Large Thrombus Originating From Left Atrial Diverticulum

Abstract

A 45-year-old man was admitted to our hospital for evaluation of a left atrial (LA) mass. The patient had a history of dilated hypertrophic cardiomyopathy, atrial fibrillation (AF), diabetes mellitus, and sustained ventricular tachycardia that was treated by implantation of a cardioverter-defibrillator. He had developed AF 1 year earlier and was followed up at the outpatient clinic. He had been treated with warfarin at a dose that resulted in an international normalized ratio of 2.0 to 3.0. The LA mass was detected incidentally on routine transthoracic echocardiography. He was referred to our hospital because the size of the LA mass was unchanged after intensive anticoagulation with intravenous heparin infusion. The mobile LA mass along the interatrial septum was detected by transthoracic echocardiography in the apical 4-chamber view (Figure 1 and Movie I in the online-only Data Supplement). Transesophageal echocardiography showed a huge mobile mass (2.6×1.4 cm) originating from the roof of the LA (Figure 2A and Movie II in the online-only …