Preservation of vein allograft viability during long-term storage

Background: The aim of this study was to compare the vein allograft viability following cryopreservation with that remaining after prolonged refrigerated storage. Materials and Methods: Great saphenous vein biopsies had been cryopreserved, and the samples were divided into two matched groups and stored in tissue culture medium for 42 days at + 4 degrees C, either with or without regular medium replacement. Each vein allograft was biopsied and assayed for viability every third day by the methyltetrazolium reduction assay. Viability indexes of vein allografts harvested from brain-dead multi-organ donors and from cadavers whose warm ischemic periods were maximally 24 h were also compared. Results: Vein allografts stored for 42 days at + 4 degrees C showed a similar viability (58.9 +/- 1.2%) to that of cryopreserved veins ( 59.7 +/- 2.3%). This was true even when cryopreserved and thawed allografts were subjected to 3 days of post-thaw incubation under presumably favorable conditions (58.7 +/- 1.6%). There was no viability index difference between the samples with medium replaced and not replaced and the specimens harvested from two different donor groups. Conclusions: Long-term storage of vein allografts at + 4 degrees C is a valuable option for regular banking practice. Sufficient amounts can be procured from cadavers similar to tissue donors. Copyright (C) 2005 S. Karger AG, Basel.