MCMCB Pro
I21.02

I21.02ST elevation (STEMI) myocardial infarction involving left anterior descending coronary artery

Billable / specific codeICD-10-CMleft

I21.02 is a billable, specific ICD-10-CM code for st elevation (stemi) myocardial infarction involving left anterior descending coronary artery. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • ST elevation (STEMI) myocardial infarction involving diagonal coronary artery

Risk adjustment

I21.02 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

  • HCC 228 Acute Myocardial Infarction0.252 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.

Medicare coverage

I21.02 is named in 64 Medicare coverage policies 64 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A52458Automatic External Defibrillators - Policy Article
  • A52458Automatic External Defibrillators - Policy Article
  • A52850Billing and Coding: Cardiac Catheterization and Coronary Angiography
  • A52850Billing and Coding: Cardiac Catheterization and Coronary Angiography

How I21.02 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to I21.02.

  • Infarct, infarctionmyocardium, myocardialST elevationinvolvingdiagonal coronary artery
  • Infarct, infarctionmyocardium, myocardialST elevationinvolvingleft anterior descending coronary artery

Related codes at this level

Codes that share I21.0. If I21.02 is not quite right, the correct code is usually one of these.

Questions about I21.02

Is I21.02 a billable ICD-10-CM code?
Yes. I21.02 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does I21.02 sit in the tabular list?
Diseases of the circulatory system (I00-I99), in the block Ischemic heart diseases (I20-I25).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.