Echocardiographic detection of pulmonic valve rupture in a horse with right-sided heart failure.

Pulmonic valve rupture was determined to be the cause of severe right-sided heart failure in a 20-year-old Thoroughbred gelding. A flail in the intermediate pulmonic valve cusp was detected by 2-dimensional echocardiography. Significant pulmonic and tricuspid valvular regurgitation were confirmed by Doppler echocardiography. Despite treatment, the horse's condition deteriorated, and euthanasia was performed. At necropsy, a tear in the pulmonary artery extending into the right valve cusp and a tear at the base of the intermediate valve cusp were identified at the junction of the right and intermediate pulmonic valve cusps. Careful echocardiographic evaluation of the pulmonic valve is warranted for horses with right-sided heart failure, for which more common causes cannot be found.