Double-Outlet Right Ventricle for Relief of Pulmonic Stenosis in Dogs An Experimental Study

Relief of right ventricular outflow obstruction with a valveless Dacron conduit from the right ventricle to pulmonary artery was accomplished in 12 normal dogs. The procedure involved the development of a surgical technique without cardiopulmonary bypass, hypothermia, and/or venous occlusion; the development of a ventricular coring instrument; the fabrication of a wire supported Dacron conduit; the development of a basketed insert cannula; and the creation of an experimental model of pulmonic stenosis. Of the 12 dogs operated, two died intraoperatively, three died postoperatively, and seven were electively euthanized postoperatively. Relief of the right ventricular outflow obstruction was documented in all cases by a reduction in mean peak right ventricular pressure, improvement of mean arterial pressure, decrease in mean right atrial pressure, and an increase in mean pulmonary artery pressure. The pulmonary insufficiency created was considered a tolerable although not benign condition. The technique would be of particular value in dogs with severe right ventricular hypertrophy.