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[Indication for and the future of valvular bioprosthesis].

Two fundamental characteristics distinguish bioprostheses from mechanical prostheses: disadvantage: reoperation inevitable after a variable delay; advantage: the problems of anticoagulation are avoided in the majority of cases and, above all, thromboembolic complications are reduced, thus improving the quality of life even if anticoagulation proves necessary. Before weighing up these considerations and making the difficult choice of the best prosthesis, two factors must be taken into account: the advances in cardiac surgery have enabled surgical therapy to be considered even in asymptomatic patients with the object of ensuring longer and better quality life; the concept of reoperation is still too often synonymous with surgical failure whilst thromboembolic complications are referred to fatality. To delay reoperation is to significantly increase the risks, so falsifying the statistical mortality rate and making it impossible to answer the fundamental question: "does the use of bioprostheses prolong life expectancy compared to mechanical prosthesis?".