Objective: Information about congestive heart failure (CHF) treatment in the horse is limited. Torsemide, an oral loop diuretic, is increasingly used in humans, dogs, and cats with CHF. Torsemide is well absorbed and induces diuresis in healthy horses, and its use in a horse with CHF has been reported. This retrospective descriptive study aimed to describe the use of torsemide in equids with CHF.
Animals: 12 equids (10 horses, 1 miniature donkey, and 1 mule).
Clinical presentation: Horses presented to a referral practice with clinical signs of congestive heart failure. Diagnosis was confirmed with echocardiography. Treatment with torsemide as well as other cardiac medications was instituted. The cases were evaluated and monitored with physical examinations, clinicopathologic data, and repeat echocardiograms.
Results: Torsemide (PO, q 12 h [median 0.5 mg/kg; IQR, 0.5 to 0.5 mg/kg; range, 0.25 to 1 mg/kg]) was well tolerated in the 12 cases. There were improvements in heart rate and respiratory rate and increases in plasma creatinine concentration (median, 1.3 vs 1.9 mg/dL) that followed therapeutic interventions that included torsemide. Median survival time of equids with CHF treated with torsemide was 189 days (IQR, 10 to 348.25 days; range, 2 to 806 days), with 2 distinct clusters. Four cases were euthanized within 2 weeks after starting treatment, while 8 survived longer than 137 days or are currently alive.
Clinical relevance: Torsemide can be used in equids diagnosed with CHF without serious adverse events and has the potential to be a useful oral diuretic. The nature of the study does not allow us to conclude that torsemide had a causal relationship with clinical progression.
Keywords: atrial fibrillation; echocardiography; equine; loop diuretic; mitral valvular regurgitation.