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I22.8

I22.8Subsequent ST elevation (STEMI) myocardial infarction of other sites

Billable / specific codeICD-10-CM

I22.8 is a billable, specific ICD-10-CM code for subsequent st elevation (stemi) myocardial infarction of other sites. It is valid for submission on a claim.

Inclusion terms

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

  • Subsequent acute transmural myocardial infarction of other sites
  • Subsequent apical-lateral transmural (Q wave) myocardial infarction (acute)
  • Subsequent basal-lateral transmural (Q wave) myocardial infarction (acute)
  • Subsequent high lateral transmural (Q wave) myocardial infarction (acute)
  • Subsequent transmural (Q wave) myocardial infarction (acute)(of) lateral (wall) NOS
  • Subsequent posterior (true) transmural (Q wave) myocardial infarction (acute)
  • Subsequent posterobasal transmural (Q wave) myocardial infarction (acute)
  • Subsequent posterolateral transmural (Q wave) myocardial infarction (acute)
  • Subsequent posteroseptal transmural (Q wave) myocardial infarction (acute)
  • Subsequent septal NOS transmural (Q wave) myocardial infarction (acute)

Excludes1 inherited from the categories above I22.8

These are not written on I22.8, but they bind it: a note on a category applies to every code beneath it. Billing I22.8 with anything listed here is a denial.

Written on I22 Subsequent ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction

  • subsequent myocardial infarction, type 2 (I21.A1)
  • subsequent myocardial infarction of other type (type 3) (type 4) (type 5) (I21.A9)

Other codes that can never be billed with I22.8

These codes carry an Excludes1 note pointing at I22.8. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading I22.8 alone.

  • I25.82Chronic total occlusion of coronary artery

Risk adjustment

I22.8 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

I22.8 is named in 62 Medicare coverage policies 62 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 I22.8 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 I22.8.

  • Infarct, infarctionmyocardium, myocardialsubsequentlateral(apical-lateral) (basal-lateral) (high)
  • Infarct, infarctionmyocardium, myocardialsubsequentposterior(posterobasal) (posterolateral) (posteroseptal) (true)
  • Infarct, infarctionmyocardium, myocardialsubsequentseptal
  • Infarct, infarctionmyocardium, myocardialsubsequentspecified NEC
  • Infarct, infarctionmyocardium, myocardialST elevationlateralsubsequent
  • Infarct, infarctionmyocardium, myocardialST elevationposteriorsubsequent
  • Infarct, infarctionmyocardium, myocardialST elevationseptalsubsequent
  • Infarct, infarctionmyocardium, myocardialST elevationspecified NECsubsequent
  • Infarct, infarctionmyocardium, myocardialsubsequentST elevationspecified NEC
  • Infarct, infarctionmyocardium, myocardialsubsequenttransmurallateral(apical-lateral) (basal-lateral) (high)
  • Infarct, infarctionmyocardium, myocardialsubsequenttransmuralposterior(posterobasal) (posterolateral) (posteroseptal) (true)
  • Infarct, infarctionmyocardium, myocardialsubsequenttransmuralspecified NEC

Code history

I22.8 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share I22. If I22.8 is not quite right, the correct code is usually one of these.

Questions about I22.8

Is I22.8 a billable ICD-10-CM code?
Yes. I22.8 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does I22.8 sit in the tabular list?
Diseases of the circulatory system (I00-I99), in the block Ischemic heart diseases (I20-I25).
What cannot be coded together with I22.8?
I22.8 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above I22.8 (I22) and apply to it just the same.
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.