ICD-10 I31.1
Billable / Specific CCChronic constrictive pericarditis
About ICD-10-CM I31.1
ICD-10-CM code I31.1 represents Chronic constrictive pericarditis. This is a billable/specific code in the Circulatory System chapter (block I31). The 2026 edition of ICD-10-CM I31.1 became effective on October 1, 2025.
Coding Tips for I31.1
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
I31.1 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 I31.1. Per CMS ICD-10-CM Tabular 2026.
- Concretio cordis
- Pericardial calcification
Inpatient DRG Impact, CC
codes Chronic constrictive pericarditis. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for I31.1
Local Coverage Determinations (LCDs) from CMS MACs that list I31.1 as a covered diagnosis.
Showing top 10 of 299 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing I31.1.
1 Cigna
5 Medicare
1 Aetna
CPT Codes Commonly Billed with I31.1
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 83880 CMS LCD: Billing and Coding: B-type Natriuretic Peptide (BNP) Testing CMS LCD
Convert I31.1 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 |
|---|---|---|
| I31.1 | 4232 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To I31.1
Other codes in section I30-I5A (Other forms of heart disease).
ICD-10 I31.1, Billing FAQ
Is ICD-10 code I31.1 billable? +
Yes, I31.1 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 I31.1? +
ICD-10 I31.1 includes: Concretio cordis; Pericardial calcification.
Is I31.1 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 I31.1? +
Procedures frequently paired with I31.1 include: 83880.
What ICD-9 codes does I31.1 map to? +
Per CMS GEMs, I31.1 maps to ICD-9 codes: 4232. 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 May 31, 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