Medical management of congestive heart failure in a horse.

This study reports on the treatment of a 4-year-old horse suffering from congestive heart failure, atrial fibrillation, and mitral regurgitation. The treatment involved using digoxin and furosemide, and the horse showed improvement but remained unsuitable for athletic work.

Detailed Explanation

• The research is focussed on a specific case of a 4-year-old Quarter Horse gelding diagnosed with atrial fibrillation, mitral regurgitation, and signs of bilateral congestive heart failure. The horse was given medical treatment, and the research outlines its response to it.
• The horse’s treatment involved both intravenous (directly into the bloodstream) and oral administration of digoxin, a medication used to treat heart conditions. It was combined with furosemide, a diuretic used to reduce fluid build-up in the body, a symptom of heart failure.
• The initial process to increase the concentration of digoxin in the horse’s system is called parenteral digitalization, following which the daily maintenance dose was continued in oral form. The administered dosage was 21.7 micrograms/kg of body weight, which achieved a steady-state serum digoxin concentration of 2.3 ng/ml without causing toxicosis (digoxin poisoning).
• As clinical improvements were observed, the dosage of furosemide was gradually reduced and eventually stopped. The clinical signs of congestive heart failure were managed, and a normal (sinus) rhythm was occasionally established in the horse’s heart, however, it was considered unfit for future athletic work.
• Following 35 days of therapy, a cardiac catheterization was performed, a procedure to assess the heart’s condition. Subsequently, due to various medical and ethical considerations, the horse was euthanized.
• The post-mortem examination revealed marked dilation in all chambers of the heart, fibrosis of the mitral valve, and jet lesions in the left atrium, underlining the severe cardiac condition of the horse.
• Based on this single case study, the researchers suggested that orally administered digoxin might be a useful treatment for managing congestive heart failure in selected equine patients.