Tricuspid regurgitation

Veterinary advice should be sought before applying any treatment or vaccine.

Tricuspid Regurgitation

Tricuspid Valve Regurgitation

Tricuspid regurgitation (TR) is a type of cardiac heart murmur which is frequently found in Thoroughbred and Standardbred racehorses. Incidences and severity of TR increase with the horse's age and level of training.
TR involves the leakage of blood backwards through the tricuspid valve, into the right atrium, occurring with every contraction made by the right ventricle. The additional blood present in the right atrium causes it to enlarge and pump harder.

Horses with severe mitral regurgitation and pulmonary hypertension associated with congestive heart failure as well as (less commonly) horses with severe respiratory disease can develop TR.


Poor performance


  • History
  • Clinical signs
  • Physical exam
  • Echocardiography



Treatment is typically not needed, unless signs of congestive heart failure are also present
Annual echocardiographic reexamination for horses with moderate to severe TR



Favorable in horses with trace or mild TR if they have no evidence of valvular pathology or mild valve prolapse, right-sided cardiomegaly, pulmonary hypertension or atrial fibrillation.

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