Primary Care Coding Alert

For encounters where the MI is “equal to, or less than, four weeks old” and “the myocardial infarction meets the definition for ‘other diagnoses’”: You should report codes from category I21 (Acute myocardial infarction).

For “encounters after the 4-week time frame and the patient is still receiving care related to the MI”: The “appropriate aftercare code should be assigned, rather than a code from category I21.” In the case of aftercare for an MI, that could mean coding Z51.81 (Encounter for therapeutic drug level monitoring) or Z51.89 (Encounter for other specified aftercare).

For “old or healed myocardial infarctions not requiring further care”: You should assign code I25.2 (Old myocardial infarction).

In other words, if your provider has documented that the patient’s MI is over four weeks old, and if the patient is no longer receiving MI-related care because the MI is now healed, you would code I25.2. This would also be applicable in situations in which a past MI is diagnosed by ECG or other investigation but is currently presenting no symptoms.