OBJECTIVES Myxomatous mitral valve disease (MMVD) presents a frequent heart problem in dogs. The inodilator pimobendan has shown to increase survival time of affected dogs when compared to the ACE inhibitor benazepril. The objective of this study was to estimate the cost-effectiveness of pimobendan compared to generic benazepril for treatment of MMVD in dogs in Germany. METHODS A Markov model was developed to calculate costs and benefits of pimobendan and benazepril over a 1-year time horizon in dogs with MMVD on concurrent furosemide treatment. The model structure allowed for a differentiation in costs and transition probabilities between treatment start and maintenance treatment, and included the health states asymptomatic MMVD, symptomatic MMVD, treatment failure, euthanasia, and sudden death. Most transition probabilities were based on randomized controlled trials. Input-data on treatment pattern were derived from published literature, and cost data taken from official price and tariff lists (year 2008, perspective of the dog owner). Missing data were obtained from experts in canine cardiology. RESULTS Over the 1-year time horizon, mean total therapy cost per dog on pimobendan was € 463.55 versus € 284.29 for benazepril. Mean survival was 274 days and 129 days for dogs on pimobendan and benazepril, respectively; resulting in a cost of € 1.24 for each additional day of life on pimobendan. Mean costs per treatment day were lower with pimobendan (€ 1.69) when compared to benazepril (€ 2.20). Extensive one-way and probabilistic sensitivity analyses confirmed the robustness of the results. CONCLUSIONS Pimobendan is a cost-effective treatment of MMVD if the dog owner is willing to pay a price below the normal range of food costs in Germany for each additional day of life. Lower total treatment costs for benazepril are merely attributed to a shorter survival, as pimobendan resulted in less costs per treatment day compared to benazepril.