ICD-10 Code I70.66 – Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I70.66 – Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene
What it is
This code identifies atherosclerotic narrowing or blockage in a nonbiological bypass graft in an arm or leg, with gangrene present. It reflects poor blood flow through the graft and tissue death in the affected extremity.
Clinical signs
Typical findings include ischemic pain, cool skin, diminished pulses, and blackened or necrotic tissue in the limb. Clinical features vary; refer to documentation for graft type, extremity involved, and confirmation of gangrene.
When to use this code
Use this code when the record clearly documents atherosclerosis affecting a nonbiological bypass graft in an extremity and gangrene is present. The graft should be synthetic or otherwise nonbiologic, not a vein graft. If the note does not specify gangrene or graft type, check documentation.
Do not use for
Do not use this code for native artery atherosclerosis without a bypass graft, or for graft disease without gangrene. Do not assign it when the graft is biologic, or when documentation is unclear.
Coding tip
Verify both the graft material and the presence of gangrene before coding I70.66.