Purulent pericarditis as a sequela to clostridial myositis in a horse

Pericardial Disease, Myocardial Disease, and Great Vessel Abnormalities in Horses

Pericardial, myocardial, and great vessel diseases are relatively rare in horses. The clinical signs are often nonspecific and vague, or related to the underlying cause. Physical examination usually reveals tachycardia, fever, venous distension or jugular pulsation, a weak or bounding arterial pulse, ventral edema, and abnormal cardiac auscultation such as arrhythmia, murmur, or muffled heart sounds. The prognosis depends on the underlying cause and the disease progression, and ranges from full recovery to poor prognosis for survival. This article focuses on the etiology, diagnosis, prognosis, and treatment of pericarditis, pericardial mass lesions, myocarditis, cardiomyopathy, and great vessel aneurysm or rupture.

Pericardial effusion and congestive heart failure in a horse with multicentric lymphoma

A 20-year-old Warmblood mare was evaluated for acute-onset tachycardia and a one-week history of lethargy and ventral oedema. Haematology revealed leucocytosis with neutrophilia. Ultrasonographic examination revealed pericardial effusion and cardiac tamponade consistent with right-sided congestive heart failure. Abdominal ultrasonography demonstrated loss of definition of the right kidney and a structure adjacent to the kidney suggestive of a renal neoplasm. A tentative antemortem diagnosis of multicentric neoplasia, most likely lymphoma, was made. The horse was subjected to euthanasia due to a grave prognosis. Postmortem examination and histological evaluation were consistent with lymphoma, including infiltration of the cardiac muscle with neoplastic cells. Although lymphoma has been reported to affect the heart, congestive heart failure due to cardiac and pericardial neoplastic infiltration has not been previously reported as the presenting complaint. This case report describes the diagnostic approach to pericardial effusion and congestive heart failure in a mare with lymphoma.

Clostridial myonecrosis, haemolytic anaemia, hepatopathy, osteitis and transient hypertrophic cardiomyopathy after intramuscular injection in a Thoroughbred gelding

A 9-year-old Thoroughbred gelding was presented for swelling over the left neck and inappetence. There was recent history of intramuscular administration of flunixin meglumine into the left neck. On examination, there was evidence of focal myositis, anaemia, haemolysis and pigmenturia. Culture of aspirated fluid from the left side of the neck produced a heavy growth of a Clostridium species. Complications of infection included haemolytic anaemia, hepatopathy, osteitis and transient hypertrophic cardiomyopathy. Treatment included intravenous fluid therapy, antibiotics, anti-inflammatory drugs, blood transfusion and surgical debridement. There was complete resolution of clinical, haematological, biochemical and echocardiographic abnormalities, and the horse returned to ridden work. This report highlights the complications that can arise from clostridial myonecrosis, including the effect on the myocardium.