Fibrinous pericarditis in the horse.

This research article discusses a study on four adult horses that showed signs of congestive heart failure and were later found to have fibrinous pericarditis, an inflammation of a membrane surrounding the heart, with unsuccessful treatment attempts leading to their deaths.

Study Background

• The study was conducted over 18 months, from July 1978 to January 1980 at the New York State College of Veterinary Medicine.
• The subjects of the study were four adult horses that presented with symptoms suggestive of congestive heart failure. These symptoms included a significant muting of heart sounds, increased heart rate (tachycardia), swollen jugular veins (jugular vein distention), and swelling within peripheral tissues (peripheral edema).

Treatment and Outcome

• Treatments such as antibiotics, diuretics, and anti-inflammatory drugs were administered, but they proved unsuccessful.
• All four horses either passed away or had to be euthanized due to the severity of their condition.
• Post-mortem examinations (necropsies) were performed on all four horses. This process allowed the researchers to better understand the animals’ conditions.

Necropsy Findings

• In these necropsies, it was found that the horsess’ pericardial sac, the protective covering around the heart, was markedly distended or swollen with fluid.
• Thick layers of fibrin, a protein involved in blood clotting, were found uniformly deposited over the epicardium, the outer layer of the heart.
• This presents a clear picture of fibrinous pericarditis, an inflammation of the pericardium characterized by the deposition of fibrin.

Microbiological Investigations

• In three out of the four cases, the researchers tried to grow bacteria and viruses (culture) from the obtained pericardial fluid but were unsuccessful.
• In the fourth case, bacteriological culture of the pericardial fluid led to the isolation of Actinobacillus equuli, a bacterium known to cause variety of diseases in horses.
• However, it was not specified in the paper whether this bacterium was a definitive cause of the pericarditis seen in the fourth horse.