2026 ICD-10-CM Diagnosis Code I28.9Disease of pulmonary vessels, unspecified

ICD-10-CM Codes›I00–I99›I26-I28›I28

ICD-10-CM I28.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I28.9 is a billable ICD-10-CM diagnosis code for disease of pulmonary vessels, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316. Coders also document this condition as acquired abnormality of pulmonary arterial tree. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pulmonary heart disease.

Code Identity

ICD-10-CM Code
I28.9
Billable Status
Yes — Valid for Submission
Code Describes
Disease of pulmonary vessels, unspecified
Short Description
Disease of pulmonary vessels, unspecified
Same as the full description in the CMS dataset.
Parent Code
I28
Other diseases of pulmonary vessels

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI26-I28Pulmonary heart disease and diseases of pulmonary circulation
CategoryI28Other diseases of pulmonary vessels
This CodeI28.9Disease of pulmonary vessels, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acquired abnormality of pulmonary arterial tree
  • Disorder of pulmonary circulation
  • Peripheral pulmonary artery disease
  • Pulmonary arterial tree abnormality as complication of procedure
  • Pulmonary vein abnormality as complication of procedure

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.

    • Disease, diseased
      • pulmonary
        • artery

Clinical ClassificationClinical

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

CCSR CIR014
Pulmonary heart disease
Default principal diagnosis: inpatient Yes · outpatient Yes

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 I28.9 to ICD-9-CMHistory

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

ICD-9-CM
417.9 Pulmon circulat dis 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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I28.9Overview

Is I28.9 (Other diseases of pulmonary vessels) a billable code?

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

What MS-DRG does I28.9 group to?

When disease of pulmonary vessels, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 314, 315, 316, with relative weights from 0.6821 to 2.0852 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of I28.9?

Under the General Equivalence Mappings, disease of pulmonary vessels, unspecified converts to ICD-9-CM 417.9 (pulmon circulat dis NOS). The mapping is a direct match.

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.