Essential thrombocythemia presenting as acute coronary syndrome: case reports and literature review.

For the patients with essential thrombocythemia (ET), systemic thrombosis presents as one of the most dangerous complications. It's been widely accepted that acute coronary syndrome (ACS) is a kind of thrombotic diseases. However, there are very few case reports about ET first presenting as ACS. For some patients diagnosed as ACS, but without markedly elevated platelet, underlying ET was missed. And there are some controversies in the principles and target of treatment in those patients. We reported three cases of ACS, in which the patients who did not have common risk factors for coronary artery diseases and presented only mild atherosclerotic stenosis during coronary angiography, one of which had recurrent coronary artery thrombosis. Noticing their elevated blood platelet level and characteristics in angiography, diagnosis of ET was made according to bone marrow morphology and genetic tests. Although they had only mild thrombocytosis, we applied intensive treatment with dual anti-platelet therapy combined with cytoreduction in addition to early coronary intervention, having satisfying outcomes. During the diagnosis and treatment of ACS, if patients present thrombocytosis, but lack common coronary disease risk factors and thrombotic coronary artery occlusion, cardiologists should search for possible ET as an underlying cause of thrombotic coronary event. All those patients were high-risk according to ET risk stratification. Treatment of cytoreduction in combination with anti-thrombosis therapy and revascularization are beneficial. Treatment aims at the target of complete response with platelet count below 400 × 10