This is a fortunately uncommon bacterial condition, primarily of the heart valves but also of the heart muscle. Bacteria enter the blood stream from wounds or infections elsewhere in the body, invading the heart valves where they produce cauliflower-like masses called vegetations. Vegetations break off, spreading in the circulation and infecting other parts of the body. Gum disease is one possible source of bacteria. Pets on immunosuppressants including corticosteroids have an increased risk of bacterial infection.
Clinical signs may include, lethargy, loss of appetite, fever, shaking, lameness and personality changes. There is usually a heart murmur, often changing in intensity from day to day. Chest x-rays, ECG but especially echocardiography are used to confirm a diagnosis. A blood culture identifies the bacteria and its antibiotic sensitivity.
An appropriate antibiotic, selected according to bacterial culture, is given intravenously for the first week (through an indwelling cannula). Oral antibiotic therapy continues long-term. We monitor affected individuals closely. Repeat x-rays and echocardiography shows the vegetations shrinking in size. Even so, the prognosis is guarded. Congestive heart failure may occur at any time.