ICD-10 Code I70.642 – Atherosclerosis of nonbiological bypass graft(s) of the left leg with ulceration of calf (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I70.642 – Atherosclerosis of nonbiological bypass graft(s) of the left leg with ulceration of calf
What it is
This code identifies atherosclerotic narrowing or blockage in a nonbiological bypass graft in the left leg, with an associated ulcer on the calf. Use it when the graft disease and ulcer are both documented.
Clinical signs
Clinical features may include reduced limb blood flow, pain, skin breakdown, or a nonhealing calf ulcer. Clinical features vary; refer to documentation for graft type, laterality, and ulcer location.
When to use this code
Use this code when the record states atherosclerosis affects a nonbiological bypass graft in the left leg and the ulcer is on the calf. You should confirm both the graft location and the ulcer site in the provider note. If the ulcer type or laterality is unclear, check documentation before coding.
Do not use for
Do not use this code for native vessel peripheral arterial disease without a bypass graft, or for ulcers not linked to the documented graft disease. Check documentation if the graft material, leg side, or ulcer site is missing.
Coding tip
Verify that “nonbiological bypass graft” and “left leg calf ulceration” are both explicitly documented before assigning I70.642.