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Updated: Jul 2, 2025

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Current Gaps in the Provision of Safe and Effective Anticoagulation in Atrial Fibrillation and the Potential for
Shaun G Goodman1,2, Denis Roy3, Charles V Pollack4
1From the Division of Cardiology, St Michael's Hospital, Peter Munk Cardiac Centre, University Health Network, University of Toronto, Toronto, ON, Canada.
Insights
Stroke prevention in atrial fibrillation is suboptimal due to underprescribing and poor adherence to anticoagulation. New factor XI-directed anticoagulants may offer improved safety and efficacy for patients.
Area of Science:
- Cardiology
- Hematology
- Pharmacology
Background:
- Global atrial fibrillation (AF) prevalence is rising, increasing stroke risk.
- Anticoagulation therapy reduces stroke risk in AF but is underutilized and suboptimal.
- Advances in anticoagulants (e.g., DOACs) improved safety but population-level stroke protection remains poor.
Purpose of the Study:
- To address gaps in anticoagulation therapy for stroke prevention in AF.
- To discuss challenges in current anticoagulation management.
- To explore the potential of factor XI-directed anticoagulants for improved stroke prevention.
Main Methods:
- A multidisciplinary panel convened at the 2023 International Society of Thrombosis and Haemostasis Congress.
- Discussion focused on recognizing and addressing therapeutic gaps.
- Reevaluation of coagulation cascade principles was proposed.
Main Results:
- Current anticoagulation for AF stroke prevention faces multifactorial deficits.
- Underprescribing, drug limitations, and poor patient adherence contribute to suboptimal outcomes.
- Factor XI-directed anticoagulants present a potential advancement.
Conclusions:
- Optimizing stroke prevention in AF requires addressing prescribing and adherence barriers.
- Understanding hemostasis and thrombosis separately is crucial.
- Factor XI inhibitors may offer a safer and more effective anticoagulation strategy.
Abstract:
The global prevalence of atrial fibrillation is rapidly increasing, in large part due to the aging of the population. Atrial fibrillation is known to increase the risk of thromboembolic stroke by 5 times, but it has been evident for decades that well-managed anticoagulation therapy can greatly attenuate this risk. Despite advances in pharmacology (such as the shift from vitamin K antagonists to direct oral anticoagulants) that have increased the safety and convenience of chronic oral anticoagulation in atrial fibrillation, a preponderance of recent observational data indicates that protection from stroke is poorly achieved on a population basis. This outcomes deficit is multifactorial in origin, stemming from a combination of underprescribing of anticoagulants (often as a result of bleeding concerns by prescribers), limitations of the drugs themselves (drug-drug interactions, bioaccumulation in renal insufficiency, short half-lives that result in lapses in therapeutic effect, etc), and suboptimal patient adherence that results from lack of understanding/education, polypharmacy, fear of bleeding, forgetfulness, and socioeconomic barriers, among other obstacles. Often this adherence is not reported to treating clinicians, further subverting efforts to optimize care. A multidisciplinary, interprofessional panel of clinicians met during the 2023 International Society of Thrombosis and Haemostasis Congress to discuss these gaps in therapy, how they can be more readily recognized, and the potential for factor XI-directed anticoagulants to improve the safety and efficacy of stroke prevention. A full appreciation of this potential requires a reevaluation of traditional teaching about the "coagulation cascade" and decoupling the processes that result in (physiologic) hemostasis and (pathologic) thrombosis. The panel discussion is summarized and presented here.
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