I51 Complications and ill-defined descriptions of heart disease
The ICD-10-CM code for Complications and ill-defined descriptions of heart disease is I51 (FY2026). It is a non-billable category code — select a more specific code below for claims.
Classification
- Section
- I30-I5A: Other forms of heart disease (I30-I5A)
- Category I51
- 12 codes (10 billable)
- FY2026 Status
- Stable since FY2024
Official Coding Guidelines
I11 + addl code for I50/I51 heart conditions (incl I50.-, I51.4, I51.89, I51.9)1) Hypertension with Heart Disease Hypertension with heart conditions classified to I50.-, Heart failure, I51.4, Myocarditis, unspecified, I51.89, Other ill-defined heart diseases, and I51.9, Heart disease, unspecified, is assigned to a code from category I11, Hypertensive heart disease. Use additional code(s) from category I50, Heart failure, or I51, Complications and ill-defined descriptions of heart disease, to identify the heart condition.
Presumed relationship due to Index term “with”The classification presumes a causal relationship between hypertension and heart involvement and between hypertension and kidney involvement, as the two conditions are linked by the term “with” in the Alphabetic Index. These conditions should be coded as related even in the absence of provider documentation explicitly linking them, unless the documentation clearly states the conditions are unrelated.
Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026