Bilateral auricular aneurysm with intact pericardial sac in a dog

Abstract

A nine-year-old, male, Pekingese dog was presented with a history of dyspnea, lethargy, syncope, polyuria, polydipsia,
and selective appetite over two years. When the clinical signs first began, a radiographic exam revealed a radiopaque mass
in the cranial mediastinum. An adequate treatment was not performed and the dog was presented to the hospital with severe
tachycardia, dyspnea, and tachypnea, and died during physical examination. On necropsy, the heart presented bilateral
auricular aneurysms. The pericardial sac was intact, and no other defects were found within the heart. Microscopically, the
cardiomyocytes were marked degenerated and proliferation of connective tissue. This is the first case report of a bilateral
auricular aneurysm with intact pericardial sac in a dog.