[A case of myocardial infarction in a young man with systemic lupus erythematosus].

Apparently the incidence of coronary artery disease in systemic lupus erythematosus (SLE) has been increasing. However, most of the cases had been treated with corticosteroids, and had atherosclerotic lesions in the coronary arterial tree. A 21-year-old man with latent and untreated SLE had an attack of acute myocardial infarction. Coronary arteriography showed eccentric stenotic lesion at the proximal segment of the right coronary artery. One week later, in the 2nd coronary arteriography, this stenotic lesion was not able to be recognized. We supposed that the coronary artery occlusion was due to thrombus formation, and was not related to atherosclerosis, arteritis and embolus. He had no coronary risk factors. Laboratory data showed lymphocytopenia, proteinuria, positive antinuclear antibody, and positive LE cell, and the case was diagnosed as SLE. Subsequent investigations showed the presence of antibodies to cardiolipin. It was suggested that anticardiolipin antibody and other thrombogenic factors were the causes of the coronary occlusive thrombosis in this patient with SLE.