Cutting balloon and high-pressure balloon dilation for palliative treatment of congenital double-chambered right ventricle and primary infundibular stenosis in a Golden retriever dog.

Combined cutting balloon and high-pressure balloon dilation was performed in a dog with a double-chambered right ventricle and severe infundibular stenosis of the right ventricular outflow tract. The peak systolic pressure gradient across the stenosis decreased by 65% after dilation (from 187 mmHg before to 66 mmHg after) affirming the intervention as successful. However, early re-stenosis occurred within 3 months leading to exercise intolerance, exercise-induced syncope, and right-sided congestive heart failure. Cutting balloon followed by high-pressure balloon dilation provided temporary but not long-term relief of right ventricular obstruction in this dog.