Q87.418
BillableMarfan syndrome with other cardiovascular manifestations
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Q87.418 an HCC code?
No. Q87.418 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
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 Q87.418
For Q87.418to 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 Q87.418 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
Q87.418 is the ICD-10-CM diagnosis code for marfan syndrome with other cardiovascular manifestations. Marfan syndrome with heart and blood vessel problems other than aortic dilation, such as mitral valve prolapse or other cardiac structural abnormalities. Q87.418 sits in the ICD-10-CM chapter for congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (q00-qa0), within the section covering other congenital malformations (q80-q89).
Q87.418 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
Maps to RxHCC 84 (Muscular Dystrophy) with RAF weight 0.0 in the RxHCC model only. The condition does not impact CMS-HCC risk scores despite requiring intensive cardiovascular monitoring and specialized care coordination. Coders reviewing Q87.418 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC — capturing the correct specificity is the highest-leverage RAF improvement available within accurate coding.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q87.418 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Specify the exact cardiovascular manifestation in documentation for clarity and appropriate management
- •Ensure echocardiography findings are documented to support the cardiovascular diagnosis
Clinical Significance
Marfan syndrome with cardiovascular manifestations beyond aortic dilation indicates complex cardiac involvement requiring specialized care. These manifestations may include mitral valve prolapse, arrhythmias, or other structural heart defects that significantly impact patient outcomes and care requirements.
Documentation Requirements
- ✓Confirmed diagnosis of Marfan syndrome
- ✓Specific cardiovascular manifestations identified
- ✓Echocardiogram findings detailing cardiac abnormalities
- ✓EKG results if arrhythmias are present
- ✓Cardiology evaluation and recommendations
- ✓Documentation excluding aortic dilation as primary manifestation
- ✓Assessment of functional cardiac status
- ✓Treatment plan for cardiovascular complications