The International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code group I22 includes subsequent ST elevation myocardial infarction and subsequent non-ST elevation myocardial infarction, representing acute myocardial infarctions that occur after a prior confirmed acute myocardial infarction. These ICD-10-CM diagnosis codes are used to document recurrent or subsequent infarctions, capturing timing relative to a prior event and the type of myocardial injury. Accurate coding within the ICD-10-CM I22 group supports proper claim adjudication and complete clinical documentation for appropriate reimbursement.