1 ︱ INTRODUCTION
Coronary artery anomaly (CAA) is a common cause of sudden cardiac death, a congenital disease of abnormal coronary origin, course, and termination 1. Coronary artery fistula (CAF) is an abnormally terminated CAA with a low prevalence (0.2-0.6%) and is usually detected incidentally during the diagnostic examination for ischemic heart diseases 2. Ischemic symptoms of CAF are caused by coronary steal where coronary blood flows into low-pressure areas of the fistula (eg, right ventricle, right atrium, pulmonary artery, or coronary sinus), resulting in distal myocardium ischemia. The latest data show that CAF accounts for 0.32% of total coronary anomalies in Southwest China as determined by angiography3. Especially, a giant left coronary artery aneurysm that fistula to the right atrium and accompanied by ruptured aortic sinus aneurysm (RASA) is rarely reported. Notably, even asymptomatic coronary fistulas can lead to severe complications, such as endocarditis, coronary aneurysms, myocardial infarction, or cardiac arrest; therefore, catheter-based closure or surgical therapy is often required.