Our cardiologists have stated that if type 2 myocardial infarction (T2MI) is documented, it should be coded to a non-ST elevation myocardial infarction (NSTEMI). We are trying to minimize the number of queries regarding these type of MI’s and would like Coding Clinic’s advice regarding this statement.
Assign code I21.4, Non-ST elevation (NSTEMI) myocardial infarction, for a T2MI. Typically, a type 2 myocardial infarction is marked by non-ST elevation, and occurs secondary to cardiac stress due to other causes (i.e., ischemia resulting from a supply-and-demand mismatch), without atherosclerotic plaque rupture, but with myocardial necrosis. Therefore, code a type 2 myocardial infarction as a NSTEMI, unless otherwise documented as STEMI.Myocardial infarctions that show an ST segment change on electrocardiogram (ECG) are referred to as ST elevation myocardial infarctions (STEMI), and generally involve the whole thickness of myocardium from epicardium to endocardium. Myocardial infarctions that do not show an ST segment change on ECG are referred to as non-ST elevation myocardial infarctions (NSTEMI), and generally do not involve the whole thickness of myocardium.