Cardiomyopathy in boxer dogs from the UK : a comparison between the arrhythmic and the myocardial dysfunction form

Abstract Objectives: To retrospectively compare and contrast the clinical presentation, diagnostic findings and survival in Boxer dogs with cardiomyopathy, with or without left ventricular (LV) systolic failure. Animals, materials and methods: Medical records of Boxers referred between 1993 and 2008 in which a diagnosis of ventricular arrhythmias and/or cardiomyopathy was made, were reviewed. Dogs were divided into two groups according to their left ventricular (LV) systolic diameter, groupAnormal (20 dogs) or group Bdilated (59 dogs). Results: Dogs in group A had a better outcome than dogs in group B (median survival time of 124 and 17 weeks respectively, p < 0.001). In group B, dogs with a history of collapse had a worse outcome (median survival time of 10 weeks) compared with dogs not showing collapse (median survival time 24 weeks) (p ¼ 0.031). Conclusions: The majority of dogs, in this UK study, presented with the myocardial dysfunction form of the disease, with LV dilation and congestive heart failure signs. The prognosis was worse in dogs with LV dilation compared to dogs with a normal LV and ventricular arrhythmias. In the Boxers with LV dilation, dogs with collapse had a worse prognosis than those without.