ICD-10-CM > I00-I99 > I20-I25 > I23 > I23.1 I23.1 Atrial septal defect as current complication following acute myocardial infarction Billable/Specific Copy Code Copy Description Type 1 Excludes acquired atrial septal defect not specified as current complication following acute myocardial infarction (I51.0)