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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 e140

CLINICAL STATEMENTS AND GUIDELINES the dynamics of the discussion of the trade-offs between mechanical and bioprosthetic valves in younger patients (Table 22) (Figure 11).16–19

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 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.4,10,11,22–24 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.11 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.11,15–19 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 longterm 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 because of anticoagulation, whereas individuals who receive bioprosthetic valves experience a higher rate of reoperation attributable to structural deterioration of the prosthesis, as well as perhaps a decrease in survival rate.6,25–27 Several other factors should be considered in the choice of type of valve prosthesis (see Section 11.1). Ultimately, the choice of mechanical versus

Table 22.  Selected Factors That May Impact Shared Decision-Making for the Choice of Prosthetic Valve

Favor Mechanical Prosthesis Favor Bioprosthesis Age <50 y Increased incidence of structural

deterioration with bioprosthesis (15-y risk: 30% for age 40 y, 50% for age 20 y) Lower risk of anticoagulation

complications Age >65 y

Low incidence of structural

deterioration (15-y risk: <10% for age >70 y)

Higher risk of anticoagulation

complications

Patient preference (avoid risk of reintervention) Patient preference (avoid risk and inconvenience of anticoagulation) Low risk of long-term anticoagulation High risk of long-term anticoagulation Compliant patient with either home monitoring or close access to INR monitoring Limited access to medical care or inability to regulate VKA Other indication for long-term anticoagulation (eg, AF) Access to surgical centers with low reoperation mortality rate High-risk reintervention (eg, porcelain aorta, prior radiation therapy) Access to transcatheter ViV replacement Small aortic root size for AVR (may preclude ViV procedure in future) TAVI valves have larger effective orifice areas for smaller valve sizes (avoid patient–prosthesis mismatch) AF indicates atrial fibrillation; AVR, aortic valve replacement; INR, international normalized ratio; TAVI, transcatheter aortic valve implantation; ViV, valve-in-valve; and VKA, vitamin K antagonist.

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