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Donor valves as substitutes for heart valve replacement.

The main problems of heart valve replacement in Sri Lanka are the cost of prosthetic valves and anticoagulant related complications. The use of human donor heart valves (homografts; allogeneic heart valves [AHV]) will alleviate these shortcomings. Recipients of AHV do not require anticoagulant therapy. Moreover, cryopreservation of AHV offers the opportunity for the storage of valves for an extended length of time with the preservation of valve integrity which is essential for their function after implantation. A donor valve bank can potentially provide diameter matched valves for recipients. Current research suggests that the adverse immunological reactions initiated by AHV cause tissue degeneration in a proportion of these implants. However, the grafts may be improved before implantation during the disinfection and storage of the valves. In this essay an overview on the advantages of using AHV, current concepts of valve banking, recent advances in the understanding of AHV immunogenicity, emerging techniques for immunomodulation of AHV and the possibility of setting up a donor heart valve bank in Sri Lanka are discussed.