An 8 year old, male castrated Bloodhound presented to the Cornell University Hospital for Animals Soft Tissue Surgery service for evaluation of a chest mass and nine month history of a progressive cough. The mass was identified on radiographs taken by the referring veterinarian. On presentation, the dog had a mildly increased respiratory rate and effort. Cardiothoracic auscultation revealed decreased to absent heart sounds over the left thorax, with a point of maximal intensity on the right. The dog also had decreased to absent lung sounds ventrally. Based on evaluation of three-view radiographs, a diagnosis of a Peritoneopericardial Diaphragmatic Hernia (PPDH) was made. Abdominal exploratory and surgical correction of the hernia was performed. Incidental findings of multifocal splenic myelolipomas, diffuse vacuolar hepatopathy of the right medial lobe, and loss of architecture of the quadrate lobe were found on histopathology. Four months following surgery, the patient was doing well.