2027 ICD-10-CM Diagnosis Code I39Endocarditis and heart valve disorders in diseases classified elsewhere
ICD-10-CM Codes›I00–I99›I30-I5A›I39
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
I39 is a billable ICD-10-CM diagnosis code for endocarditis and heart valve disorders in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 306 through 307, 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 8 closely related codes. The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Endocarditis and endocardial disease.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for I39.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abnormality of atrioventricular valve leaflet in atrioventricular septal defect
- Abnormality of common atrioventricular valve chordae tendinae
- Abnormality of common atrioventricular valve in atrioventricular septal defect
- Abnormality of common atrioventricular valve papillary muscle
- Abnormality of left atrioventricular valve chordae tendinae
- Abnormality of left atrioventricular valve in double inlet ventricle
- Abnormality of right atrioventricular valve chordae tendinae
- Abnormality of right atrioventricular valve in double inlet ventricle
- Abnormality of truncal valve cusp
- Accessory tissue on common atrioventricular valve leaflet
- Accessory tissue on left atrioventricular valve leaflet
- Accessory tissue on right atrioventricular valve leaflet
- African histoplasmosis
- Arcade abnormality of common atrioventricular valve chordae
- Arcade abnormality of left atrioventricular valve chordae
- Common atrioventricular valve chordae too long
- Common atrioventricular valve leaflet abnormality
- Common atrioventricular valve limited to one ventricle
- Common atrioventricular valve stenosis
- Congenital abnormality of left atrioventricular valve papillary muscle
- Congenital abnormality of right atrioventricular valve papillary muscle
- Deficiency of truncal valve cusp
- Double orifice of left atrioventricular valve
- Double orifice of right atrioventricular valve
- Dysplasia of common atrioventricular valve
- Endocarditis associated with another disorder
- Fenestration of atrioventricular valve leaflet in atrioventricular septal defect
- Fenestration of truncal valve cusp
- Histoplasma capsulatum with endocarditis
- Histoplasma duboisii with endocarditis
- Hypoplasia of common atrioventricular valve
- Hypoplastic common atrioventricular valve papillary muscle
- Left atrioventricular valve chordae to outlet septum
- Left atrioventricular valve chordae too long
- Left atrioventricular valve chordae too short
- Left atrioventricular valve dysplasia
- Left atrioventricular valve hypoplasia
- Left atrioventricular valve leaflet abnormality
- Left atrioventricular valve leaflet dysplasia
- Left atrioventricular valve prolapse
- Left atrioventricular valve stenosis
- Mycotic endocarditis
- Quadricuspid truncal valve
- Regurgitation of common atrioventricular valve
- Right atrioventricular valve chordae to outlet septum
- Right atrioventricular valve dysplasia
- Right atrioventricular valve hypoplasia
- Right atrioventricular valve leaflet abnormality
- Right atrioventricular valve stenosis
- Straddling left atrioventricular valve
- Straddling right atrioventricular valve
- Tricuspid truncal valve
- Triple orifice of left ventricular component of common atrioventricular valve
- Truncal valve prolapse
- Truncal valve regurgitation
- Truncal valve stenosis
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to I39: its own notes plus those printed at Chapter 9. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- transient cerebral ischemic attacks and related syndromes (G45.-)
Code First
The underlying condition named in the note is sequenced before this code.
- underlying disease, such as:
- Q fever (A78)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name I39, its category, or a range that includes it.
Use Additional Code 1
These codes say to use an additional code from the note, and I39 is one of the codes named.
- B39 Histoplasmosisendocarditis (I39)
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Endocarditis
Endocarditis is sometimes called infective endocarditis. It's a rare but life-threatening inflammation of the lining inside your heart's chambers and valves (the endocardium).
The full article covers:
- What is endocarditis?
- What causes endocarditis?
- Who is more likely to develop endocarditis?
- What are the symptoms of endocarditis?
- What other problems can endocarditis cause?
- How is endocarditis diagnosed?
- What are the treatments for endocarditis?
- Can endocarditis be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert I39 to ICD-9-CMHistory
Code HistoryHistory
Questions About I39Overview
Is I39 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report endocarditis and heart valve disorders in diseases classified elsewhere on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does I39 group to?
On inpatient claims, endocarditis and heart valve disorders in diseases classified elsewhere maps to MS-DRG 306, 793, 791, 307, with relative weights from 0.9146 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.
Is I39 a CC or MCC?
CMS lists I39 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 8 closely related codes in its exclusion list.
Can I39 be a principal diagnosis?
No. This is a manifestation code: endocarditis and heart valve disorders in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
Can I39 be reported with B37.6?
Not as a rule. The Excludes1 note on I39 lists "candidiasis (B37.6)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
