I33 ICD-10-CM Code: Acute and subacute endocarditis
A clear reference for the official code description, hierarchy, and related coding information from the FY 2027 U.S. release.
Official description
I33Acute and subacute endocarditis
ICD-10-CM diagnosis code · United States clinical modification
Where I33 sits
- 1
Chapter 9
Diseases of the circulatory system (I00-I99)
- 2
Section
Other forms of heart disease (I30-I5A)
- 3
Category I33
Acute and subacute endocarditis
- 4
Code I33
Acute and subacute endocarditis
Codes under I33
I33 is a non-billable category. Choose the child code that best matches the documented diagnosis.
Notes for this code
Inclusion terms
No inclusion terms are listed for I33.
Code first
No “code first” instruction is listed for I33.
Use additional code
No “use additional code” instruction is listed for I33.
Excludes1
Conditions that should not be reported together with this code.
- acute rheumatic endocarditis (I01.1)
- endocarditis NOS (I38)
Excludes2
Conditions not included here that may be reported separately when present.
No Excludes2 note is listed for I33.
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code I33 mean?
I33 is the FY 2027 U.S. ICD-10-CM code for “Acute and subacute endocarditis.”
Is I33 a billable or specific ICD-10-CM code?
No. I33 has more specific child codes in the FY 2027 reference data. Select the code that matches the documentation and confirm the active code set and payer requirements.
Where is I33 located in ICD-10-CM?
I33 is listed in Chapter 9, Diseases of the circulatory system (I00-I99), within Other forms of heart disease (I30-I5A) (I30–I5A), under category I33, Acute and subacute endocarditis.
What coding notes are listed for I33?
No inclusion terms are listed for I33 in this reference record. No code-first instruction is listed. Excludes1 notes: acute rheumatic endocarditis (I01.1); endocarditis NOS (I38). No Excludes2 note is listed.