Table 6.3 Summary: Clinical evaluation of horses with tricuspid regurgitation


Variable signs noted by owners depending on the severity of the condition:

incidental finding (usually)

poor exercise tolerance (uncommon)

right-sided congestive heart failure (very uncommon)

Clinical findings

Clinical signs are rarely noted

Most commonly found in racehorses presented for poor athletic performance, but frequently an incidental finding even in these animals

Grade 2-6/6 plateau-type pan or holosystolic murmur with a PMI over the right apex area

Murmur may radiate to left side of the chest in the 2nd ics

Endocarditis rarely affects this valve

Evaluation of significance

Most likely to be significant if:

associated with poor athletic performance weak or variable pulse quality

resting heart rate >45bpm

intensity grade 4/6 or greater widespread radiation

associated with more significant valvular disease such as MR

associated with abnormal arrhythmia, especially atrial fibrillation (uncommon), APCs

associated with signs of right-sided congestive heart failure (dependant oedema, jugular filling)

jugular pulsation is present

Helpful diagnostic tests


Electrocardiography if arrhythmia present

Evaluation of other body systems is indicated in investigation of poor athletic performance using diagnostic tools such as endoscopy