Pulmonary valve sinus aneurysm associated with pulmonic stenosis and patent ductus arteriosus in a dog.

A three-year-old neutered female Bernese mountain dog was referred for evaluation of multiple congenital cardiac abnormalities. Transthoracic echocardiography demonstrated features consistent with type A pulmonic stenosis, including a normal pulmonary valve annulus, an increased transvalvular pressure gradient, systolic doming of thickened and fused pulmonary valve leaflets, and concentric right ventricular hypertrophy. Additionally, a focal aneurysmal dilation arising from the intermediate pulmonary valve leaflet was identified. Furthermore, a concurrent left-to-right shunting patent ductus arteriosus was detected. Computed tomography confirmed thickening of the pulmonic valve, narrowing of the sinotubular junction, and thin-walled, contrast-enhancing saccular dilation originating of the intermediate pulmonary valve sinus. These findings supported the diagnosis of a pulmonary valve sinus aneurysm associated with severe type A pulmonic stenosis and patent ductus arteriosus.