I51.8
Non-billableOther ill-defined heart diseases
Other ill-defined heart diseases
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •systemic connective tissue disordersM30-M36
- •transient cerebral ischemic attacks and related syndromesG45
Child Codes (2)
Related Codes(8)
I51.0Cardiac septal defect, acquired
I51.1Rupture of chordae tendineae, not elsewhere classified
I51.2Rupture of papillary muscle, not elsewhere classified
I51.3Intracardiac thrombosis, not elsewhere classified
I51.4Myocarditis, unspecified
I51.5Myocardial degeneration
I51.7Cardiomegaly
I51.9Heart disease, unspecified
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(1)
Frequently Asked Questions
What is the ICD-10 code for other ill-defined heart diseases?
The ICD-10-CM code for other ill-defined heart diseases is I51.8. The full clinical description is "Other ill-defined heart diseases". I51.8 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code I51.8 mean?
ICD-10-CM code I51.8 represents “Other ill-defined heart diseases”. It is classified under Chapter 9: Diseases of the Circulatory System and is a non-billable header code. Use a more specific child code for billing purposes.
Is I51.8 a billable code?
No, I51.8 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 2 child codes under I51.8.
What chapter is I51.8 in?
I51.8 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
What codes cannot be used with I51.8?
I51.8 has Excludes1 notes indicating codes that cannot be used together with it, including: any condition in I51.4-I51.9 due to hypertension (I11.-); any condition in I51.4-I51.9 due to hypertension and chronic kidney disease (I13.-); heart disease specified as rheumatic (I00-I09).
What are the subcategories under I51.8?
I51.8 has 2 child codes, including: I51.81 (Takotsubo syndrome), I51.89 (Other ill-defined heart diseases).
What are the UMLS CUIs for I51.8?
I51.8 is linked to 1 UMLS Concept Unique Identifier: C0155717. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I51.8 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like other ill-defined heart diseases affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of I51.8?
I51.8 maps to the ICD-11 code: BC4Z (Diseases of the myocardium or cardiac chambers, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.