A patient with a recent non-ST elevated myocardial infarction (NSTEMI) was diagnosed with a myocardial rupture in the basilar wall. The myocardial rupture was diagnosed outside the 28-day post myocardial infarction (MI) period. Per coding guidelines, a code from category I22 must be used when a patient has a new acute myocardial infarction (AMI) within 4 weeks of an initial AMI. How is a myocardial rupture coded, when the condition was diagnosed outside of the 28-day period?
Assign code I23.3, Rupture of cardiac wall without hemopericardium as current complication following acute myocardial infarction. Code I23.3 indicates the patient had a previous MI; therefore, an additional code is not assigned for the previous NSTEMI. The term “within the 28-day period” is a non-essential modifier at category I23, Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction, that may be present or absent in the statement of the disease, and does not affect code assignment.