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Updated: Aug 12, 2026

23:33
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
[Atrial fibrillation--thromboembolism and prevention]
P Petersen1, G Boysen, J Godtfredsen
1Rigshospitalet, København, neuromedicinsk afdeling.
Ugeskrift for Laeger
|July 22, 1991
Summary
Atrial fibrillation increases stroke risk, especially in those with prior heart attacks. Warfarin effectively reduces thromboembolic events, while aspirin
Area of Science:
- Cardiology
- Neurology
- Pharmacology
Context:
- Chronic non-rheumatic atrial fibrillation (AF) carries a significant annual risk of thromboembolic complications (approx. 5%).
- Previous myocardial infarction is a key risk factor for thromboembolism in AF patients.
- Silent cerebral infarction is more prevalent in chronic AF patients compared to those in sinus rhythm.
Purpose:
- To evaluate the efficacy of anticoagulation therapies, specifically warfarin and aspirin, in preventing thromboembolic complications in patients with atrial fibrillation.
- To assess the influence of patient demographics, such as age and history of myocardial infarction, on treatment outcomes.
Summary:
- Warfarin demonstrated effectiveness in reducing thromboembolic complications across three prospective trials.
- Aspirin (325 mg daily) showed efficacy only in patients under 75 years old; its effect was not observed in older patients or in other trials.
- Paroxysmal and isolated AF in younger individuals may present a lower embolic risk.
Impact:
- Provides evidence-based guidance on anticoagulation strategies for atrial fibrillation management.
- Highlights the importance of risk stratification, considering factors like age and prior myocardial infarction, when selecting therapy.
- Informs clinical decision-making regarding stroke prevention in diverse atrial fibrillation patient populations.
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