ICD-10-CM > I00-I99 > I20-I25 > I21 > I21.0 I21.0 ST elevation (STEMI) myocardial infarction of anterior wall Non-Billable/Non-Specific Applicable To Type 1 ST elevation myocardial infarction of anterior wall Codes I21.01ST elevation (STEMI) myocardial infarction involving left main coronary arteryI21.02ST elevation (STEMI) myocardial infarction involving left anterior descending coronary arteryI21.09ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wall