2014 年 47 巻 2 号 p. 41-46
A 7-year-old Golden Retriever with mild exercise intolerance and presence of an arrhythmia was referred to Nihon University. Electrocardiographic findings included wide QRS complexes, irregular R–R intervals, small irregular baseline undulations and no P waves. Thoracic radiography revealed a large mass of soft tissue opacity obliterating the cranial cardiac silhouette and the dilation of the pulmonary artery silhouette. Transthoracic echocardiography showed a type III pulmonary artery flow pattern, but it did not reveal the presence of a mass in the cranial mediastinum. Computed tomography angiography identified an enlarged right auricle that was consistent with a right auricular aneurysm in the region of the suspected mass. This case was therefore diagnosed with a right auricular aneurysm. These findings suggest that computed tomography angiography may be a useful diagnostic tool in the diagnosis of the right auricular aneurysm.