ICD-10 Code I70.509 – Unspecified atherosclerosis of nonautologous biological bypass graft(s) of the extremities, unspecified extremity (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I70.509 – Unspecified atherosclerosis of nonautologous biological bypass graft(s) of the extremities, unspecified extremity
What it is
This code identifies atherosclerotic narrowing or blockage in a nonautologous biological bypass graft in an extremity, when the affected limb is not specified. Use it for graft disease, not native artery disease. Check documentation.
Clinical signs
Clinical features vary; refer to documentation. Findings may include reduced graft patency, diminished distal pulses, ischemic pain, or signs of impaired limb perfusion, but the record must support graft atherosclerosis.
When to use this code
Use I70.509 when the provider documents atherosclerosis involving a biological bypass graft in an arm or leg and does not identify the specific extremity. It also fits when the graft disease is documented but laterality is unclear. If the note names a native vessel, a different code is needed.
Do not use for
Do not use this code for atherosclerosis of native arteries, occlusion without atherosclerosis, or complications of synthetic grafts. If the documentation does not clearly state a nonautologous biological bypass graft, check documentation.
Coding tip
Confirm both graft type and laterality in the operative or follow-up note before assigning I70.509.