[Midterm restenosis of freestyle valved conduit in an adult tetralogy of Fallot].

We report a case of midterm restenosis of freestyle valved conduit implanted between the right ventricle and the pulmonary artery. A 69-year-old woman visited our hospital with dyspnea and general fatigue and was diagnosed as tetralogy of Fallot. Total corrective surgery including patch closure of ventricular septal defect was performed using the freestyle valve with the Hemashield prothesis to reconstruct the right ventricle to the pulmonary artery. The catheterization revealed almost normal right ventricular pressure on 40th postoperative day, but the opening of the valve was limited. Twenty-two months later she visited our hospital with severe right heart failure. The pressure gradient over the valve was 122 mmHg and the leaflet of the freestyle valve was markedly thickened causing severe stenosis. Use of the freestyle valve for the right ventricular out flow tract reconstruction has to be further studied.