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. 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.
