In the 2017 report from the California Office of Statewide Health Planning for patients who underwent mitral-valve replacement and were 40 to 69 years of age, receipt of a biological prosthesis was associ- ated with a mortality rate significantly higher than that seen with receipt of a mechanical prosthesis.1 The choice of a mechanical mitral valve in patients <65 years of age who are good candidates for anticoagulation should account for these observa- tional, nonrandomized data and abide by the prin- ciples of shared decision-making.1,7,10 7. Hazards associated with anticoagulation increase with age, and rates of structural valve deterioration decline significantly. In patients >65 years of age, the ratio of valve durability to life expectancy supports the use of a bio- prosthetic mitral valve replacement, which allows avoidance of the risks of long-term VKA anticoagulation in these older patients. In 1 Figure 11. Prosthetic valves: choice of biopros- thetic versus mechanical valve type. Colors correspond to Table 2. *Approximate ages, based on US Actuarial Life Expectancy tables, are provided for guidance. The balance between expected patient longevity and valve durability var- ies continuously across the age range, with more durable valves preferred for patients with a longer life expectancy. Bioprosthetic valve durability is finite (with shorter durability for younger patients), whereas mechanical valves are very durable but require lifelong anticoagulation. Long-term (20-y) data on outcomes with surgical bioprosthetic valves are available; robust data on transcatheter bioprosthetic valves extend to only 5 y, leading to uncertainty about longer-term outcomes. The deci- sion about valve type should be individualized on the basis of patient-specific factors that might af- fect expected longevity. See Section 3.2.4.2 for a discussion of the choice of TAVI versus SAVR. 