Survival in cats with primary and secondary cardiomyopathies

Feline cardiomyopathies (CM) represent an heterogeneous group of myocardial disease. The most common CM is Hypertrophic Cardiomyopathy (HCM), followed by Restrictive Cardiomyopathy (RCM). Studies comparing survival and outcome in different group of CM are scant. Furthermore, few is known about the cardiovascular consequences of systemic diseases on survival. Objectives: Aim of this retrospective study was to compare survival and prognostic factors in cats affected by HCM, RCM or secondary CM referred in our institution over a 10 year period. Methods The study included 94 cats with complete case record and echocardiographic exam. 50 cats presented HCM, 14 RCM and 30 secondary CM. Results A statistically significant different survival time was identified for cats with HCM (median survival time of 865 days), RCM (273 days) and secondary CM (less than 50% cardiac death rate). In the overall population and in the primary CM group (HCM+RCM), risk factors in the multivariate analysis, regardless of the CM considered, were: presence of clinical signs, an increased LA/Ao ratio and presence of hyper coagulable state Conclusions and relevance: primary CM in cats share some common features (LA dimension and hypercoagulable state) linked to feline cardiovascular physiology, which influence greatly survival in end stage CM. The presence of clinical signs has to be regarded as a marker of disease severity, regardless of the underlying CM. Secondary CM are more benign conditions, but if the primary disease is not properly managed, prognosis might be poor also in this group of patients.