Extracardiac Adipose Tissue Mimicking an Intracavitary Left Atrial Mass on Echocardiography

skeletal muscle mass, 35.1 kg; body fat mass: 33.5 kg).Liver function tests were mildly abnormal.TTE revealed a highly echogenic mass measuring 23.9×19.6×35.5 mm in the left atrium (LA), adjacent to the aortic valve (Figure A,B; Supplementary Movie).Contrast-enhanced cardiac computed A n 18-year-old female competitive throwing athlete was referred for an incidental mass detected on transthoracic echocardiography (TTE) during a preparticipation medical checkup.She was asymptomatic with a body mass index of 33.5 kg/m 2 (body weight, 94.2 kg;