Ectasia of the left atrial appendage is a rare cardiac malformation characterized by the enlargement of the left auricle without any other associated cardiac lesions. It can be asymptomatic (discovered fortuitously during routine chest imaging as an unusual cardiac shadow) or present clinically with supraventricular tachyarrhythmia, paroxysmal tachycardia, embolic events, respiratory distress, chest pain, angina pectoris or heart failure.