2026 ICD-10-CM Diagnosis Code I70.90Unspecified atherosclerosis

ICD-10-CM Codes›I00–I99›I70-I79›I70

ICD-10-CM I70.90
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I70.90 is a billable ICD-10-CM diagnosis code for unspecified atherosclerosis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) 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.

Code Identity

ICD-10-CM Code
I70.90
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified atherosclerosis
Short Description
Unspecified atherosclerosis
Same as the full description in the CMS dataset.
Parent Code
I70.9
Other and unspecified atherosclerosis

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI70-I79Diseases of arteries, arterioles and capillaries
CategoryI70Atherosclerosis
This CodeI70.90Unspecified atherosclerosis

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I70.90.

Adult diagnoses
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).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal diffuse intimal thickening of artery
  • Acute occlusion of artery
  • Arteriosclerosis obliterans
  • Arteriosclerotic vascular disease
  • Arteriovascular degeneration
  • Asymptomatic chronic arterial occlusive disease
  • Asymptomatic occlusion of artery
  • Atheroma of artery
  • Atherosclerosis of artery
  • Atherosclerosis, deafness, diabetes, epilepsy, nephropathy syndrome
  • Atherosclerotic occlusive disease
  • Atherosclerotic plaque disruption with thrombosis of artery
  • Calciphylaxis
  • Condition of arterial wall - finding
  • Endarteritis
  • Endarteritis deformans
  • Endarteritis obliterans
  • Hardened arteries
  • Ischemic ulcer of lower leg due to atherosclerotic disease
  • Multifocal atherosclerosis
  • Non-uremic calcific arteriolopathy
  • Occlusion of artery
  • Senile arteriosclerosis
  • Senile arteritis
  • Senile endarteritis
  • Vascular degeneration

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Arteriosclerosis, arteriosclerotic(diffuse) (obliterans) (of) (senile) (with calcification)
    • Atheroma, atheromatous
    • Failure, failed
      • heart (acute) (senile) (sudden)
        • arteriosclerotic
    • Fibrosis, fibrotic
      • capillary

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.

  • Coronary Artery Disease

    pathological processes of coronary arteries that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.

  • Intracranial Arteriosclerosis

    vascular diseases characterized by thickening and hardening of the walls of arteries inside the skull. there are three subtypes: (1) atherosclerosis with fatty deposits in the arterial intima; (2) monckeberg's sclerosis with calcium deposits in the media and (3) arteriolosclerosis involving the small caliber arteries. clinical signs include headache; confusion; transient blindness (amaurosis fugax); speech impairment; and hemiparesis.

  • Calciphylaxis

    condition of induced systemic hypersensitivity in which tissues respond to appropriate challenging agents with a sudden local calcification.

  • Endarteritis

    inflammation of the inner endothelial lining (tunica intima) of an artery.

  • Arteriosclerosis Obliterans

    common occlusive arterial disease which is caused by atherosclerosis. it is characterized by lesions in the innermost layer (arterial intima) of arteries including the aorta and its branches to the extremities. risk factors include smoking, hyperlipidemia, and hypertension.

  • Tunica Intima

    the innermost layer of an artery or vein, made up of one layer of endothelial cells and supported by an internal elastic lamina.

  • Calciphylaxis

    a rare syndrome characterized by vascular calcification and skin necrosis. it seen in patients with end stage renal disease.

  • Endarteritis

    inflammation of 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 I70.90 to ICD-9-CMHistory

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

ICD-9-CM
440.9 Atherosclerosis 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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I70.90Overview

Is I70.90 (Other and unspecified atherosclerosis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified atherosclerosis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I70.90 group to?

When unspecified atherosclerosis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 299, 300, 301, with relative weights from 0.7197 to 1.6327 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can I70.90 be reported for?

The Medicare Code Editor checks unspecified atherosclerosis against patient demographics: this code is intended for adult patients (age 15 through 124). Claims outside these limits are flagged as inconsistent.

What is the ICD-9 equivalent of I70.90?

Under the General Equivalence Mappings, unspecified atherosclerosis converts to ICD-9-CM 440.9 (atherosclerosis NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.