ICD-10-CM 2027
ICD-10 code for pericarditis
From the official ICD-10-CM alphabetic index entry “Pericarditis (with decompensation) (with effusion)”. Page updated September 29, 2026.
About coding pericarditis
The ICD-10-CM code for pericarditis is I31.9 (Disease of pericardium, unspecified). The official index lists 45 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on I31.9.
Within I31, choose I31.9 (Disease of pericardium, unspecified) only when documentation doesn't support a more specific option: chronic adhesive pericarditis (I31.0), chronic constrictive pericarditis (I31.1), hemopericardium, not elsewhere classified (I31.2), pericardial effusion (noninflammatory) (I31.3), cardiac tamponade (I31.4) and other specified diseases of pericardium (I31.8).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 314 (Other Circulatory System Diagnoses with MCC, relative weight 2.0873), DRG 315 (Other Circulatory System Diagnoses with CC, relative weight 0.9508) and DRG 316 (Other Circulatory System Diagnoses without CC/MCC, relative weight 0.6677), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific pericarditis codes (official index)
- with rheumatic fever (conditions in I00)
- active
- inactive or quiescent I09.2 — Chronic rheumatic pericarditis
- acute (hemorrhagic) (nonrheumatic) (Sicca) I30.9 — Acute pericarditis, unspecified
- with chorea (acute) (rheumatic) (Sydenham's) I02.0 — Rheumatic chorea with heart involvement
- benign I30.8 — Other forms of acute pericarditis
- nonspecific I30.0 — Acute nonspecific idiopathic pericarditis
- rheumatic I01.0 — Acute rheumatic pericarditis
- with chorea (acute) (Sydenham's) I02.0 — Rheumatic chorea with heart involvement
- adhesive or adherent (chronic) (external) (internal) I31.0 — Chronic adhesive pericarditis
- acute
- rheumatic I09.2 — Chronic rheumatic pericarditis
- bacterial (acute) (subacute) (with serous or seropurulent effusion) I30.1 — Infective pericarditis
- calcareous I31.1 — Chronic constrictive pericarditis
- cholesterol (chronic) I31.8 — Other specified diseases of pericardium
- acute I30.9 — Acute pericarditis, unspecified
- chronic (nonrheumatic) I31.9 — Disease of pericardium, unspecified
- rheumatic I09.2 — Chronic rheumatic pericarditis
- constrictive (chronic) I31.1 — Chronic constrictive pericarditis
- coxsackie B33.23 — Viral pericarditis
- fibrinocaseous (tuberculous) A18.84 — Tuberculosis of heart
- fibrinopurulent I30.1 — Infective pericarditis
- fibrinous I30.8 — Other forms of acute pericarditis
- fibrous I31.0 — Chronic adhesive pericarditis
- gonococcal A54.83 — Gonococcal heart infection
- idiopathic I30.0 — Acute nonspecific idiopathic pericarditis
- in systemic lupus erythematosus M32.12 — Pericarditis in systemic lupus erythematosus
- infective I30.1 — Infective pericarditis
- meningococcal A39.53 — Meningococcal pericarditis
- neoplastic (chronic) I31.8 — Other specified diseases of pericardium
- acute I30.9 — Acute pericarditis, unspecified
- obliterans, obliterating I31.0 — Chronic adhesive pericarditis
- plastic I31.0 — Chronic adhesive pericarditis
- pneumococcal I30.1 — Infective pericarditis
- postinfarction I24.1 — Dressler's syndrome
- purulent I30.1 — Infective pericarditis
- rheumatic (active) (acute) (with effusion) (with pneumonia) I01.0 — Acute rheumatic pericarditis
- with chorea (acute) (rheumatic) (Sydenham's) I02.0 — Rheumatic chorea with heart involvement
- chronic or inactive (with chorea) I09.2 — Chronic rheumatic pericarditis
- rheumatoid
- septic I30.1 — Infective pericarditis
- serofibrinous I30.8 — Other forms of acute pericarditis
- staphylococcal I30.1 — Infective pericarditis
- streptococcal I30.1 — Infective pericarditis
- suppurative I30.1 — Infective pericarditis
- syphilitic A52.06 — Other syphilitic heart involvement
- tuberculous A18.84 — Tuberculosis of heart
- uremic N18.9 — Chronic kidney disease, unspecified
- viral I30.1 — Infective pericarditis
Common questions about pericarditis ICD-10 codes
What is the ICD-10 code for pericarditis?
- I31.9 — Disease of pericardium, unspecified. More specific codes apply when the documentation supports them: I09.2, I30.9, I02.0, I30.8 and others below.
What is the ICD-10 code for acute pericarditis?
- I30.9 — Acute pericarditis, unspecified.
What is the ICD-10 code for adhesive or adherent pericarditis?
- I31.0 — Chronic adhesive pericarditis.
What is the ICD-10 code for bacterial pericarditis?
- I30.1 — Infective pericarditis.
What is the ICD-10 code for calcareous pericarditis?
- I31.1 — Chronic constrictive pericarditis.
What is the ICD-10 code for cholesterol pericarditis?
- I31.8 — Other specified diseases of pericardium.
What is the ICD-10 code for chronic pericarditis?
- I31.9 — Disease of pericardium, unspecified.
Is I31.9 billable?
- Yes. I31.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I31.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I31.9 as a principal diagnosis.
Is I31.9 a CC or MCC?
- I31.9 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.