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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 e148 CLINICAL STATEMENTS AND GUIDELINES 11.4 Excessive Anticoagulation and Serious Bleeding With Prosthetic Valves Recommendations for Management of Excessive Anticoagulation and Serious Bleeding in Patients With Prosthetic Valves Referenced studies that support the recommendations are summarized in Online Data Supplement 37. COR LOE Recommendations 2a C-LD 1. For patients with mechanical valves and uncontrollable bleeding who require immediate reversal of anticoagulation, administration of 4-factor prothrombin complex (or its activated form) is reasonable. 2a C-LD 2. For patients with mechanical valves and uncontrollable bleeding who have received 4-factor prothrombin concentrate complex, adjunctive use of intravenous vitamin K is reasonable if resumption of VKA therapy is not anticipated for 7 days. 2a B-NR 3. For patients with bioprosthetic valves or annuloplasty rings who are receiving a direct oral anticoagulant and who require immediate reversal of anticoagulation because of uncontrollable bleeding, treatment with idarucizumab (for dabigatran) or andexanet alfa (for anti-Xa agents) is reasonable.1–5 2b C-LD 4. For patients with a mechanical prosthetic valve and supratherapeutic INR (>5.0) who are not actively bleeding, the benefit of individualized treatment with oral vitamin K, in addition to temporary withdrawal of the VKA, is uncertain. Synopsis Excessive VKA anticoagulation greatly increases the risk of hemorrhage. However, a rapid decrease in INR to a subtherapeutic level may increase the risk of thromboembolism.6 Nevertheless, for patients who require immediate reversal of VKA anticoagulation because of severe or life-threatening bleeding or the need for an emergency procedure, reversal is indicated.7 Preference is placed on the use of rapid-acting and reliable agents, such as prothrombin complex concentrate or its activated form. Addition of vitamin K can be considered on an individual basis.8–13 Specific antidotes are available to reverse the effects of dabigatran (idarucizumab) and the oral anti-Xa (andexanet alfa) anticoagulants. Recommendation-Specific Supportive Text 1. Four-factor prothrombin complex concentrate includes factors II, VII, IX, and X. Onset of effect is within 5 to 15 minutes, and duration of effect is 12 to 24 hours. It is a more specific and reliable reversal agent than fresh frozen plasma.8 2. Vitamin K is a cofactor for hepatic production of factors II, VII, IX, and X. Onset of effect depends on the route of administration (intravenous versus oral), and the dose given should be predicated on the presence of active bleeding, the maintenance dose of the VKA, the magnitude of INR elevation, and the desired range into which to reduce the INR.7,9–11 A 10-mg intravenous dose is recommended for lifethreatening bleeding when there is no concern for restarting the VKA within the next week. 3. Idarucizumab (two, 2.5-mg bolus infusions no more than 15 minutes apart) is indicated to reverse the effect of dabigatran when clinically indicated.1,5 Andexanet alfa (bolus and 2-hour infusion, with the dose dependent on the timing of exposure and the individual agent) is used to reverse the effect of the oral anti-Xa agents. Experience with these agents is accumulating.2–4 Prothrombin complex concentrate (or its activated form) has also been used with direct oral anticoagulant–related bleeding. 4. A systematic review of the effectiveness and safety of administering vitamin K to patients receiving VKA therapy with an INR between 4.5 and 10.0 and without bleeding indicated a nonsignificant increased risk of mortality and thromboembolism with vitamin K administration, with only moderate certainty of the evidence. Patients receiving vitamin K had a nonsignificant increase in the likelihood of reaching goal INR, with very low certainty of the evidence. The findings suggested that patients on VKA therapy who have an INR between 4.5 and 10.0 and are not bleeding are not likely to benefit from routine vitamin K administration in addition to temporary VKA cessation.13 11.5 Thromboembolic Events With Prosthetic Valves Recommendations for Management of Thromboembolic Events With Prosthetic Valves COR LOE Recommendations 2a C-EO 1. In patients with a mechanical AVR who experience a stroke or systemic embolic event while in therapeutic range on VKA anticoagulation, it is reasonable to increase the INR goal from 2.5 (range, 2.0–3.0) to 3.0 (range, 2.5–3.5) or to add daily low-dose aspirin (75– 100 mg), with assessment of bleeding risk. 2a C-EO 2. In patients with a mechanical mitral valve replacement who experience a stroke or systemic embolic event while in therapeutic range on VKA anticoagulation, it is reasonable to increase the INR goal from 3.0 (range, 2.5–3.5) to 4.0 (range, 3.5–4.0) or to add daily low-dose aspirin (75–100 mg), with assessment of bleeding risk. 2b C-EO 3. In patients with a bioprosthetic surgical or transcatheter aortic valve or bioprosthetic mitral valve who experience a stroke or systemic embolic event while on antiplatelet therapy, VKA anticoagulation, instead of antiplatelet therapy may be considered after assessment of bleeding risk.1,2 Synopsis For patients with a mechanical valve who suffer an embolic event, it is important to assess the adequacy Downloaded from http://ahajournals.org by on October 7, 2026