Unexpectedly large thrombi in the left atrium detected with intracardiac echocardiography in a case after left atrial appendage ligation

The incidence of atrial fibrillation (AF) is gradually increasing because of the aging society.1 Various methods for preventing cerebral embolisms, including anticoagulants, percutaneous left atrial appendage (LAA) closure, surgical LAA ligation, and surgical LAA resection, have been widely performed.2 Surgical LAA exclusion is an excellent treatment that effectively reduces the incidence of strokes. Therefore, it is increasingly performed during mitral valve surgery and surgical pulmonary vein isolation.