ICD-10 Code I79 – Disorders of arteries, arterioles and capillaries in diseases classified elsewhere (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I79 – Disorders of arteries, arterioles and capillaries in diseases classified elsewhere
What it is
I79 identifies arterial, arteriolar, or capillary disorders that are caused by another underlying disease. Use it when the vascular problem is secondary and the primary condition is documented elsewhere.
Clinical signs
Clinical features vary; refer to documentation. Findings may include signs of impaired circulation in small or large vessels, but you should code only when the record links the vascular disorder to a separate disease.
When to use this code
Use I79 when the provider states that the artery, arteriole, or capillary disorder is due to another classified condition. This code supports secondary vascular involvement rather than a primary vascular diagnosis. Confirm the underlying disease and any site-specific vascular description in the note.
Do not use for
Do not use I79 for a primary vascular disorder without an identified cause. If the documentation does not clearly connect the vascular finding to another disease, check documentation and consider a more specific code.
Coding tip
Always sequence the underlying disease first when it is the reason for the vascular disorder, unless coding guidance says otherwise.