Totally Occluded Grafted Right Internal Mammary Artery to Anomalously Originated Right Coronary Artery

An anomalous aortic origin of a coronary artery is rare and surgical intervention is recommended when the patient is symptomatic. We performed coronary artery bypass graft surgery in a 21-year-old male patient with a right coronary artery anomalously originating from the left coronary sinus. The artery was significantly stenosed by external compression between the aorta and the pulmonary artery. However, the graft became occluded 1 year after the operation. In such cases, the dynamic nature of the stenosis can cause relatively intact antegrade competitive flow from the native coronary artery and lead to an occlusion of the grafted artery. Methods for evaluating flow rates or intraluminal pressures of native arteries could be helpful in decision-making in similar cases.