Comment on: Non-vitamin K Antagonist Oral Anticoagulants Versus Warfarin in Patients with Atrial Fibrillation and Liver Disease

Sir,

We read with interest the systemic review and meta-analysis by Fu et al. [1] published in the American Journal of Cardiovascular Drugs. We have the following concerns. From the meta-analysis, the authors concluded that non-vitamin K antagonist oral anticoagulants (NOACs) were associated with a lower risk of all-cause mortality and major bleeding than warfarin in patients with atrial fibrillation and liver disease. However, as interpreted with Higgins I² statistics, these pooled estimates were associated with considerable heterogeneity. This could be because of the difference in the severity of liver disease among included studies. All the currently approved NOACs undergo significant hepatic metabolism, and their use in liver disease is not well-documented. While NOACs can be used in patients with mild to moderate liver disease (Child–Pugh A and B), warfarin is the only recommended oral anticoagulant in patients with severe liver disease (Child–Pugh C) [2]. The authors also concluded that NOACs were noninferior to warfarin in patients with atrial fibrillation and liver disease, but the present meta-analysis did not define a noninferiority margin.