Short-Term Effects of Atorvastatin in Normal Dogs and Dogs with Congestive Heart Failure Due to Myxomatous Mitral Valve Disease

BACKGROUND: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) may improve heart failure class and survival in people with congestive heart failure (CHF) of various etiologies. HYPOTHESIS/OBJECTIVES: To evaluate the tolerability of atorvastatin in healthy dogs, and the short-term effects of atorvastatin on clinical markers of disease severity, lipid profiles, and markers of systemic inflammation and oxidative stress in dogs with CHF. ANIMALS: Eleven normal dogs and 12 client-owned animals with CHF attributable to myxomatous mitral valve disease. METHODS: Prospective nonblinded observational study. Normal dogs (n = 11) were first treated with atorvastatin and re-evaluated after 14 and 30 days for clinical tolerability and alterations in certain laboratory results. Subsequently, dogs with CHF (n = 12) were treated with atorvastatin at a dosage of 2 mg/kg q24 h for 8 weeks. Echocardiography, blood pressure (BP), quality of life questionnaire, and blood sampling were performed pre and post atorvastatin administration. RESULTS: Atorvastatin was well tolerated and did not result in apparent adverse effects or biochemical abnormalities in healthy dogs and in dogs with CHF. Healthy dogs experienced a decrease in total cholesterol (TC) concentration (P = .03) after atorvastatin administration. Decreases in TC concentration (P = .02), non-HDL cholesterol concentration (P = .02), total white blood cell count (P = .03), neutrophils (P = .01), and systolic BP (P = .01) were noted in the CHF group after 8 weeks of atorvastatin. CONCLUSIONS AND CLINICAL IMPORTANCE: Atorvastatin was well tolerated at clinically relevant doses in healthy dogs and dogs with CHF. Further investigation into the effects of statin treatment in dogs with CHF is warranted.