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Otto et al 2020 ACC/AHA Guideline for the Management of Valvular Heart Disease

February 2, 2021 Circulation. 2021;143:e72–e227. DOI: 10.1161/CIR.0000000000000923 e98

CLINICAL STATEMENTS AND GUIDELINES including patient age, values, and preferences; expected bioprosthetic valve durability, avoidance of patient–prosthesis mismatch, and the potential need for and timing of reintervention; and the risks associated with long-term VKA anticoagulation with a mechanical valve replacement. Despite the significantly higher rate of bioprosthetic structural valve deterioration observed in younger versus older patients,7–11,14,15 many patients choose to avoid a mechanical prosthesis because 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 radiation exposure). The availability of TAVI has changed the dynamics of the discussion of the trade-offs between mechanical and bioprosthetic valves in younger patients16–19 (Table 22).

Recommendation-Specific Supportive Text

1.	 The choice of valve prosthesis in each patient is based on consideration of several factors, including valve durability, expected hemodynamics for valve type and size, surgical or interventional risk, the potential need for long-term anticoagulation, and patient values and preferences. The trade-off between the risk of reintervention for bioprosthetic valve deterioration and the risk of longterm anticoagulation should be discussed. Some patients prefer to avoid repeat surgery and are willing to accept the risks and inconvenience of lifelong anticoagulant therapy. Other patients are unwilling to consider long-term anticoagulation because of the inconvenience of monitoring, the attendant dietary and medication interactions, and the need to restrict participation in some types of physical activity. The incidence of structural deterioration of a bioprosthesis is greater in younger patients, but the risk of bleeding from anticoagulation is higher in older patients. In patients with shortened longevity and/or multiple comorbidities, a bioprosthesis might be more appropriate. In women who desire subsequent pregnancy, the issue of anticoagulation during pregnancy is an additional consideration (see pregnancy-related issues in Section 13.5).20,21 2.	 Anticoagulant therapy with VKA is necessary in all patients with a mechanical valve to prevent valve thrombosis and thromboembolic events. If anticoagulation is contraindicated or if the patient refuses VKA therapy, an alternative valve choice is appropriate. Newer anticoagulant agents have not been shown to be safe or effective in patients with mechanical heart valves. 3.	 Patients <50 years of age at the time of AVR incur a higher and earlier risk of bioprosthetic valve deterioration.4,10,14,22–24 Overall, the predicted 15-year risk of needing reoperation because of structural deterioration is 22% for patients 50 years of age, 30% for patients 40 years of age, and 50% for patients 20 years of age, although it is recognized that all bioprostheses are not alike in terms of durability.14 Anticoagulation with a VKA can be accomplished with acceptable risk in most patients <50 years of age, particularly in compliant patients with appropriate monitoring of INR levels. Thus, the balance between valve durability and risk of bleeding and thromboembolic events favors the choice of a mechanical valve in patients <50 years of age, unless anticoagulation is not desired, cannot be monitored, or is contraindicated. 4.	 Uncertainty and debate continue about which type of AVR is appropriate for patients 50 to 65 years of age. Newer surgical bioprosthetic valves may show greater freedom from structural deterioration, specifically in the older individual, although a high late mortality rate in these studies may preclude recognition of valve dysfunction.14–19 The risks of bleeding and thromboembolism with mechanical prostheses are low, especially in compliant patients with appropriate INR monitoring. Several studies have shown a survival advantage with a mechanical prosthesis in this age group. Alternatively, large retrospective observational studies have shown similar long-term survival rates in patients 50 to 69 years of age undergoing mechanical versus bioprosthetic valve replacement.22–24 In general, patients with mechanical valves experience a higher risk of bleeding caused by anticoagulation, whereas individuals who receive bioprosthetic valves experience a higher rate of reoperation because of structural deterioration of the prosthesis, as well as perhaps a decrease in survival rate.6,25–27 There are several other factors to consider in the choice of type of valve prosthesis (see Section 11.1). Ultimately, the choice of mechanical versus bioprosthetic valve replacement for all patients, but especially for those between 50 and 65 years of age, is a shared decision-making process that must account for the trade-offs between durability (and the need for reintervention), bleeding, and thromboembolism.1

5.	 In patients >65 years of age at the time of bioprosthetic AVR, the likelihood of primary structural deterioration at 15 to 20 years is only about 10%.28–31 In addition, older patients are at higher

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