1. Chemical treatment of heart valve bioprostheses utilizing sodium dodecylsulfate is, according to experimental findings, the optimum at the present time since this treatment inhibits the development of calcification, increases hemocompatibility, and reduces immunogenicity of the biotissue as compared with the standard method (treatment with 0.625% glutaric aldehyde). 2. Treatment of bioprostheses with sodium dodecylsulfate does not solve the root problem of biotissue calcification.