Surgical valvulotomy for tricuspid valve stenosis in a dog.

A 2-year, 4-month-old neutered female Labrador retriever was brought for evaluation of right-sided congestive heart failure. Echocardiographic examination revealed tricuspid valve dysplasia with only two small orifices in the valve resulting in severe tricuspid stenosis. The dog underwent a right fifth lateral intercostal thoracotomy and surgical tricuspid valvulotomy, under cardiopulmonary bypass. The stenosis was relieved by dividing the valve leaflets between the two orifices with continuation to the commissures, creating a 'bileaflet' valve. The dog made a good recovery initially, with echocardiography at 48 h after surgery showing a reduction in tricuspid valve E and A wave velocities and pressure half-time (from 230 ms to 65 ms). She was discharged five days after surgery, and spironolactone, benazepril, pimobendan, and clopidogrel were prescribed. The dog was re-presented two days later having collapsed, with pyrexia, facial swelling, and pitting edema on the ventral neck and intermandibular region. Investigations did not reveal an underlying cause, and the clinical signs resolved with supportive therapy. Two years after surgery, the dog was free of clinical signs with normal exercise tolerance and only mild tricuspid regurgitation on echocardiography, with discontinuation of all medications.