Application of a Fresh Decellularized Pulmonary Allograft for Pulmonary Valve Replacement in Japan

Tissue engineering has advanced the technique of decellularization of the heart valve. The valve is reseeded with the patient's own cells after implantation with suppression of immunologic reactions. The same advantage has been reported for fresh decellularized heart valves, and more than 10 years of excellent outcomes have been achieved. We began performing such heart valve implantations in 2013 as part of a clinical study at Osaka University. We report our evaluation of the safety and efficacy of heart valve implantation.

Human pulmonary valves from the German Society for Tissue Transplantation (n=2) or from Japanese heart transplant recipient heart (n=4) were used to make decellularized heart valves; the decellularization process was the same as that used in Europe. Valves were implanted in 5 adults with pulmonary valve insufficiency after tetralogy of Fallot repair and in 1 infant with a double-outlet right ventricle with pulmonary stenosis. Postoperative echocardiography and cardiac magnetic resonance imaging revealed that the valve and ventricular function were significantly improved and maintained postoperatively.

Decellularized heart valves could be the new material used as artificial heart valves. Pulmonary allografts derived from the hearts of heart transplant recipients are considered to be useful material for decellularized heart valves. The application of this valve to Japanese clinical circumstances and using the hearts of heart transplant recipients is considered to be very significant.