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Updated: May 22, 2026
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
[Prevention of thromboembolism in atrial fibrillation]
1Serviço de Cardiologia, Hospital de Santa Cruz, CHLO, Carnaxide, Portugal. ctaguiar@sapo.pt
Insights
Atrial fibrillation (AF) increases stroke risk, especially with age. New oral anticoagulants offer safer, easier stroke prevention compared to older drugs, improving patient outcomes.
Area of Science:
- Cardiology
- Vascular Medicine
- Pharmacology
Context:
- Atrial fibrillation (AF) is the most common chronic heart rhythm disorder.
- AF significantly elevates the risk of thromboembolic events, particularly ischemic stroke.
- Stroke risk in AF patients increases substantially with advancing age.
Purpose:
- To review the role of thromboembolic risk stratification in atrial fibrillation management.
- To evaluate the efficacy and safety of anticoagulation strategies for stroke prevention in AF.
- To compare traditional vitamin K antagonists with newer oral anticoagulants.
Summary:
- Oral anticoagulation is crucial for preventing stroke in nonvalvular AF but is often underutilized or sub-therapeutic with vitamin K antagonists.
- Newer oral anticoagulants (NOACs), including direct thrombin and factor Xa inhibitors, demonstrate comparable efficacy to warfarin.
- NOACs offer improved safety profiles, notably a significant reduction in intracranial bleeding, a major cause of warfarin-related mortality.
Impact:
- Wider adoption of NOACs has the potential to increase the rate of adequate anticoagulation in AF patients.
- Improved anticoagulation management can significantly reduce the incidence of AF-related strokes.
- Enhanced stroke prevention in AF represents a major clinical advancement in cardiovascular medicine.
Abstract:
Atrial fibrillation (AF) is the most prevalent chronic arrhythmia in the general population. The prognosis of AF is mainly marked by the associated thromboembolic phenomena. Of every six ischemic strokes, one is due to AF, but the proportion of ischemic strokes attributable to AF increases with age. Thromboembolic risk stratification is a key component of the clinical evaluation of the AF patient, and a clinical performance measure, and should guide the antithrombotic therapeutic strategy. Oral anticoagulation with vitamin K antagonists is effective for the prevention of ischemic stroke in nonvalvular AF but, due to several reasons, it is largely underutilized in daily clinical practice, and INR values are often sub-therapeutic. The new oral anticoagulants (thrombin inhibitors or factor Xa inhibitors) are easier to manage, and don't require laboratorial monitoring. In phase III clinical trials they have shown to be at least as effective as warfarin, but safer, particularly regarding intracranial bleeding, a complication that is responsible for 90% of warfarin-attributable deaths. These results show a potential to increase the proportion of AF patients adequately anticoagulated, which will represent a significant advance in the prevention of stroke attributable to AF.
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