Balloon valvuloplasty in 30 dogs with pulmonic stenosis: Effect of valve morphology and annular size on initial and 1-year outcome

Case records of 30 dogs in which valvular pulmonic stenosis (PS) was treate d by balloon dilation were reviewed retrospectively. Physical examination, thoracic radiographs, 9-lead ECG, echocardiography, and Doppler studies wer e performed in all dogs. Two-dimensional and Doppler echocardiography were repeated after 24 h and I year after treatment. Dogs were divided into 2 gr oups based on their valvular anatomy on echocardiography and aortic: pulmon ary ratio: 18 had type A PS with normal annulus diameter and aortic: pulmon ary ratio less than or equal to1.2, and 12 had type B PS with pulmonary ann ulus hypoplasia and aortic: pulmonary ratio >1.2. Most dogs in the type B g roup were brachycephalic and had no poststenotic dilatation on thoracic rad iographs. Of the dogs with type A stenosis, 100% survived valvuloplasty wit h resolution of clinical signs. At 1-year follow-up, 94.4% were still alive and remained asymptomatic. Of those with type B stenosis, 66.6% had favora ble outcome postvalvuloplasty. At 1-year follow-up, 66.6% of dogs were aliv e, and resolution of clinical signs was obtained in 50%, This study reveale d the immediate and long-term efficacy of balloon valvuloplasty in dogs wit h PS.