I51: Complications and ill-defined descriptions of heart disease
Codes under I51 (Complications and ill-defined descriptions of heart disease). A ✓ marks a billable (fully specified) code; category codes without a ✓ are not billable on their own.
| Code | Description | Billable |
|---|---|---|
| I51.0 | Cardiac septal defect, acquired | ✓ |
| I51.0 | Cardiac septal defect, acquired | ✓ |
| I51.1 | Rupture of chordae tendineae, not elsewhere classified | ✓ |
| I51.1 | Rupture of chordae tendineae, not elsewhere classified | ✓ |
| I51.2 | Rupture of papillary muscle, not elsewhere classified | ✓ |
| I51.2 | Rupture of papillary muscle, not elsewhere classified | ✓ |
| I51.3 | Intracardiac thrombosis, not elsewhere classified | ✓ |
| I51.3 | Intracardiac thrombosis, not elsewhere classified | ✓ |
| I51.4 | Myocarditis, unspecified | ✓ |
| I51.4 | Myocarditis, unspecified | ✓ |
| I51.5 | Myocardial degeneration | ✓ |
| I51.5 | Myocardial degeneration | ✓ |
| I51.7 | Cardiomegaly | ✓ |
| I51.7 | Cardiomegaly | ✓ |
| I51.8 | Other ill-defined heart diseases | — |
| I51.8 | Other ill-defined heart diseases | — |
| I51.9 | Heart disease, unspecified | ✓ |
| I51.9 | Heart disease, unspecified | ✓ |
| I51.81 | Takotsubo syndrome | ✓ |
| I51.81 | Takotsubo syndrome | ✓ |
| I51.89 | Other ill-defined heart diseases | ✓ |
| I51.89 | Other ill-defined heart diseases | ✓ |
Frequently asked questions
What is ICD-10-CM code I51?
I51 is an ICD-10-CM category covering Complications and ill-defined descriptions of heart disease. It contains 22 more specific diagnosis codes, 20 of which are billable.
Is I51 a billable code?
No — I51 is a category header and isn't billable on its own. Code to the highest level of specificity using one of its subcodes (for example I51.0 — Cardiac septal defect, acquired). 20 of the 22 codes under I51 are billable.
What codes fall under I51?
I51 includes I51.0, I51.0, I51.1, I51.1, I51.2, plus 17 more. See the full list with descriptions and billable status above.
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Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.
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