When is ICD-10 code I70.66 used?

Doctors, hospitals, and insurers may use ICD-10 code I70.66 when recording atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene in a standardized format. This entry may also act as a broader category that points toward more specific child codes.

Does ICD-10 code I70.66 confirm a diagnosis?

No. A code helps standardize documentation and claims, but it should not be read as a substitute for a clinician's full assessment.

ICD10

ICD-10 Code I70.66: Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene

Name: ICD-10 Code I70.66: Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene
Creator: HealthAssure Clinical Team
Published: 2026-05-21T06:13:47.346Z

I70.66 is an ICD-10 diagnosis entry used to group records related to Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the circulatory system (I00-I99).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the circulatory system (I00-I99).

When is it used?

May be used when a clinician documents atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene in a patient's medical record.
May appear in hospital records, claims, referrals, and clinical documentation.
This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

A code alone does not explain severity, treatment plan, or outcome.
A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter

9Diseases of the circulatory system (I00-I99)

block

I70-I79Diseases of arteries, arterioles and capillaries

Official coding notes

Includes

any condition classifiable to I70.61-, I70.62-, I70.63-, I70.64-, I70.65
chronic limb-threatening ischemia of nonbiological bypass graft(s) of the extremities with gangrene
critical limb ischemia of nonbiological bypass graft(s) of the extremities with gangrene

Applicable to

code to identify the severity of any ulcer (L97.-, L98.49-), if applicable

Use additional code

code to identify the severity of any ulcer (L97.-, L98.49-), if applicable

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

CardiologistGeneral Physician

Sibling codes

I70.60Unspecified atherosclerosis of nonbiological bypass graft(s) of the extremities I70.61Atherosclerosis of nonbiological bypass graft(s) of the extremities with intermittent claudication I70.62Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain I70.63Atherosclerosis of nonbiological bypass graft(s) of the right leg with ulceration I70.64Atherosclerosis of nonbiological bypass graft(s) of the left leg with ulceration I70.65Atherosclerosis of nonbiological bypass graft(s) of other extremity with ulcerationbillable I70.69Other atherosclerosis of nonbiological bypass graft(s) of the extremities

Coding guidelines

Common synonyms

Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangreneAtherosclerosis of nonbiological bypass graftAtherosclerosis of nonbiological bypass graft s of the extremities with gangrene

Frequently asked questions

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.