Unstable angina and old myocardial infarction in a patient with thrombocythemia

Essential thrombocythemia is a kind of myeloproliferative disorder characterized by primary elevation in the number of platelet and by multiple episodes of bleeding or thrombotic complications. Rarely, thrombocythemia itself causes coronary arterial occlusion and leads to ischemic heart disease. Fewer than twenty cases of coronary artery occlusive disease in thrombocythemia have been reported since Cheitlin et al had included thrombocythemia in their review of rare causes of myocardial infarction. We experienced a case of coronary artery disease in a 53-year-old woman with thrombocythemia, who had not coronary artery disese risk factors at all. Presence of multiple thrombus in the coronary artery was suggested in coronary angiography.