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I22.2 ICD-10-CM Code: Subsequent non-ST elevation (NSTEMI) myocardial infarction

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 280 — ACUTE MYOCARDIAL INFARCTION, DISCHARGED ALIVE WITH MCC (MDC 05)
  • MS-DRG 281 — ACUTE MYOCARDIAL INFARCTION, DISCHARGED ALIVE WITH CC (MDC 05)
  • MS-DRG 282 — ACUTE MYOCARDIAL INFARCTION, DISCHARGED ALIVE WITHOUT CC/MCC (MDC 05)
  • MS-DRG 283 — ACUTE MYOCARDIAL INFARCTION, EXPIRED WITH MCC (MDC 05)
  • MS-DRG 284 — ACUTE MYOCARDIAL INFARCTION, EXPIRED WITH CC (MDC 05)
  • MS-DRG 285 — ACUTE MYOCARDIAL INFARCTION, EXPIRED WITHOUT CC/MCC (MDC 05)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 228 — Acute Myocardial Infarction (supersedes HCC 229)

Other models: CMS-HCC V22 HCC 86 · RxHCC V08 HCC 188

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for I22.2 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on I22.2 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • acute myocardial infarction occurring within four weeks (28 days) of a previous acute myocardial infarction, regardless of site
  • cardiac infarction
  • coronary (artery) embolism
  • coronary (artery) occlusion
  • coronary (artery) rupture
  • coronary (artery) thrombosis
  • infarction of heart, myocardium, or ventricle
  • recurrent myocardial infarction
  • reinfarction of myocardium
  • rupture of heart, myocardium, or ventricle
  • subsequent type 1 myocardial infarction

Source: inherited from I22

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Subsequent acute subendocardial myocardial infarction
  • Subsequent non-Q wave myocardial infarction NOS
  • Subsequent nontransmural myocardial infarction NOS

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from I22

Code Also

Additional codes that may be required to fully describe the encounter.

  • the presence of hypertension (I10-I1A)

Source: inherited from I20-I25

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code, if applicable, to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Source: inherited from I22

Coder workflow for I22.2

MedCoder structured workflow — derived from this code’s own official record

Before you code I22.2

  1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with I22.2. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in I22.2’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewI21.A1, I21.A9

Consider I22.2. Then work the Use Additional Code note and review the Code Also note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
The conditions the Use Additional Code note names
Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.

Official instructions as workflow

  • Excludes1 — check before selecting I22.2(2 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with I22.2: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareI21.A1, I21.A9

    See the official tabular notes · Guidelines I.A.12.a

  • Use Additional Code — after identifying I22.2(7 notes)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with I22.2 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    ReviewZ77.22, Z87.891, Z57.31, Z92.82, F17, Z72.0

    See the official tabular notes · Guidelines I.A.13

  • Code Also — related condition(1 note)

    Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

    See the official tabular notes · Guidelines I.A.17

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition I22.2 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewI21.A1, I21.A9

Documentation: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with I22.2?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

ReviewZ77.22, Z87.891, Z57.31, Z92.82, F17, Z72.0

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Subsequent non-ST elevation (NSTEMI) myocardial infarction is a billable ICD-10-CM diagnosis code (I22.2).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (3)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Official Coding Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Verbatim excerpts from the ICD-10-CM Official Guidelines for Coding and Reporting (CMS/NCHS) that govern this code.

Chapter 9: Diseases of the Circulatory System (I00 -I99)

4) Subsequent acute myocardial infarction A code from category I22, Subsequent ST elevation (STEMI) and non- ST elevation (NSTEMI) myocardial infarction, is to be used when a patient who has suffered a type 1 or unspecified AMI has a new AMI within the 4 week time frame of the initial AMI. A code from category I22 must be used in conjunction with a code from category I21. The sequencing of the I22 and I21 codes depends on the circumstances of the encounter.

Chapter 9: Diseases of the Circulatory System (I00 -I99)

Do not assign code I22 for subsequent myocardial infarctions other than type 1 or unspecified. For subsequent type 2 AMI assign only code I21.A1. For subsequent type 4 or type 5 AMI, assign only code I21.A9.

Chapter 9: Diseases of the Circulatory System (I00 -I99)

If a subsequent myocardial infarction of one type occurs within 4 weeks of a myocardial infarction of a different type, assign the appropriate codes from category I21 to identify each type. Do not assign a code from I22. Codes from category I22 should only be assigned if both the initial and subsequent myocardial infarctions are type 1 or unspecified.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

  1. 7 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
  2. 1 Code Also note — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
  3. 2 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

  • MCC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name I22.2 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: I25.82 — Chronic total occlusion of coronary artery (via I22.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 3 Excludes2 notes: I21 — Acute myocardial infarction (via I22.-), I74 — Arterial embolism and thrombosis (via I22.-), I82 — Other venous embolism and thrombosis (via I22.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code First instruction: Z92.82 — Status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (via I22.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: MCC — Major Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 25 clinically related codes on its CMS exclusion list. Does not count toward severity when the stay groups to DRGs 280-282 (Acute Myocardial Infarction, Discharged Alive); DRGs 283-285 (Acute Myocardial Infarction, Expired).

Named in the grouper logic of 6 MS-DRGs: DRG 280 (MDC 05), DRG 281 (MDC 05), DRG 282 (MDC 05), DRG 283 (MDC 05), DRG 284 (MDC 05), DRG 285 (MDC 05).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):CIR009 — Acute myocardial infarction (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as MCC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

I21.19 — ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall, I21.21 — ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery, I21.29 — ST elevation (STEMI) myocardial infarction involving other sites, I21.3 — ST elevation (STEMI) myocardial infarction of unspecified site, I21.4 — Non-ST elevation (NSTEMI) myocardial infarction, I21.9 — Acute myocardial infarction, unspecified, I21.A1 — Myocardial infarction type 2, I21.A9 — Other myocardial infarction type, I21.B — Myocardial infarction with coronary microvascular dysfunction, I22.0 — Subsequent ST elevation (STEMI) myocardial infarction of anterior wall, I22.1 — Subsequent ST elevation (STEMI) myocardial infarction of inferior wall, I22.8 — Subsequent ST elevation (STEMI) myocardial infarction of other sites, I22.9 — Subsequent ST elevation (STEMI) myocardial infarction of unspecified site, I27.841 — Fontan-associated lymphatic dysfunction, I27.848 — Other Fontan-associated condition, I27.849 — Fontan related circulation, unspecified, I87.8 — Other specified disorders of veins, I87.9 — Disorder of vein, unspecified, I99.8 — Other disorder of circulatory system, I99.9 — Unspecified disorder of circulatory system, +4 more

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Acute Myocardial Infarction) for risk-adjusted payment.

I21.01 — ST elevation (STEMI) myocardial infarction involving left main coronary artery, I21.02 — ST elevation (STEMI) myocardial infarction involving left anterior descending coronary artery, I21.09 — ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wall, I21.11 — ST elevation (STEMI) myocardial infarction involving right coronary artery, I21.19 — ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall, I21.21 — ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery, I21.29 — ST elevation (STEMI) myocardial infarction involving other sites, I21.3 — ST elevation (STEMI) myocardial infarction of unspecified site, I21.4 — Non-ST elevation (NSTEMI) myocardial infarction, I21.9 — Acute myocardial infarction, unspecified, I21.A1 — Myocardial infarction type 2, I21.A9 — Other myocardial infarction type, I21.B — Myocardial infarction with coronary microvascular dysfunction, I22.0 — Subsequent ST elevation (STEMI) myocardial infarction of anterior wall, I22.1 — Subsequent ST elevation (STEMI) myocardial infarction of inferior wall, I22.8 — Subsequent ST elevation (STEMI) myocardial infarction of other sites, I22.9 — Subsequent ST elevation (STEMI) myocardial infarction of unspecified site

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Unstable Angina and Other Acute Ischemic Heart Disease

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Acute myocardial infarction).

I21.01 — ST elevation (STEMI) myocardial infarction involving left main coronary artery, I21.02 — ST elevation (STEMI) myocardial infarction involving left anterior descending coronary artery, I21.09 — ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wall, I21.11 — ST elevation (STEMI) myocardial infarction involving right coronary artery, I21.19 — ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall, I21.21 — ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery, I21.29 — ST elevation (STEMI) myocardial infarction involving other sites, I21.3 — ST elevation (STEMI) myocardial infarction of unspecified site, I21.4 — Non-ST elevation (NSTEMI) myocardial infarction, I21.9 — Acute myocardial infarction, unspecified, I21.A1 — Myocardial infarction type 2, I21.A9 — Other myocardial infarction type, I21.B — Myocardial infarction with coronary microvascular dysfunction, I22.0 — Subsequent ST elevation (STEMI) myocardial infarction of anterior wall, I22.1 — Subsequent ST elevation (STEMI) myocardial infarction of inferior wall, I22.8 — Subsequent ST elevation (STEMI) myocardial infarction of other sites, I22.9 — Subsequent ST elevation (STEMI) myocardial infarction of unspecified site

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Infarct, infarction”; these codes share that main term but sit in a different category of the Tabular List.

I21.11 — ST elevation (STEMI) myocardial infarction involving right coronary artery (myocardium, myocardial, transmural, inferoposterior), I21.19 — ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall (myocardium, myocardial, transmural, inferior NEC), I21.21 — ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery (myocardium, myocardial, ST elevation, involving, left circumflex coronary artery), I21.29 — ST elevation (STEMI) myocardial infarction involving other sites (myocardium, myocardial, ST elevation, septal), I21.3 — ST elevation (STEMI) myocardial infarction of unspecified site (myocardium, myocardial, Q wave), I21.4 — Non-ST elevation (NSTEMI) myocardial infarction (nontransmural), I21.9 — Acute myocardial infarction, unspecified (myocardium, myocardial), I21.A1 — Myocardial infarction type 2 (myocardium, myocardial, type 2), I21.A9 — Other myocardial infarction type (myocardium, myocardial, type 3), I21.B — Myocardial infarction with coronary microvascular dysfunction (myocardium, myocardial, with, coronary microvascular disease), I25.2 — Old myocardial infarction (myocardium, myocardial, past), I63.0 — Cerebral infarction due to thrombosis of precerebral arteries (cerebral, due to, thrombosis, precerebral artery), I63.1 — Cerebral infarction due to embolism of precerebral arteries (cerebral, due to, embolism, precerebral arteries), I63.2 — Cerebral infarction due to unspecified occlusion or stenosis of precerebral arteries (cerebral, due to, stenosis NEC, precerebral arteries), I63.3 — Cerebral infarction due to thrombosis of cerebral arteries (cerebral, due to, thrombosis, cerebral artery), I63.4 — Cerebral infarction due to embolism of cerebral arteries (cerebral, due to, embolism, cerebral arteries), I63.5 — Cerebral infarction due to unspecified occlusion or stenosis of cerebral arteries (cerebral, due to, stenosis NEC, cerebral arteries), I63.6 — Cerebral infarction due to cerebral venous thrombosis, nonpyogenic (cerebral, due to, cerebral venous thrombosis, nonpyogenic), I63.81 — Other cerebral infarction due to occlusion or stenosis of small artery (lacunar), I63.89 — Other cerebral infarction (cerebral, specified NEC), +51 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Blood Glucose Test, Lipid Panel, Partial Thromboplastin Time (PTT) Test, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of I22.2 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run I22.2 with these 5 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Excludes2 notes

Referenced by Code First instructions

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 228 — Acute Myocardial Infarction [CMS-HCC]: “Acute Myocardial Infarction — supersedes HCC 229 (Unstable Angina and Other Acute Ischemic Heart Disease)”— CMS-HCC V28 · 2026

MS-DRG Grouper

MDC crossing

  • MDC 05 — Diseases and Disorders of the Circulatory System[MDC crossing]: “Diseases and Disorders of the Circulatory System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 15,708 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries

  • Infarct, infarction, myocardium, myocardial (acute) (with stated duration of 4 weeks or less), non-ST elevation (NSTEMI), subsequent[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Infarct, infarction, myocardium, myocardial (acute) (with stated duration of 4 weeks or less), subsequent (recurrent) (reinfarction), non-ST elevation (NSTEMI)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Infarct, infarction, myocardium, myocardial (acute) (with stated duration of 4 weeks or less), subsequent (recurrent) (reinfarction), subendocardial[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Coding guidelines Official source data
ICD-10-CM Official Guidelines for Coding and Reporting (FY2027), quoted by section Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "I22.2 — Subsequent non-ST elevation (NSTEMI) myocardial infarction." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/i22.2-subsequent-non-st-elevation-nstemi-myocardial-infarction

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Subsequent non-ST elevation (NSTEMI) myocardial infarction

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to I22.2 in its code family, with their registry titles.

View all codes in the I22 family