Non-vitamin K oral antagonist failure and tailored treatment in patients with atrial fibrillation and stroke

Abstract

In case of any embolic event, treatment strategy should be established according to the pathomechanisms of failure of non-vitamin K oral anticoagulants (NOAC). A 72-year-old man was referred to our hospital with a sudden speech disturbance. Diffusion-weighted imaging revealed cerebral infarction in the left middle cerebral artery territory. The patient had been diagnosed with nonvalvular atrial fibrillation 3 years ago and was administered a dose of 60 mg edoxaban/day. Anti-Xa and factor Xa activity assay confirmed the effect of this drug. A detailed transthoracic and transesophageal echocardiography revealed fibroelastoma of mitral valve, atrial septal defect, and spontaneous echo contrast in the left atrial appendage. Although the drug was effective, cardioembolism occurred and hence we decided to perform surgery. As the etiology of NOAC failure varies, anti-Xa and factor Xa activity assays help to determine the cause modifying the treatment strategy accordingly.