I50.9
BillableHeart failure, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is I50.9 an HCC code?
Yes. I50.9 maps to Heart Failure, Specified under the CMS-HCC V28 risk adjustment model (and Congestive Heart Failure under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for I50.9
For I50.9 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed I50.9 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
I50.9 is the ICD-10-CM diagnosis code for heart failure, unspecified. Heart failure without a specified type or cause. This is used when the heart is unable to pump blood effectively but the specific classification (systolic, diastolic, or combined) is not documented. I50.9 sits in the ICD-10-CM chapter for diseases of the circulatory system (i00-i99), within the section covering other forms of heart disease (i30-i5a).
Under the CMS-HCC V28 risk adjustment model, I50.9 maps to Heart Failure, Specified (HCC 226) with a community, non-dual, aged base RAF weight of 0.000. Under the older CMS-HCC V24 model, I50.9 maps to Congestive Heart Failure (HCC 85) with a community, non-dual, aged base RAF weight of 0.368. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Query the provider for more specific heart failure type (systolic, diastolic, or combined) to assign a more specific code. Because I50.9 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for I50.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Query the provider for more specific heart failure type (systolic, diastolic, or combined) to assign a more specific code
- •Verify if acute or chronic heart failure is documented, as this affects code selection
Clinical Significance
Heart failure, unspecified, is the least specific heart failure code and should be used only as a last resort when documentation provides no detail about the type, acuity, or affected ventricle. While it still maps to an HCC in V24, it represents a missed opportunity for more accurate risk stratification and clinical documentation.
Documentation Requirements
- ✓Provider must document heart failure as an active diagnosis
- ✓This code should only be used when documentation does not specify systolic, diastolic, combined, right-sided, or end stage heart failure
- ✓Query the provider for additional specificity before defaulting to this code
- ✓Current medications suggesting heart failure management
- ✓Signs and symptoms of heart failure present during the encounter
- ✓Consider requesting echocardiogram results to determine ejection fraction and type
Excludes 2 — Not included here, may code separately
- fluid overload unrelated to congestive heart failure (E87.70)
Commonly Confused Codes
- •I50.1 — Left ventricular failure, unspecified: slightly more specific, identifying left ventricle
- •I50.20 — Unspecified systolic heart failure: use when systolic dysfunction is documented
- •I50.30 — Unspecified diastolic heart failure: use when diastolic dysfunction is documented
- •I50.810 — Right heart failure, unspecified: use when right heart failure is specified
- •I50.89 — Other heart failure: use for heart failure types not classified elsewhere