Pneumopericardium associated with a pulmonary-pericardial communication in a dog

A 6-year-old 18-kg (39-lb) spayed female Standard Poodle was referred for treatment of pneumopericardium. The dog did not have severe clinical signs relating to the pneumopericardium, and the diagnosis was made incidentally while investigating the cause of a cough. Computed tomography revealed an air-filled structure consistent with a bulla to the right of the heart base that appeared to communicate with the pericardial cavity Because spontaneous resolution of the pneumopericardium seemed unlikely and cardiac tamponade was a possibility, exploratory thoracotomy was performed. A lobulated bulla was found at the hilus of the right middle lung lobe adhered to the underlying pericardial sac, and a 4-cm-diameter communication from the pericardium to the pulmonary bulla was found. Right middle lung lobectomy was performed, and the pericardiotomy and pericardial opening were sutured. The dog recovered without complications. In previously reported cases of pneumopericardium involving a cat and a dog, the condition resolved spontaneously. In this dog, in contrast, surgical resection of the affected lung lobe with pericardial reconstruction was required for resolution of the pneumopericardium.