2027 ICD-10-CM Diagnosis Code I70.621Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg

ICD-10-CM Codes›I00–I99›I70-I79›I70

ICD-10-CM I70.621
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I70.621 is a billable ICD-10-CM diagnosis code for atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 299 through 301. The code is restricted by the Medicare Code Editor to adult patients (age 15 through 124). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Peripheral and visceral vascular disease.

For Medicare Advantage risk adjustment, I70.621 maps to CMS-HCC Category 264 (Vascular Disease with Complications) under the V28 model, adding a risk factor of about 0.455 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
I70.621
Billable Status
Yes — Valid for Submission
Code Describes
Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg
Short Description
Athscl nonbiol bypass of the extrm w rest pain, right leg
Parent Code
Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI70-I79Diseases of arteries, arterioles and capillaries
CategoryI70Atherosclerosis
This CodeI70.621Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I70.621.

The Medicare Code Editor detects inconsistencies in adult cases by checking a patient's age and any diagnosis on the patient's record. The adult code edits apply to patients age range is 15–124 years inclusive (e.g., senile delirium, mature cataract).

Medicare Risk Adjustment (HCC)Billing

I70.621 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 264— Vascular Disease with Complications
Payment HCC · PY 2027 one of 71 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.455
community, non-dual, aged · ranges 0.338–0.622 across segments
Hierarchy
Superseded by HCC 263
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 108
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 108 · ESRD (V21): HCC 108 · ESRD (V24): HCC 108
ESRD V21 weights: 0.065 dialysis, 0.086–0.271 functioning graft · ESRD V24 weights: 0.073 dialysis, 0.074–0.287 functioning graft
Part D (RxHCC)
Not mapped
I70.621 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I70.621: its own notes plus those printed at I70.62, I70.6, I70, and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From I70.62 Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain applies to 5 codes
  • any condition classifiable to I70.61-
  • chronic limb-threatening ischemia NOS of nonbiological bypass graft(s) of the extremities
  • chronic limb-threatening ischemia of nonbiological bypass graft(s) of the extremities with rest pain
  • critical limb ischemia NOS of nonbiological bypass graft(s) of the extremities
  • critical limb ischemia of nonbiological bypass graft(s) of the extremities with rest pain
From I70 Atherosclerosis applies to 246 codes
  • arteriolosclerosis
  • arterial degeneration
  • arteriosclerosis
  • arteriosclerotic vascular disease
  • arteriovascular degeneration
  • atheroma
  • endarteritis deformans or obliterans
  • senile arteritis
  • senile endarteritis
  • vascular degeneration

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From I70 Atherosclerosis applies to 246 codes
  • arteriosclerotic cardiovascular disease (I25.1-)
  • arteriosclerotic heart disease (I25.1-)
  • atheroembolism (I75.-)
  • cerebral atherosclerosis (I67.2)
  • coronary atherosclerosis (I25.1-)
  • mesenteric atherosclerosis (K55.1)
  • precerebral atherosclerosis (I67.2)
  • primary pulmonary atherosclerosis (I27.0)
From Chapter 9 (I00-I99) Diseases of the circulatory system applies to 1,433 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • transient cerebral ischemic attacks and related syndromes (G45.-)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From I70.6 Atherosclerosis of nonbiological bypass graft(s) of the extremities applies to 40 codes
  • code, if applicable, to identify chronic total occlusion of artery of extremity (I70.92)
From I70 Atherosclerosis applies to 246 codes
  • code to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name I70.621, its category, or a range that includes it.

Includes 2

These notes mention I70.621.

  • I70.63 Atherosclerosis of nonbiological bypass graft(s) of the right leg with ulceration
    any condition classifiable to I70.611 and I70.621
  • I70.66 Atherosclerosis of nonbiological bypass graft(s) of the extremities with gangrene
    any condition classifiable to I70.61-, I70.62-, I70.63-, I70.64-, I70.65 names I70.62-, which includes this code

Excludes1 3

These codes carry an Excludes1 note naming I70.621: they are not reported together with it, unless the two conditions are unrelated.

  • I77.6 Arteritis, unspecified
    deformans (I70.-) names I70.-, which includes this code
  • I77.6 Arteritis, unspecified
    obliterans (I70.-) names I70.-, which includes this code
  • I77.6 Arteritis, unspecified
    senile (I70.-) names I70.-, which includes this code

Code First 1

These codes say to code first a condition named in the note, and I70.621 is one of the conditions named.

  • I70.92 Chronic total occlusion of artery of the extremities
    atherosclerosis of arteries of the extremities (I70.2-, I70.3-, I70.4-, I70.5-, I70.6-, I70.7-) names I70.6-, which includes this code

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR CIR026
Peripheral and visceral vascular disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Atherosclerosis

    a thickening and loss of elasticity of the walls of arteries that occurs with formation of atherosclerotic plaques within the arterial intima.

Patient EducationClinical

Atherosclerosis

Atherosclerosis is a condition in which plaque builds up inside your arteries. Plaque is a sticky substance made up of cholesterol, fat, blood cells, calcium, and other substances found in the blood. Over time, plaque hardens and causes your arteries to narrow. That limits the flow of oxygen-rich blood to your body.

The full article covers:

  • What is atherosclerosis?
  • What causes atherosclerosis?
  • Who is more likely to develop atherosclerosis?
  • What are the symptoms of atherosclerosis?
  • What other problems can atherosclerosis cause?
  • How is atherosclerosis diagnosed?
  • What are the treatments for atherosclerosis?
  • Can atherosclerosis be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert I70.621 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
440.30 Athscl extrm bps gft NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I70.621Overview

Is I70.621 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I70.621 group to?

When atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg is the principal diagnosis on an inpatient stay, it groups to MS-DRG 301, 300, 299, with relative weights from 0.7132 to 1.5840 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can I70.621 be reported for?

The Medicare Code Editor checks atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg against patient demographics: this code is intended for adult patients (age 15 through 124). Claims outside these limits are flagged as inconsistent.

Does I70.621 need an additional code?

When the condition applies, yes. The Use Additional Code note at I70.6, which applies to I70.621, reads: code, if applicable, to identify chronic total occlusion of artery of extremity (I70.92). The additional code is reported after I70.621.

What is the ICD-9 equivalent of I70.621?

Under the General Equivalence Mappings, atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg converts to ICD-9-CM 440.30 (athscl extrm bps gft NOS). The mapping is approximate, so confirm the match fits the documentation.

What HCC is I70.621?

I70.621 (atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, right leg) maps to CMS-HCC Category 264 (Vascular Disease with Complications), commonly written as HCC 264, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 108 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does I70.621 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, I70.621 adds a risk adjustment factor of about 0.455 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.338 to 0.622 depending on the payment segment). A more severe related category (HCC 263) supersedes it when both are reported. See the full factor table on the HCC 264 category page.