Pulse duplicator study of the right ventricular outflow tract: changes induced by surgery.

Thirty-one adult pig hearts were studied in a pulse duplicator to observe the changes induced by right ventricular outflow tract reconstruction. Six were normal hearts, 7 had a transannular outflow patch and 18 a composite monocusp patch inserted. Abnormal movements and distortion of the posterior pulmonary leaflets were observed when a patch had been inserted. The monocusp patch achieved a competent pulmonary valve although the bovine pericardial cusp had slower movements than the normal leaflet, resulting in a mild regurgitation.