Abstract
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a potentially multipathogenic syndrome that affects a subgroup of patients who present with acute myocardial infarction yet have no significant coronary artery disease on angiography. We herein describe a 71-year-old man with typical angina who showed inferior ST-segment elevation on electrocardiography and an increased troponin-I level. Emergency coronary angiography showed no angiographic stenosis. Cardiac magnetic resonance imaging (CMR) and myocardial contrast echocardiography (MCE) with two-dimensional speckle tracking imaging (2D-STI) were performed after coronary angiography. Good consistency was observed between the CMR findings and MCE with 2D-STI findings in identifying the potential causes of MINOCA. We explored an imaging method that is potentially more effective and accurate than CMR, namely MCE combined with 2D-STI, to identify myocardial abnormalities when angiography reveals no obstruction. This application of MCE with 2D-STI may optimize timely treatment. MINOCA has various causes, and the patient in this case was discharged with aspirin, verapamil, and atorvastatin on the presumption that the infarct had arisen from either plaque disruption or coronary spasm. In this study, we analyzed the etiology, clinical diagnosis, and treatment of MINOCA with reference to the relevant literature.