The CHA2DS2-VASc is a clinical score used in everyday clinical practice to evaluate thrombo-embolic risk in patients with atrial fibrillation (AF) [1], and the guidelines for the management of AF subjects give recommendations on oral anticoagulant therapy based on this score [2]. Many studies have reported correlations between the CHA2DS2-VASc and several important outcomes in AF patients, such as bleeding [3] and pulmonary embolism [4]. Also, the complications of thrombo-embolic stroke [5] and reduced glomerular filtration rate [6] are related to the CHA2DS2-VASc score.