Acid hydrolyzable XXXX in long-term stored commercial bioprosthetic heart valves implications for @entity730 .

@entity3584 @entity406 @entity730 @entity3125 @entity460 @entity35 @entity291 @entity264
There is evidence that @entity3584 used routinely in the fixation process of bioprosthetic heart valves may be a major factor in their subsequent @entity730 . A further complication is introduced by the use of a @entity406 treatment step, whether for sterilization or storage. The effects of this second @entity264 on @entity730 is also unknown. The aim of the present work is to determine the degree of @entity3584 and @entity406 incorporation into commercial valve leaflets and to establish whether there is a relationship between the @entity264 treatment and tissue @entity730 . Both pre- and post-implantation concentrations of @entity3125 were estimated by high performance liquid chromatography of acid hydrolyzates of commercial valve tissue. Control samples were taken from freshly prepared porcine aortic valves and @entity291 pericardium fixed in @entity3584 . The degree of @entity730 was investigated using the @entity35 subcutaneous implant model. Samples were retrieved after 56 days and @entity460 estimated by atomic absorption spectroscopy. The results indicated that storage of both porcine and pericardial valves for periods of 5 years or longer reduced @entity730 . A greater reduction in @entity730 was noted when tissue was treated sequentially with @entity3584 and @entity406 rather than @entity3584 alone. From this work it can be concluded that bioprosthetic valves calcify less in the @entity35 model when they are stored for extended periods of time in @entity3584 solution. This effect is enhanced when @entity406 storage is employed.
