For patients <50 years of age who do not have a contraindication to anticoagulation and require AVR, it is reasonable to choose a mechanical aortic prosthesis over a For patients 50 to 65 years of age who require AVR and who do not have a contraindication to anticoagulation, it is reasonable to individualize the choice of either a mechanical or bioprosthetic AVR with consideration of individual patient factors and after informed In patients >65 years of age who require AVR, it is reasonable to choose a bioprosthesis over a mechanical valve.1 In patients <50 years of age who prefer a bioprosthetic AVR and have appropriate anatomy, replacement of the aortic valve by a pulmonic autograft (the Ross procedure) may be considered at a Comprehensive Valve Synopsis Shared decision-making about the choice of pros- thetic valve type is influenced by several factors, CLINICAL STATEMENTS AND GUIDELINES including patient age, values, and preferences; ex- pected bioprosthetic valve durability, avoidance of pa- tient prosthesis mismatch, and the potential need for and timing of reintervention; and the risks associated with long-term VKA anticoagulation with a mechani- cal valve replacement. Despite the significantly higher rate of bioprosthetic structural valve deterioration ob- served in younger versus older patients,7 11,14,15 many patients choose to avoid a mechanical prosthesis be- cause they are unwilling to consider long-term VKA therapy because of the inconvenience of monitoring, dietary restrictions, medication interactions, and the need to restrict participation in some types of athletic activity. A mechanical valve might be a prudent choice for patients for whom a second surgical procedure would involve very high risk (eg, those with prior ra- diation exposure). The availability of TAVI has changed the dynamics of the discussion of the trade-offs be- tween mechanical and bioprosthetic valves in younger (Table 22). Recommendation-Specific Supportive Text 1. 