Immunology and failure of valved allografts in children.

Valved allografts are frequently used in the repair of congenital heart defects in children. Although the longevity of these grafts is generally very good, there continue to be ongoing problems with allograft stenosis, allograft valve insufficiency, and subsequent allograft failure, particularly in younger children. This review presents data on the immunologic and nonimmunologic risk factors implicated in valved allograft failure, in addition to ongoing investigation into the improvement of allograft function.