Abstract
Essential thrombocythemia (ET) is a clonal disorder of myeloid stem cells that causes thrombocytosis. As a result, ET can lead to vascular thrombosis and tissue ischemia; the association of coronary artery abnormalities such as myocardial infarction or unstable angina is rare. Here we describe a 45,-year-old male patient with essential thrombocythemia who presented with unstable angina. Elective coronary angiography showed total occlusion of mid right coronary artery and mid left anterior descending coronary artery. ET was confirmed by a bone marrow biopsy; treatment was started with antiplatelet therapy including aspirin and clopidogrel along with cytostatic therapy with hydroxyurea and anagrelide. After the initiation of the treatment, the platelet count decreased to 20 x 10(4)/microL. In addition, percutaneous coronary angioplasty was successfully performed with stent placement at the right coronary artery without hemorrhagic or thrombotic complications.