GLUTARALDEHYDE-FIXED BIOLOGICAL TISSUE CALCIFICATION - EFFECTIVENESS OF MITIGATION BY DIMETHYLSULFOXIDE

The conditions defining the extent of dimethylsulphoxide (DMSO) effect iveness in mitigating calcification of glutaraldehyde (GA)-fixed tissu e have been evaluated. Exposure of GA-fixed tissue porcine aortic valv e cusps to low concentrations of DMSO does not impart calcification in hibitory activity. Mitigation in calcification becomes evident only as the DMSO component nears 100% and is best when neat DMSO is used. In all instances, regardless of the DMSO concentration, exposure to DMSO resulted in an increase in the tissue shrinkage temperature, attribute d to further cross-linking in the tissue. Histological examination of samples before implantation indicate some deleterious effects to the t issue, the degree dependent on concentration, time and temperature of DMSO exposure, The results of this study suggest that treatment of GA- fixed tissue with high concentrations of DMSO for a short duration at a lowered temperature could give a bioprosthesis that has good mitigat ing calcification properties with retention of tissue integrity.