How to Avoid Adverse Events During Apixaban Therapy in Patients With Atrial Fibrillation

When Should We Measure Anti-Xa Activity? Fixed-dosage apixaban therapy significantly reduces adverse bleeding events compared with adjusted-dosage warfarin with PT monitoring. 1 However, still possible that adverse events under apixaban may occur in AF patients with a high risk of bleeding. To reduce bleeding it might be sonable to monitor apixaban plasma concentration in such circumstances. Baglin et al reported that the following situations may be appropriate for monitoring anti-Xa activity: bleeding incidents, perioperative management, and suspicion of overdose because of worsening of renal function. In addition, patients' non-adherence to anticoagulant NOAC therapy is associated with thromboembolic events. When the thrombotic event occurs, measuring anti-Xa activity may be useful to monitor whether patients are regularly taking NOACs. The cost of measuring anti-Xa activity is another issue to be solved in the future, because it is not covered by insurance.