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

Circulation. 2021;143:e72–e227. DOI: 10.1161/CIR.0000000000000923 February 2, 2021 e147 CLINICAL STATEMENTS AND GUIDELINES

2a C-LD 4.  For patients with bioprosthetic heart valves or annuloplasty rings who are receiving anticoagulation for AF, it is reasonable to consider the need for bridging anticoagulant therapy around the time of invasive procedures on the basis of the CHA2DS2-VASc score weighed against the risk of bleeding.

2a C-LD 5.  For patients who are undergoing invasive procedures and have 1) a mechanical AVR and any thromboembolic risk factor, 2) an older-generation mechanical AVR, or 3) a mechanical mitral valve replacement, bridging anticoagulation therapy during the preoperative time interval when the INR is subtherapeutic is reasonable on an individualized basis, with the risks of bleeding weighed against the benefits of thromboembolism prevention.

Synopsis

The management of patients with prosthetic heart valves or repaired native valves in whom interruption of anticoagulant therapy is needed for diagnostic or surgical procedures should take into account the type and location of the valve, the type of procedure, thromboembolic risk factors, the length of time over which oral anticoagulation will be withheld, and bleeding risk. “Bridging” therapy with either intravenous unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) has evolved empirically to reduce thromboembolic events during temporary interruption of oral anticoagulation in higher-risk patients, such as those with a mechanical mitral valve replacement or AVR and additional risk factors for thromboembolism.1

Recommendation-Specific Supportive Text

1.	 Antithrombotic therapy should not be stopped for procedures in which bleeding is unlikely or would be inconsequential if it occurred (eg, surgery on the skin, dental cleaning, or simple treatment for dental caries). Eye surgery, particularly for cataracts or glaucoma, is usually associated with very little bleeding and thus is frequently performed without alteration of anticoagulation with a VKA. 2.	 In patients with a bileaflet mechanical AVR and no other risk factors, the risk of thromboembolism after stopping anticoagulation with a VKA is small if the drug is withheld for only a few days. In these low-risk patients, the inconvenience and expense of bridging anticoagulation can be avoided. When it is necessary to interrupt VKA therapy, the agent is stopped 2 to 4 days before the procedure and restarted as soon as bleeding risk allows, typically 24 hours after surgery.2,3 3.	 In patients with mechanical valves on long-term VKA therapy who require emergency surgery or invasive procedures, anticoagulation can be reversed by administration of intravenous prothrombin complex concentrate. It replaces the coagulation factors that are decreased by VKAs and contains all coagulant factors, including II, VII, IX, and X, in inactivated form. Onset of effect is within 5 to 15 minutes, and duration of effect persists for 12 to 24 hours. With fresh frozen plasma, onset of effect is longer (1–4 hours), and duration of effect is shorter (<6 hours), depending on the dose given. The effect of prothrombin complex concentrate can be prolonged with vitamin K, if indicated.4

4.	 Although the large phase III trials comparing NOACs with warfarin excluded patients with moderate to severe rheumatic MS or mechanical heart valves, some did include patients with other VHD and bioprosthetic valve replacement or repair.5 Many patients who develop an indication for anticoagulation late after bioprosthetic heart valve replacement or native valve repair are treated safely with direct oral anticoagulants, as predicated on their CHA2DS2-VASc score and the predicted risks of bleeding. Considerations about the need for bridging therapy in these individuals can follow the same strategy applied to other subsets of patients who have AF without moderate to severe rheumatic MS or a mechanical prosthesis. 5.	 When interruption of oral VKA therapy is deemed necessary, the agent is usually stopped 3 to 4 days before the procedure and is restarted postoperatively as soon as bleeding risk allows. Bridging anticoagulation with intravenous UFH or subcutaneous LMWH is started when the INR falls below the therapeutic threshold (ie, 2.0 or 2.5, depending on the clinical context), usually 36 to 48 hours before surgery, and is stopped 4 to 6 hours (for intravenous UFH) or 12 hours (for subcutaneous LMWH) before the procedure. There are no randomized comparative-effectiveness trials evaluating a strategy of bridging versus no bridging in adequate numbers of patients with prosthetic heart valves who need temporary interruption of oral anticoagulant therapy, although such studies are ongoing. The evidence cited to support bridging therapy derives from cohort studies with poor or no comparator groups.1,6–14 In patient groups other than those with mechanical heart valves, increasing concerns have surfaced that bridging therapy exposes patients to higher bleeding risks without reducing the risk of thromboembolism.15 Accordingly, decisions about bridging should be individualized and should account for the tradeoffs between thrombosis and bleeding.

Recommendations for Bridging Therapy During Interruption of Oral Anticoagulation in Patients With Prosthetic Heart Valves (Continued)

COR LOE Recommendations

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