Objectives: The aim of this study was to report the long-term outcome of the surgical palliation of pulmonic stenosis in dogs.

Methods: The subjects comprised three female and six male dogs, mean (±sd) age: 23 (±25) months, mean (±sd) weight: 3·4 (±2·1) kg, diagnosed with severe pulmonic stenosis and right ventricular hypertrophy, with an average preoperative pressure gradient of 153 (±43) mmHg on echocardiography.

Results: The pressure overload with severe pulmonic stenosis was reduced by valvotomy, i.e., open pulmonary valve commissurotomy, with/without biomembrane patch grafting, under cardiopulmonary bypass. The postoperative pressure gradient at 1 to 7 days was significantly decreased to 65 (±39) mmHg (P<0·05). The reduced pressure gradient was maintained at 58 (±38) mmHg at final follow-up.

Clinical Significance: Open valvotomy, pulmonary valve commissurotomy and biomembrane patch grafting were effective in reducing obstruction in severe pulmonic stenosis in dogs.