Morphological assessment of sucrose preservation for porcine heart valves.

Porcine aortic valves stored in various concentrations of sucrose (50-80%) for up to 52 weeks were examined both histologically and by electron microscopy. The valves were compared with porcine aortic valves stored in a nutrient and antibiotic medium for 12 weeks. Overall preservation was better in those porcine valves stored in sucrose solution than in nutrient and antibiotic medium, the best preservation being in 50% sucrose. Despite wide separation of collagen at that concentration seen on electron microscopy (not noted histologically), tissue preservation was good after storage in sucrose solutions at concentrations up to 80%, at which clumping of collagen and distortion of fibroblasts occurred. It is suggested that sucrose solution is acceptable for the long-term preservation of biological valves.