Abstract
Cardiac neoplasms are uncommon, but secondary or metastatic neoplasms are relatively frequent, with an incidence 60 times higher than the primary ones. A particularly high frequency of metastatic cardiac involvement has been observed in lung squamous cell carcinomas, urinary tract tumors, and melanomas. However, the incidence is low because of breast tumors in dogs. Cardiac tumors may be symptomatic or, more commonly, an incidental finding observed during the investigation of unrelated problems. The clinical presentation is associated with that of a disseminated neoplasm, and cardiac metastases are generally asymptomatic but should be considered in patients with a history of neoplasia who present with impaired conduction, breathlessness, cardiomegaly, or arrhythmias. The present report aimed to describe a clinical case of cardiac metastasis of breast neoplasia in a dog in which we focusedon conservative clinical treatment and the importance of investigating the incidental clinical findings.