The article discusses myocardial infarction (MI) under the International Classification of Diseases, 10th Revision, Clinical Modification or ICD-10-CM. Topics discussed include separate categories for ST elevation MI (STEMI) in different areas of the heart, a portable chest X-ray for a patient in the coronary care unit as an example of code assignment for acute MI, and codes from ICD-10-CM for subsequent STEMI taking place within a month of the initial MI.