Long-term morphological changes in a cryopreserved pulmonary valve homograft.

Pulmonary homografts (PHs) are frequently used to replace the native pulmonary valve in the Ross procedure, and in the reconstruction of the right ventricular outflow tract. The case of a 25-year-old man whose PH was replaced 12 years after undergoing the Ross procedure is reported. The clinical cause of the PH failure was stenosis. Morphological studies showed cusp tissue degeneration with tears and calcification, as well as pannus growth on the flow and nonflow surfaces of the cusps and the pulmonary artery graft. The durability of this PH was likely due to a combination of low pressure on the right side of the heart and the patient's age at surgery.