Perspective Chapter: Role of Frozen Allografts in Aortic Valve Surgery

Abstract

Although, the mechanical and bioprosthetic valves, of good parameters, availability and easy of implantation, are universally applied as substitutes for failed aortic valve, the usefulness of aortic valve allografts (AVA); natural, viable, unstented human valves, is still considered. The essential technology for their preparation is cryopreservation, which allows for long-term storage. Hemodynamic functions of AVA are like of native valve, they do not produce hemolysis nor thromboembolism. Being markedly resistant for infection, AVA are recommended as the optimal grafts for severe endocarditis. Indeed, there exist some disadvantages, such as low availability, need for a specialized laboratories; implantation may be a challenge. Therefore, AVA are not recommended for routine use. Their important limitation is durability, affected with degenerative processes, characteristic of biological implants. Nevertheless, AVA presented satisfactory clinical results after 10, 20, and more years. This chapter have been discussed in detail the principal issues, connected with AVA, including preparation technologies, indications for use, surgical techniques, and first of all, clinical results.