Science and Education Publishing American Journal of Medical Case Reports 2374-216X 3 2 2015 01 23 Unexpected Acute Myocardial Infarction Due to Disseminated Intravascular Coagulation 42 45 EN Motoharu Shibusawa Department of Hematology Medicine, Tokyo Metropolitan Health and Medical Treatment Corporation, Tama-Hokubu Medical Center, Tokyo, Japan Takaaki Matsumura Hisashi Tsutsumi Yuuji Itou Yoshiaki Shibata AJMCR2015327 10.12691/ajmcr-3-2-7 2014 12 02 2015 01 20 2015 01 23 An autopsy case of gastric cancer accompanied by disseminated intravascular coagulation (DIC) that resulted in unexpected acute myocardial infarction (AMI) is reported. A 66-year-old man was introduced to our hospital and was diagnosed with gastric cancer accompanied by bone marrow carcinomatosis with DIC. On the fourteenth day of admission, he experienced dyspnea. He died on the fifteenth day. An autopsy was performed. The autopsy findings revealed myocardial infarction from the lateral to anterior and posterior ventricular walls, thromboembolism in the right coronary artery, and nonbacterial thrombogenic carditis of the mitral valve. A diagnosis of AMI was made by the autopsy findings. In cases accompanied by DIC, thrombus may develop in coronary arteries, resulting in AMI. In these patients, the typical symptoms of AMI and ST-segment elevation and pathologic Q waves on electrocardiogram are often not observed. The importance of this phenomenon warrants consideration in clinical practice.