Heart Sac Inflammation (Pericarditis) in Cats

Pericarditis is a rare disease in cats that can be hard to diagnose and is potentially life threatening. Cats who have experienced infection elsewhere in the body (such as the mouth or lungs) are at greater risk. Cats that are suspected of having pericarditis require immediate veterinary attention.

The severity of pericarditis depends on the stage of development when diagnosed. Complications can occur the longer it is allowed to develop.

Mild pericarditis responds well to medical management, but is seldom discovered before complications develop.

Left untreated, pericarditis develops into pericardial effusion, an accumulation of fluid inside the pericardium. In more severe cases, the pressure put on the heart by pericardial effusion results in cardiac tamponade, a scenario where the fluid build-up within the pericardium prevents the heart from beating. Cardiac tamponade often results in sudden death.

In some cases, pericarditis develops into constrictive pericarditis, where the inflammation causes scarring to develop, thickening the pericardium. Once it becomes too thick, the pericardium is no longer flexible enough to properly adapt to the heart’s movements, leading to suppression of the heart beat.

Pericarditis is an inflammation of the pericardium, which is the thin membrane around the heart.

The causes of pericarditis include:

• Bacterial, parasitic, fungal, viral or protozoal infection that begins elsewhere in the body, such as in the mouth or the lungs, and then travels to the pericardium
• Bacterial, parasitic, fungal, viral or protozoal infection of the pericardium directly due to injury
• Heart disease
• Heart tumors, particularly lymphoma and sarcoma
• Idiopathic

The symptoms of pericarditis are subtle and sometimes go unnoticed.

Diagnostic tools to identify pericarditis and the underlying cause include:

• Physical examination
• Blood work
• Culture of the fluid extracted from inside the pericardium to determine the nature of the infection
• Diagnostic imaging, including x-rays and ultrasound
• Electrocardiogram

Treatments include:

• Repeated draining of pericardial fluid
• Antibiotics, antiparasitics, antivirals, or antifungals as appropriate
• Surgery to remove part of the pericardium
• Chemotherapy in the case of cancer

Most animals undergoing treatment for pericarditis require hospitalization.

In cases where the inflammation is detected and treated early, the prognosis is fair. However, in most cases pericarditis remains unnoticed until it has advanced to a critical level. Cats with pericarditis that are left untreated have a guarded prognosis. In cases where pericardial effusion or cardiac tamponade develop, prognosis is poor.

There are no proven preventative measures for pericarditis.

Pericarditis is rare in cats.

• Hospitalization
• Antibiotics, antiparasitics, antivirals, or antifungals
• Surgery