Combined cutting balloon and conventional balloon angioplasty in a dog with supravalvular pulmonary stenosis

A 7-year-old Miniature Schnauzer presented with exercise intolerance and easy fatigability. Echocardiography revealed the presence of supravalvular pulmonary stenosis. The peak velocity through the stenosis was 6.4 m/sec, and the interventricular septum was flattened. Cutting balloon angioplasty was designed for the treatment of coronary artery stenosis, which was resistant to conventional balloon angioplasty. Accordingly, the dog underwent cutting balloon angioplasty and conventional balloon dilation. One month after treatment, it showed neither exercise intolerance nor easy fatigability. The ventricular septum flattening disappeared. Five months later, the dog showed an increase in activity. Two years later, the peak velocity through the stenosis decreased to 4.4 m/sec. Neither clinical symptoms nor restenosis was observed. Thus, supravalvular pulmonary stenosis was successfully treated using this combination method. The present case showed that combined cutting balloon and conventional balloon angioplasty is a useful and minimally invasive treatment for supravalvular pulmonary stenosis.