Peritoneal-pericardial diaphragmatic hernia in cats

© Rand, J (2006) Problem-based feline medicine. Saunders Elsevier, Sydney

Persistent communication occurs between the pericardial and peritoneal cavities because of abnormal fusion of the septum transversum with the pleuroperitoneal folds durng development. The hernia can be of variable size. The most likely organs to be herniated are the liver and gallbladder, small intestine, spleen and stomach.

Clinical signs

Signs are mostly related to the gastrointestinal system and include vomiting, diarrhoea and weight loss. Most cases are asymptomatic and it is an incidental finding. An increased incidence in Persian cats is suspected.

Physical examination is often normal. In some cases, the heart sounds may be muffled. In symptomatic patients, respiratory signs can be present, particularly under stressful conditions.

Diagnosis

Radiographs show extreme enlargement of the 'cardiac' silhouette. Dorsal displacement of the trachea is usually visible. There is also silhouetting of the caudal border of the heart within the diaphragm. Heterogeneous densities of the 'cardiac' silhouette is due to varied contents of the pericardial cavity. Abdominal radiographs may show an absent or smaller than normal liver.

On ECG, the only change may be a shifting of the mean electrical axis.

Treatment

Surgery for PPDH should be reserved for patients showing clinical symptoms as complications post-operatively can be considerable.