HCC 228: Acute Myocardial Infarction ICD-10-CM
CMS-HCC Category 228 (Acute Myocardial Infarction) is a payment HCC in the V28 Medicare Advantage risk adjustment model. For payment year 2026 it adds a risk adjustment factor between 0.252 and 0.517 to a beneficiary's RAF score depending on the payment segment (0.252 for a community, non-dual, aged enrollee). 18 ICD-10-CM diagnosis codes map to HCC 228. It sits at the top of its hierarchy: no other condition category supersedes it.
RAF Weight by Payment Segment 7 segments
| Payment Segment | Relative Factor |
|---|---|
| Community, non-dual, aged | 0.252 |
| Community, partial-benefit dual, aged | 0.324 |
| Community, full-benefit dual, aged | 0.493 |
| Community, non-dual, disabled | 0.254 |
| Community, partial-benefit dual, disabled | 0.407 |
| Community, full-benefit dual, disabled | 0.517 |
| Institutional | 0.310 |
A beneficiary is scored in exactly one segment, set by Medicaid (dual) status, aged or disabled entitlement, and residence. Factors are relative weights, not dollar amounts; new-enrollee segments score on demographics only. HCC 228 in turn supersedes HCC 229 (Unstable Angina and Other Acute Ischemic Heart Disease).
ICD-10-CM Codes That Map to HCC 228 18 codes
- I21.01 ST elevation (STEMI) myocardial infarction involving left main coronary artery from V24 HCC 86
- I21.02 ST elevation (STEMI) myocardial infarction involving left anterior descending coronary artery from V24 HCC 86
- I21.09 ST elevation (STEMI) myocardial infarction involving other coronary artery of anterior wall from V24 HCC 86
- I21.11 ST elevation (STEMI) myocardial infarction involving right coronary artery from V24 HCC 86
- I21.19 ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall from V24 HCC 86
- I21.21 ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery from V24 HCC 86
- I21.29 ST elevation (STEMI) myocardial infarction involving other sites from V24 HCC 86
- I21.3 ST elevation (STEMI) myocardial infarction of unspecified site from V24 HCC 86
- I21.4 Non-ST elevation (NSTEMI) myocardial infarction from V24 HCC 86
- I21.9 Acute myocardial infarction, unspecified from V24 HCC 86
- I21.A1 Myocardial infarction type 2 from V24 HCC 86
- I21.A9 Other myocardial infarction type from V24 HCC 86
- I21.B Myocardial infarction with coronary microvascular dysfunction from V24 HCC 86
- I22.0 Subsequent ST elevation (STEMI) myocardial infarction of anterior wall from V24 HCC 86
- I22.1 Subsequent ST elevation (STEMI) myocardial infarction of inferior wall from V24 HCC 86
- I22.2 Subsequent non-ST elevation (NSTEMI) myocardial infarction from V24 HCC 86
- I22.8 Subsequent ST elevation (STEMI) myocardial infarction of other sites from V24 HCC 86
- I22.9 Subsequent ST elevation (STEMI) myocardial infarction of unspecified site from V24 HCC 86
Every code above carries the full HCC 228 weight when documented and reported on a Medicare Advantage encounter. The code link opens its full page with the complete risk adjustment card.
Questions About HCC 228
What is HCC 228 in the CMS-HCC model?
HCC 228 is CMS-HCC Category 228 (Acute Myocardial Infarction) in the V28 risk adjustment model. It covers 18 ICD-10-CM diagnosis codes that raise a Medicare Advantage beneficiary's risk score when documented.
What is the RAF weight for HCC 228?
For payment year 2026, HCC 228 adds 0.252 to the RAF score of a community, non-dual, aged beneficiary (living at home, age 65 or over, not also enrolled in Medicaid). The published weights range from 0.252 to 0.517 across the seven payment segments shown above.
Related References
Source: Centers for Medicare & Medicaid Services, Payment Year 2026 risk adjustment mapping and model software releases (CMS-HCC V28), applied to the FY 2026 ICD-10-CM code set. ICD List is not affiliated with CMS.
