Vegetative endocarditis on the pulmonary valve in a horse with weight loss, fever and heart murmur

Vegetative endocarditis is a rare cardiac pathology in horses, consisting on the formation of vegetative lesions over the cardiac valves or the endocardium due to an infection that is usually caused by bacteria or fungi. The clinical signs vary depending on the acuteness of the disease but include weight loss, fever, shifting lameness, distal limb edema, heart murmurs and sometimes signs of heart failure. We describe the case of a horse that presented to the hospital with a combination of fever, weight loss, distal limb edema and an orthopedic lesion. In the clinical exam a systolic heart murmur was audible over the area of auscultation of the pulmonary valve and echocardiography revealed an advanced vegetative endocarditis that affected the pulmonary valve. The horse was euthanized due to the poor prognosis of the combination of the endocarditis and the orthopedic lesion. Posmortem examination revealed a very important vegetative lesion over the pulmonary valve and histologic examination confirmed the diagnosis of endocarditis. Pulmonary valve endocarditis is particularly rare in horses and usually presents with a diastolic murmur. The particularities of this case, including the presence of a systolic murmur, are discussed.