Acute left main coronary artery thrombosis as an initial presentation of systemic lupus erythematosus.

Left main coronary artery (LMCA) thrombosis is rare and the cause should be determined. A previously healthy young man presented with severe chest pain and dyspnea. The electrocardiogram showed typical ST-segment elevation myocardial infarction with clinical instability. Emergency coronary angiography revealed complete LMCA occlusion by thrombosis. After reperfusion, the patient was admitted to the cardiac care unit. He was diagnosed with hemolytic anemia and tested positive for antinuclear antibodies. Systemic lupus erythematosus (SLE) and LMCA disease due to systemic thrombosis were diagnosed. Steroids were started and the patient was discharged without complications. We report this rare case of LMCA thrombosis as an initial presentation of SLE.