en Clinical Medicine Clinical Medicine گزارش موردی Case Report Article <span style="font-size:11pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">Hypereosinophilic syndrome (HES) characterized by persistent eosinophilia without any discernible underlying cause. The patient might exhibit no symptoms at all or may manifest a disorder affecting multiple systems. </span></span></span>&nbsp;<span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:&quot;Times New Roman&quot;,serif">Electrocardiography, echocardiography and cardiac magnetic resonance imaging are commonly used methods to assess cardiac involvement in HES. Recognizing HES early can be difficult since the initial stage typically lacks noticeable clinical symptoms. Here, we report a 45-years-old man with HES which mimics the acute coronary syndrome signs and symptoms, after ruling out other possible diagnoses, Electrocardiography revealed inverted T-waves in pericardial leads (V4&ndash;V6). Coronary angiography demonstrated non-obstructive coronary artery disease. Echocardiography showed moderate left ventricular (LV) hypertrophy, a lobulated apical LV mass, trivial tricuspid regurgitation, and mild pleural effusion. Cardiac MRI identified an apical LV mass with iso/high signal intensity on STIR sequences and no enhancement on late gadolinium enhancement (LGE), consistent with LV thrombus in the setting of HES. On admission, troponin level was 869 ng/ml. HES was confirmed and the patient was treated with prednisolone (5 mg/kg daily) and apixaban (10 mg BID for 7 days, then 5 mg BID). Follow-up demonstrated a decrease in troponin to 351 ng/ml and complete resolution of the LV thrombus on echocardiography.</span></span></span></span></span></span><br> &nbsp; Myocardial Infarction with Non-Obstructive Coronary Arteries, Eosinophil, Hypereosinophilic syndrome. 16 16 http://journal.zums.ac.ir/browse.php?a_code=A-10-7304-1&slc_lang=en&sid=1 Ali Mohammad Haji Zeinali Ali_zeinali_cardio@yahoo.com 5200319475328460088984 5200319475328460088984 No Department of interventional cardiology, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mahzad Bekravi M_bekravi@yahoo.com 5200319475328460088985 5200319475328460088985 Yes Cardiologist, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.