Cell viability of aortic allografts after long-term cryopreservation and clinical application to aortic root replacement in a patient with aortitis.

A key point in the establishment of a tissue cryopreservation system is to maintain cell viability for an extended period. The viability of the tissue cells in the authors' cryopreservation system was examined, and the first clinical application reported. The tissue culture method demonstrated 95% of rat aortas (21 of 22 specimens) and 88% of human cardiac valves (seven of eight) to be viable after 6.4 months and 5.8 months of cryopreservation, respectively. The first clinical case, a 54-year-old man with aortic valve replacement and complications of aortitis, underwent successful aortic root replacement. Whereas the use of allografts in aortitis cases is controversial, such an approach was assumed reasonable because the mechanical stress between the native aortic annulus and the inserted valve could be reduced by aortic root replacement with the allograft.