Boxer cardiomyopathy. A review of the long-term benefits of antiarrhythmic therapy.

Antiarrhythmic therapy for Boxer cardiomyopathy both enhances the quality of life and improves life expectancy. The natural course of the disease for most dogs is a progression from mild arrhythmias to serious, potentially life-threatening arrhythmias and eventually to CHF. This process may evolve over a period of months or even years; the factors responsible for the variable rate of progression from one dog to another are not well understood. Once heart failure occurs, the long-term prognosis is dismal, usually no better than 3 to 6 months. Whether the administration of L-carnitine will have a significant effect on functional improvement of the heart, as taurine in dilatative feline cardiomyopathy, awaits the long-term evaluation of this therapy.