A rare coronary anomaly detected during primary percutaneous coronary angioplasty: totally occluded left main coronary artery originating from the right coronary artery

Left main coronary artery originating from the right coronary artery (RCA) is a rare anomaly. A 52-year-old male patient was submitted to catheterization laboratory for primary percutaneous coronary angioplasty with a diagnosis of acute anterior myocardial infarction. He had several risk factors including smoking, hypertension, and type 2 diabetes mellitus. Selective right coronary angiography showed an eccentric 85% stenosis at the mid-segment of the RCA, and the left main coronary artery originating from the right aortic sinus. The proximal segment of the left main coronary artery was completely occluded with thrombus and there was severe stenosis (95%) at the bifurcation of the left anterior descending artery with the circumflex artery. A metal stent was implanted in the stenotic segment of the left main coronary artery. The patient was discharged on the seventh day of stent implantation without any complications. Coronary artery bypass grafting was planned for stenotic lesions in the RCA and at the bifurcation of the left anterior descending artery with the circumflex artery.