From the Guidelines
Anticoagulation in patients with atrial fibrillation and superficial siderosis should generally be avoided due to the high bleeding risk associated with superficial siderosis. For most patients with this combination, alternative approaches such as left atrial appendage closure devices (like Watchman) should be considered to reduce stroke risk without increasing bleeding risk 1. If anticoagulation is deemed absolutely necessary due to very high stroke risk, warfarin with a lower target INR (2.0-2.5) or reduced-dose direct oral anticoagulants (DOACs) like apixaban 2.5mg twice daily may be considered with extremely close monitoring.
Key Considerations
- The risk of thromboembolism from atrial fibrillation must be balanced against the risk of worsening superficial siderosis, which can lead to progressive neurological deterioration including hearing loss, ataxia, and dementia.
- Regular neuroimaging (MRI with hemosiderin-sensitive sequences) every 6-12 months is essential to monitor for progression of siderosis.
- Consultation with both neurology and cardiology specialists is crucial before initiating any anticoagulation therapy.
Management Approach
- According to the 2024 ESC guidelines for the management of atrial fibrillation, oral anticoagulants are recommended for all eligible patients, except those at low risk of incident stroke or thromboembolism 1.
- However, in patients with superficial siderosis, the guidelines' recommendations must be individualized to account for the increased bleeding risk.
- The choice of anticoagulant and dose should be carefully considered, with a preference for reduced-dose DOACs or warfarin with a lower target INR if anticoagulation is necessary.
Ongoing Evaluation
- Periodic reassessment of therapy is crucial to ensure that the benefits of anticoagulation outweigh the risks in patients with atrial fibrillation and superficial siderosis.
- New modifiable risk factors that could slow or reverse the progression of AF, increase quality of life, and prevent adverse outcomes should be identified and addressed 1.
From the Research
Anticoagulation in Atrial Fibrillation with Superficial Siderosis
- Anticoagulation therapy is recommended for preventing stroke in persons with atrial fibrillation 2
- Direct oral anticoagulants (DOACs) are first-line agents for eligible patients for treating venous thromboembolism and preventing stroke in those with nonvalvular atrial fibrillation 2
- The risk of non-major bleeding is lower for apixaban compared to other DOACs and vitamin K antagonists (VKAs) 3
- Apixaban has been shown to have a lower risk of non-major bleeding than other anticoagulants, making it a potential option for patients with atrial fibrillation 3, 4
- In patients with high bleeding risk, the use of low-dose DOAC regimens may not be more appropriate than standard-dose regimens, as they may increase the risk of ischemic stroke and systemic thromboembolism 5
- Superficial siderosis is a potentially manageable neurodegenerative disorder caused by chronic subarachnoid hemorrhage and iron deposition, and its association with oral anticoagulant therapy is well known 6
- Withdrawal of anticoagulation therapy may lead to marked motor and cognitive improvement in patients with superficial siderosis, highlighting the need to consider this modifiable factor in patient management 6
Considerations for Anticoagulation Therapy
- Validated bleeding risk assessments, such as HAS-BLED, should be performed at each visit to identify patients at high risk of bleeding 2
- Modifiable factors, such as the use of anticoagulant therapy, should be addressed to minimize the risk of bleeding 2
- The choice of anticoagulant therapy should be individualized based on the patient's risk factors, including the presence of superficial siderosis 6