Health Sciences Center, Denver, Colorado.

The use of anticoagulation therapy for atrial fibrillation has slowly increased in the last decade, yet many patients at relatively high risk for thromboembolic events are still not receiving anticoagulants. Patients receiving therapy that is intended to maintain sinus rhythm may be at higher risk for underuse of anticoagulation therapy than those receiving rate control therapies. In addition, the increase in the use of anticoagulation therapy appears to have been particularly notable among patients for whom it may not be indicated and in whom safer, less expensive antithrombotic therapies would suffice.