From the Guidelines
Mitral Valve Replacement (MVR) with a mechanical valve typically requires lifelong anticoagulation with a Vitamin K Antagonist (VKA) to achieve an INR of 3.0, as recommended by the 2017 AHA/ACC guideline 1. The need for anticoagulation in patients with MVR depends on the type of valve used, with mechanical valves requiring lifelong anticoagulation and bioprosthetic valves potentially requiring short-term anticoagulation.
- For mechanical MVR, anticoagulation with a VKA is indicated to achieve an INR of 3.0, as stated in the 2017 AHA/ACC guideline 1.
- For bioprosthetic MVR, anticoagulation with a VKA to achieve an INR of 2.5 is reasonable for at least 3 months and for as long as 6 months after surgery in patients at low risk of bleeding, as recommended by the 2021 guideline for the prevention of stroke 1. Key considerations in determining the need for anticoagulation include the type of valve used, the patient's risk of bleeding, and their individual risk factors for thromboembolic events.
- Aspirin 75 mg to 100 mg daily is recommended in addition to anticoagulation with a VKA in patients with a mechanical valve prosthesis 1.
- The potential benefit of anticoagulation therapy must be weighed against the risk of bleeding, and patients should be closely monitored for signs of bleeding or thromboembolic events. In general, the decision to use anticoagulation in patients with MVR should be individualized based on the patient's specific risk factors and medical history, with a focus on minimizing the risk of morbidity, mortality, and reducing the impact on quality of life 1.
From the FDA Drug Label
For all patients with mechanical prosthetic heart valves, warfarin is recommended. For patients with tilting disk valves and bileaflet mechanical valves in the mitral position, the 7th ACCP recommends a target INR of 3.0 (range, 2.5 to 3.5).
Mitral Valve Replacement (MVR) with a mechanical valve requires anticoagulation with warfarin, targeting an INR of 2.5-3.5, depending on the valve type. 2
From the Research
Mitral Valve Replacement and Anticoagulation
The need for anticoagulation after Mitral Valve Replacement (MVR) is a topic of ongoing debate. Several studies have investigated the role of anticoagulation in patients undergoing MVR.
Studies on Anticoagulation after MVR
- A study published in 2020 3 found that postoperative warfarin use was associated with a reduced composite of bleeding and thromboembolic complications and superior long-term survival in patients undergoing mitral valve repair.
- Another study published in 2013 4 found that mitral valve repair and bioprosthetic replacement without postoperative anticoagulation did not increase the risk of stroke or mortality.
- A study published in 2006 5 concluded that short-term anticoagulation may be necessary after mitral valve repair, citing the absence of studies supporting the safety of omitting warfarin.
- A study published in 2018 6 found that vitamin K antagonists (VKA) and aspirin had similar event rates of thromboembolic and bleeding complications in patients undergoing mitral valve repair.
- A study published in 2020 7 found that rivaroxaban was safe and efficient in patients undergoing surgical mitral valve repair, with no major bleeding or cerebrovascular accidents occurring during the 1-year follow-up.
Key Findings
- The use of anticoagulation after MVR may reduce the risk of thromboembolic complications and improve long-term survival 3.
- The type of anticoagulation used (e.g. warfarin, VKA, aspirin, rivaroxaban) may not significantly impact the risk of thromboembolic or bleeding complications 4, 6, 7.
- The duration of anticoagulation after MVR is unclear, with some studies suggesting short-term anticoagulation may be sufficient 5 while others recommend longer-term anticoagulation 3.