Old myocardial infarction

This code signifies a myocardial infarction (heart attack) that occurred in the past and is no longer in its acute phase. It indicates the presence of myocardial damage or scarring resulting from a prior ischemic event, without evidence of current myocardial necrosis. The patient is stable, and the acute symptoms have resolved.

Use this code when documentation clearly states "old myocardial infarction," "healed myocardial infarction," or "history of myocardial infarction" with residual cardiac damage. This diagnosis is appropriate when the patient is seen for follow-up care, management of sequelae, or for conditions unrelated to the acute event but where the old MI is a relevant comorbidity. Documentation must confirm the MI is not acute.

• Do not use this code for an acute myocardial infarction; refer to the I21.x series for acute events.
• Ensure the documentation specifies "old" or "healed" MI; a simple "history of MI" without further clarification may require physician query.
• This code is often sequenced as a secondary diagnosis when the patient is being treated for other conditions, but the old MI impacts treatment or prognosis.