A 6-year-old, 35-kg, female spayed German wirehaired pointer was referred for evaluation of collapse/seizure-like activity and a suspected mediastinal mass. Echocardiographic examination revealed an obstructive, intraluminal aortic mass with aortic dissection. Gross and histopathological findings confirmed the aortic dissection with right pulmonary artery compression and an aortopulmonary fistula. The mass was histologically consistent with an intraluminal chondrosarcoma. To the authors knowledge this case represents only the second case of aortic chondrosarcoma in a dog, and interestingly the first case in either a dog or human to have aortic dissection associated with aortic obstruction by an intraluminal aortic tumor.
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