 0.1 increase in LA:Ao was 1.14, P=0.0002. At onset of CHF, groups were similar. CONCLUSIONS AND CLINICAL IMPORTANCE: Pimobendan treatment reduces heart size. Reduced heart size is associated with improved outcome. At the onset of CHF, dogs treated with pimobendan were indistinguishable from those receiving placebo.

published proceedings

  • J Vet Intern Med

altmetric score

  • 4.2

author list (cited authors)

  • Boswood, A., Gordon, S. G., Hggstrm, J., Wess, G., Stepien, R. L., Oyama, M. A., ... Watson, P.

citation count

  • 38

complete list of authors

  • Boswood, A||Gordon, SG||Häggström, J||Wess, G||Stepien, RL||Oyama, MA||Keene, BW||Bonagura, J||MacDonald, KA||Patteson, M||Smith, S||Fox, PR||Sanderson, K||Woolley, R||Szatmári, V||Menaut, P||Church, WM||O'Sullivan, ML||Jaudon, J-P||Kresken, J-G||Rush, J||Barrett, KA||Rosenthal, SL||Saunders, AB||Ljungvall, I||Deinert, M||Bomassi, E||Estrada, AH||Fernandez Del Palacio, MJ||Moise, NS||Abbott, JA||Fujii, Y||Spier, A||Luethy, MW||Santilli, RA||Uechi, M||Tidholm, A||Schummer, C||Watson, P

publication date

  • December 2017