Methods for the operative management of patent ductus arteriosus are now well established, and in the vast majority of children the circulatory shunt can be safely and effectively abolished by dividing the ductus or by closing it in continuity with ligatures and transfixing sutures. In adults, however, closure of patent ductus arteriosus may pose important technical problems, particularly when there are associated pulmonary hypertension, calcification, aneurysm and infective endocarditis. Under these circumstance, division or ligation is unusually hazardous because the diseased vessels often fracture or tear when sutures are placed in them. Then we closed the patent ductus arteriosus by use of cardiopulmonary bypass in 18 patients and ligated the ductus via thoracotomy in 18 patients from Jan. 1986 to May 1990. And we compared the results between two different methods. We concluded that ligation of ductus had a problem of rupture and transpulmonary internal suture closure of PDA had a problem of injury of recurrent laryngeal nerve.