2027 ICD-10-CM Diagnosis Code I77.9Disorder of arteries and arterioles, unspecified

ICD-10-CM Codes›I00–I99›I70-I79›I77

ICD-10-CM I77.9
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I77.9 is a billable ICD-10-CM diagnosis code for disorder of arteries and arterioles, unspecified. 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified circulatory disease.

I77.9 no longer risk-adjusts for Medicare Advantage: it mapped to HCC 108 under the retired CMS-HCC V24 model through payment year 2025 but maps to no category in the live V28 model. It still risk-adjusts in the PACE (CMS-HCC V22) category 108, ESRD (V21) category 108, and ESRD (V24) category 108 for payment year 2027.

Code Identity

ICD-10-CM Code
I77.9
Billable Status
Yes — Valid for Submission
Code Describes
Disorder of arteries and arterioles, unspecified
Short Description
Disorder of arteries and arterioles, unspecified
Same as the full description in the CMS dataset.
Parent Code
I77
Other disorders of arteries and arterioles

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI70-I79Diseases of arteries, arterioles and capillaries
CategoryI77Other disorders of arteries and arterioles
This CodeI77.9Disorder of arteries and arterioles, unspecified

Medicare Risk Adjustment (HCC)Billing

I77.9 no longer risk-adjusts for Medicare Advantage: it maps to no payment category in the live CMS-HCC V28 model, although it still risk-adjusts in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
Dropped in V28 see all codes that no longer risk-adjust
Prior Model (CMS-HCC V24)
HCC 108
V24 retired last contributed to a Medicare Advantage risk score in payment year 2025
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
I77.9 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.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormality of abdominal aorta
  • Abnormality of thoracoabdominal aorta
  • Acquired abnormality of aorta due to congenital heart anomaly
  • Arterial complication of procedure
  • Ascending aorta abnormality
  • Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
  • Complication of arterial duct due to and following procedure
  • Disease of non-coronary systemic artery
  • Disorder of aorta
  • Disorder of aorta due to and following correction of congenital heart anomaly
  • Disorder of aortic arch and descending aorta
  • Disorder of arteriole
  • Disorder of artery
  • Disorder of artery caused by ionizing radiation
  • Disorder of artery of neck
  • Disorder of carotid artery
  • Disorder of coronary artery
  • Disorder of thoracic aorta
  • Erectile dysfunction due to disorder of artery
  • Erectile dysfunction due to disorder of blood vessel
  • Ischemia of feet
  • Ischemic foot
  • Lower limb ischemia
  • Peripheral arterial occlusive disease
  • Trash foot
  • White matter disorder co-occurrent and due to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I77.9: its own notes plus those printed at I77 and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

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 I77 Other disorders of arteries and arterioles applies to 23 codes
  • collagen (vascular) diseases (M30-M36)
  • hypersensitivity angiitis (M31.0)
  • pulmonary artery (I28.-)
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.-)

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

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR CIR032
Other specified and unspecified circulatory disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Arterial Disorder

    an impairment of the structure or function of the blood vessels which carry blood away from the heart.

Patient EducationClinical

Vascular Diseases

Your vascular system is your body's network of blood vessels. It includes your:

The full article covers:

  • What are vascular diseases?
  • What causes vascular diseases?
  • Who is at risk for vascular diseases?
  • What are the symptoms of vascular diseases?
  • How are vascular diseases diagnosed?
  • How are vascular diseases treated?
  • Can vascular diseases be prevented?

Read the full article at MedlinePlus

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

Convert I77.9 to ICD-9-CMHistory

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

ICD-9-CM
447.9 Arterial disease NOS
Exact Match The mapping is direct, with no qualifiers.

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 I77.9Overview

What is the ICD-10 code for disorder of arteries and arterioles, unspecified?

The ICD-10-CM code for disorder of arteries and arterioles, unspecified is I77.9 (sometimes written as I779). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is I77.9 (Other disorders of arteries and arterioles) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report disorder of arteries and arterioles, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I77.9 group to?

When disorder of arteries and arterioles, unspecified 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.

What is the ICD-9 equivalent of I77.9?

Under the General Equivalence Mappings, disorder of arteries and arterioles, unspecified converts to ICD-9-CM 447.9 (arterial disease NOS). The mapping is a direct match.

Does I77.9 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage. I77.9 mapped to HCC 108 in the retired CMS-HCC V24 model, which last determined payment in 2025, but it maps to no category in the live V28 model; see all codes that no longer risk-adjust. It still risk-adjusts in the PACE (CMS-HCC V22) category 108 (Vascular Disease), ESRD (V21) category 108 (Vascular Disease), and ESRD (V24) category 108 (Vascular Disease).