ICD-10 I01.1
Billable / Specific CCAcute rheumatic endocarditis
About ICD-10-CM I01.1
ICD-10-CM code I01.1 represents Acute rheumatic endocarditis. This is a billable/specific code in the Circulatory System chapter (block I01). The 2026 edition of ICD-10-CM I01.1 became effective on October 1, 2025.
Coding Tips for I01.1
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
I01.1 is designated CC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-CC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag CC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under I01.1. Per CMS ICD-10-CM Tabular 2026.
- Any condition in I00 with endocarditis or valvulitis
- Acute rheumatic valvulitis
Inpatient DRG Impact, CC
codes Acute rheumatic endocarditis. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for I01.1
Local Coverage Determinations (LCDs) from CMS MACs that list I01.1 as a covered diagnosis.
Showing top 10 of 317 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing I01.1.
2 Aetna
1 Cigna
5 Medicare
CPT Codes Commonly Billed with I01.1
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
Convert I01.1 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 |
|---|---|---|
| I01.1 | 3911 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To I01.1
Other codes in section I00-I02 (Acute rheumatic fever).
ICD-10 I01.1, Billing FAQ
Is ICD-10 code I01.1 billable? +
Yes, I01.1 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 I01.1? +
ICD-10 I01.1 includes: Any condition in I00 with endocarditis or valvulitis; Acute rheumatic valvulitis.
Is I01.1 a CC or MCC for inpatient DRG? +
Yes, this code is designated as CC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What CPT codes are commonly billed with I01.1? +
Procedures frequently paired with I01.1 include: C8925, C8927, C8926.
What ICD-9 codes does I01.1 map to? +
Per CMS GEMs, I01.1 maps to ICD-9 codes: 3911. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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