Arrhythmogenic right ventricular dysplasia/cardiomyopathy in a Siberian husky

A seven-month-old male Siberian husky was presented with a recent history o f anorexia, hindlimb weakness and syncope. Physical examination revealed se vere tachycardia, tachypnoea and dyspnoea. Mucous membranes were pale and f emoral pulses were weak, An electrocardiogram showed sustained ventricular tachycardia with a left bundle branch block configuration. Thoracic radiogr aphs revealed slight right ventricular enlargement and two-dimensional echo cardiography revealed mild right ventricular dilation at the cardiac apex a nd some hyperechogenic areas on the right side of the interventricular sept um. Administration of intravenous lignocaine converted the ventricular tach ycardia to sinus rhythm. The maintenance antiarrhythmic therapy consisted o f oval procainamide and propranolol. Three weeks later the dog died suddenl y. On postmortem examination, the right ventricular free wall was very thin at the apex, infundibulum and caudal aspect of the right ventricular parie tal wall, similar to the 'triangle of dysplasia' of human patients, Histopa thological examination revealed replacement of several areas of right ventr icular free wall myocardium with connective tissue and fat. The right atriu m and left ventricle were less severely affected by the same lesions. The c linical and pathological findings are similar to those reported in young pe ople with arrhythmogenic right ventricular dysplasia/cardiomyopathy.