For Percutaneous control of the degree of constriction after pulmonary artery banding, we developed an adjustable banding device that was operated by oil pressure. This consists of a stainless steel snare, a polyethylene tube with silicone oil, and a screw adjuster. Five dogs underwent banding of the pulmonary artery or the descending aorta with this device. This band could be effectively and finely adjusted. Although these studies are preliminary, they suggest that a reversible pulmonary artery band can be performed.