From the Guidelines
Bioprosthetic aortic valves typically do not require long-term anticoagulation therapy, but may require a short course of anticoagulation with warfarin for the first 3 months post-surgery, after which aspirin alone is usually sufficient. The decision to use anticoagulation therapy in patients with bioprosthetic aortic valves is based on the individual patient's risk of bleeding and thromboembolism. According to the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack, oral anticoagulation with warfarin to achieve a target INR of 2.5 (range, 2.0–3.0) is reasonable for at least 3 months and for as long as 6 months after surgery in patients at low risk of bleeding 1.
After 3 to 6 months after surgery, long-term therapy with only aspirin 75 to 100 mg daily is recommended 1. The 2020 ACC/AHA guideline for the management of patients with valvular heart disease also suggests that initial 3-6 months of anticoagulation with warfarin or dual antiplatelet therapy may be considered in patients with bioprosthetic aortic valves, but the risk of thromboembolism is approximately 0.7% per year in patients with biological valves in sinus rhythm 1.
Key points to consider when deciding on anticoagulation therapy for patients with bioprosthetic aortic valves include:
- The patient's risk of bleeding and thromboembolism
- The type of valve used (bioprosthetic vs mechanical)
- The presence of additional risk factors for thromboembolism (such as atrial fibrillation, left ventricular dysfunction, previous thromboembolism, or hypercoagulable states)
- The patient's ability to tolerate long-term anticoagulation therapy.
Regular follow-up with a cardiologist is essential to monitor valve function and adjust anticoagulation therapy as needed.
From the FDA Drug Label
For patients with bioprosthetic valves, warfarin therapy with a target INR of 2.5 (range, 2.0 to 3.0) is recommended for valves in the mitral position and is suggested for valves in the aortic position for the first 3 months after valve insertion. The bioprosthetic aortic valve may need anticoagulant therapy with warfarin for the first 3 months after valve insertion, but it is only suggested, not explicitly recommended.
- The target INR for this therapy is 2.5 (range, 2.0 to 3.0) 2.
From the Research
Anticoagulation Therapy for Bioprosthetic Aortic Valve
- The need for anticoagulant therapy after bioprosthetic aortic valve replacement is a topic of ongoing debate 3, 4, 5.
- Most studies suggest that anticoagulation is not necessary for patients at low risk of thromboembolism, and that antiplatelet therapy may be sufficient 3, 4.
- However, some studies recommend anticoagulation for certain patient populations, such as those with a history of stroke or atrial fibrillation 6, 7.
- The use of novel oral anticoagulants (NOACs) has been shown to be effective and safe in patients with bioprosthetic aortic valves and atrial fibrillation 7.
- The choice of antithrombotic therapy after bioprosthetic aortic valve replacement should be individualized based on the patient's risk factors and medical history 3, 5.
Risks and Benefits of Anticoagulation Therapy
- Anticoagulation therapy can increase the risk of bleeding complications, particularly in the early postoperative period 4.
- However, anticoagulation therapy can also reduce the risk of thromboembolic events, such as stroke and valve thrombosis 6, 7.
- The benefits and risks of anticoagulation therapy should be carefully weighed in each patient, taking into account their individual risk factors and medical history 3, 5.
Current Guidelines and Recommendations
- Current guidelines recommend antiplatelet therapy for all bioprosthetic valve replacements, with anticoagulation recommended for patients with a history of stroke or atrial fibrillation 6.
- However, the optimal antithrombotic strategy after bioprosthetic aortic valve replacement remains unclear, and further studies are needed to inform clinical practice 3, 5.