Related Experiment Video
Updated: Mar 31, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Add-on antiplatelet therapy in anticoagulated patients with atrial fibrillation
Yuki Matsuoka1, Hitoshi Minamiguchi2, Daisuke Sakamoto1
1Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
Insights
Adding antiplatelet therapy to oral anticoagulants in atrial fibrillation patients increases risks for both ischemic and bleeding events. This real-world study highlights potential dangers of combined therapies outside specific post-procedure windows.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Research
Background:
- Atrial fibrillation (AF) management often involves oral anticoagulants (OAC).
- The role of add-on antiplatelet therapy (APT) in non-valvular AF patients on OAC in real-world practice is not well-defined.
- Investigating the clinical impact of APT in this patient population is crucial for optimizing treatment strategies.
Purpose of the Study:
- To evaluate the clinical impact of add-on antiplatelet therapy in patients with non-valvular atrial fibrillation (AF) treated with oral anticoagulants (OAC).
- To assess the risks of ischemic and bleeding events associated with combined OAC and APT versus OAC alone in a real-world setting.
Main Methods:
- Pooled analysis of three large-scale real-world datasets (DIRECT-Extend registry).
- Inclusion of non-valvular AF patients treated with OAC, excluding those within 1 year post-PCI/CABG.
- Utilized inverse-probability-of-treatment weighting (IPTW) to compare outcomes between OAC alone and OAC + APT groups.
Main Results:
- A total of 7387 patients were analyzed (OAC alone: 6096; OAC + APT: 1291).
- The OAC + APT group showed a significantly higher risk for the primary ischemic endpoint (wHR: 1.28; p < 0.001).
- The OAC + APT group also had a significantly higher risk for the primary bleeding endpoint (wHR: 1.26; p < 0.001).
Conclusions:
- In real-world practice, add-on antiplatelet therapy in AF patients on OAC is associated with increased risks of both ischemic and bleeding events.
- These findings suggest caution when prescribing combined therapies outside of acute coronary syndromes or recent procedures.
- The results may not be generalizable to patients in the early post-percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) periods.
Background:
The impact of add-on antiplatelet therapy in patients with atrial fibrillation (AF) on oral anticoagulants (OAC) in real-world clinical practice remains to be investigated.
Methods:
We conducted DIRECT-Extend registry, a pooled analysis combining three large-scale real-world datasets of non-valvular AF patients treated with anticoagulation. We assessed clinical impacts of the add-on antiplatelet therapy using the inverse-probability-of-treatment weighting methods. Antiplatelet therapy included aspirin, P2Y12 inhibitors, and cilostazol (dual therapy included). The primary ischemic endpoint was a composite of all-cause death, ischemic stroke, systemic embolism, and myocardial infarction. The primary bleeding endpoint was any bleeding, defined as a composite of major bleeding and clinically relevant non-major bleeding according to the criteria of the International Society on Thrombosis and Hemostasis.
Results:
A total 7387 eligible patients (excluding those within 1 year after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG)) were divided into two groups: the OAC alone group (N = 6096) and the OAC + APT group (treated with both OAC and antiplatelet therapy, N = 1291). The median follow-up period was 1012 [404, 1344] days. The risk for both the primary ischemic and bleeding endpoint was higher in patients in OAC + APT group than those in OAC alone group (ischemic endpoint, weighted hazard ratio (wHR): 1.28, 95%CI [1.17 - 1.40], p < 0.001; bleeding endpoint, wHR: 1.26 [1.19-1.33], p < 0.001).
Conclusion:
The large-scale real-world data demonstrated that, in AF patients treated with OAC, add-on antiplatelet therapy was associated with a higher risk for both ischemic and bleeding endpoints. These findings may not be generalizable to the early post-PCI/CABG period.
Related Concept Videos
Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors
Prostaglandin synthesis inhibitors, exemplified by the widely known aspirin, wield their power by irreversibly acetylating...
Venous Thrombosis III: Interprofessional Care
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
Peripheral Artery Disease III: Interprofessional Care
Coronary Artery Disease V: Interprofessional Care

