ICD-10 I20.9
Billable / Specific HCC v28: 88Angina pectoris, unspecified
About ICD-10-CM I20.9
ICD-10-CM code I20.9 represents Angina pectoris, unspecified. This is a billable/specific code in the Circulatory System chapter (block I20). The 2026 edition of ICD-10-CM I20.9 became effective on October 1, 2025.
Coding Tips for I20.9
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
I20.9 is a CMS-HCC v28 risk-adjustment code (category 88). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under I20.9. Per CMS ICD-10-CM Tabular 2026.
- Angina NOS
- Anginal syndrome
- Cardiac angina
- Ischemic chest pain
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Medicare LCD Coverage for I20.9
Local Coverage Determinations (LCDs) from CMS MACs that list I20.9 as a covered diagnosis.
Showing top 10 of 479 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing I20.9.
2 Aetna
3 Cigna
5 Medicare
CPT Codes Commonly Billed with I20.9
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 93015 Stress test — chest pain, palpitations, syncope, known CAD Cardiovascular Disease
- 93458 Left heart catheterization — CAD, ACS, chest pain Cardiovascular Disease
- 93015 Stress test cardiovascular — chest pain, CAD, angina, tachycardia, dyspnea, HTN, diabetes, syncope, cardiac screening Cardiology
- 93350 Stress echo — known/suspected CAD, chest pain, angina, abnormal EKG, cardiomyopathy, HF, dyspnea Cardiology
- 92979 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
- C9607 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
- C9600 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
- 92937 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
- 92920 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
- C9608 CMS LCD: Billing and Coding: Percutaneous Coronary Interventions CMS LCD
Convert I20.9 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| I20.9 | 4139 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To I20.9
Other codes in section I20-I25 (Ischemic heart diseases).
ICD-10 I20.9, Billing FAQ
Is ICD-10 code I20.9 billable? +
Yes, I20.9 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to I20.9? +
ICD-10 I20.9 includes: Angina NOS; Anginal syndrome; Cardiac angina, and 1 more clinical synonyms.
Does I20.9 affect Medicare Advantage HCC risk adjustment? +
Yes. I20.9 maps to CMS-HCC v28 category 88. Capture this diagnosis annually for accurate Medicare Advantage risk score.
What CPT codes are commonly billed with I20.9? +
Procedures frequently paired with I20.9 include: 93015, 93458, 93015, 93350, 92979.
What ICD-9 codes does I20.9 map to? +
Per CMS GEMs, I20.9 maps to ICD-9 codes: 4139. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 17, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team