Calcification of glutaraldehyde-fixed porcine xenograft.

Abstract
The clinical and light and electron microscopic findings are reported in a 14-year-old patient who died 12 months after mitral valve replacement with a Hancock prosthesis. Severe cusp calcification had led to immobilisation of the valve and stenosis. Calcification involved the substance of the valve cusps. The cause of the calcification in this patient is unknown.