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Updated: May 12, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
[Atrial fibrillation and new oral anticoagulants: a therapeutic revolution?]
Oral anticoagulant therapy (OAT) with vitamin K antagonists significantly reduces thromboembolic risk in patients with atrial fibrillation (AF), but is associated with increased hemorrhagic risk. In older patients, despite a higher hemorrhagic risk, the net clinical benefit is in favor of OAT. In clinical practice, however, underuse of OAT and suboptimal quality control, with unsatisfactory INR time in therapeutic range, are frequently reported. This is particularly true in older patients with AF, despite the fact that they are at higher risk of thromboembolic events. New oral anticoagulants (NOAs) are represented by direct thrombin inhibitors (dabigatran) or direct Xa factor inhibitors (rivaroxaban, apixaban). In phase III studies, NOAs have shown at least a non-inferiority to warfarin in thromboembolic risk reduction in AF patients and are also associated with a reduction in life-threatening bleedings, in particular intracranial bleedings. In addition, NOAs are administered in daily fixed doses and do not require regular INR monitoring. For all these reasons, NOAs will likely replace warfarin in the elderly in the next future.
Oral anticoagulant therapy (OAT) with vitamin K antagonists significantly reduces thromboembolic risk in patients with atrial fibrillation (AF), but is associated with increased hemorrhagic risk. In older patients, despite a higher hemorrhagic risk, the net clinical benefit is in favor of OAT. In clinical practice, however, underuse of OAT and suboptimal quality control, with unsatisfactory INR time in therapeutic range, are frequently reported. This is particularly true in older patients with AF, despite the fact that they are at higher risk of thromboembolic events. New oral anticoagulants (NOAs) are represented by direct thrombin inhibitors (dabigatran) or direct Xa factor inhibitors (rivaroxaban, apixaban). In phase III studies, NOAs have shown at least a non-inferiority to warfarin in thromboembolic risk reduction in AF patients and are also associated with a reduction in life-threatening bleedings, in particular intracranial bleedings. In addition, NOAs are administered in daily fixed doses and do not require regular INR monitoring. For all these reasons, NOAs will likely replace warfarin in the elderly in the next future.
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