2026 ICD-10-CM Diagnosis Code I28.8Other diseases of pulmonary vessels

ICD-10-CM Codes›I00–I99›I26-I28›I28

ICD-10-CM I28.8
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I28.8 is a billable ICD-10-CM diagnosis code for other diseases of pulmonary vessels. 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pulmonary heart disease.

For Medicare Advantage risk adjustment, I28.8 maps to CMS-HCC Category 226 (Heart Failure, Except End Stage and Acute) under the V28 model, adding a risk factor of about 0.360 for a community, non-dual, aged beneficiary in payment year 2026.

Code Identity

ICD-10-CM Code
I28.8
Billable Status
Yes — Valid for Submission
Code Describes
Other diseases of pulmonary vessels
Short Description
Other diseases of pulmonary vessels
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 CodeI28.8Other diseases of pulmonary vessels

Medicare Risk Adjustment (HCC)Billing

I28.8 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 2026.

CMS-HCC V28 Category (Payment Model)
HCC 226— Heart Failure, Except End Stage and Acute
Payment HCC · PY 2026 one of 34 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.360
community, non-dual, aged · ranges 0.217–0.537 across segments
Hierarchy
Superseded by HCC 221, HCC 222, HCC 223, HCC 224, and HCC 225
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 85
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 85 · ESRD (V21): HCC 85 · ESRD (V24): HCC 85
ESRD V21 weights: 0.082 dialysis, 0.186–0.336 functioning graft · ESRD V24 weights: 0.063 dialysis, 0.169–0.302 functioning graft
Part D (RxHCC)
RxHCC 184 — Pulmonary Hypertension, Except Arterial, and Other Pulmonary Heart Disease
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2026 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.

  • Acquired abnormality of pulmonary venous structure
  • Acquired discontinuity of pulmonary arteries
  • Acquired obstruction of systemic to pulmonary arterial shunt due to and following procedure
  • Acquired pulmonary trunk stenosis
  • Acquired pulmonary venous obstruction
  • Acquired stenosis of left pulmonary artery
  • Acquired stenosis of pulmonary venous structure
  • Acquired stenosis of right pulmonary artery
  • Arteriovenous malformation of pulmonary vessels following cavopulmonary anastomosis
  • Diffuse stenosis of left pulmonary artery
  • Diffuse stenosis of right pulmonary artery
  • Dilatation of pulmonary artery
  • Endarteritis
  • Hypoperfusion of left pulmonary artery due to preferential flow to right pulmonary artery
  • Hypoperfusion of right pulmonary artery due to preferential flow to left pulmonary artery
  • Injury of pulmonary artery
  • Multiple peripheral pulmonary artery stenoses
  • Multiple stenoses of left pulmonary artery
  • Multiple stenoses of right pulmonary artery
  • Obstructed pulmonary venous connection
  • Obstructed pulmonary venous connection at interatrial communication
  • Obstructed pulmonary venous connection due to extrinsic compression
  • Obstructed pulmonary venous connection due to extrinsic compression at diaphragm
  • Obstructed pulmonary venous connection due to extrinsic compression between left pulmonary artery and bronchus
  • Obstructed pulmonary venous connection due to extrinsic compression between right pulmonary artery and trachea
  • Obstructed pulmonary venous connection due to intrinsic narrowing
  • Obstruction of pulmonary great vein due to compression by right atrial dilatation
  • Obstruction of pulmonary outflow tract
  • Obstruction of pulmonary vein as complication of procedure
  • Peripheral pulmonary artery disease
  • Peripheral pulmonary artery stenosis
  • Postoperative stenosis of pulmonary vein
  • Pulmonary arteriovenous malformation
  • Pulmonary arteritis
  • Pulmonary artery aneurysm
  • Pulmonary artery rupture
  • Pulmonary blood vessel injury
  • Pulmonary endarteritis
  • Pulmonary hypertension secondary to raised pulmonary vascular resistance
  • Pulmonary trunk stenosis
  • Pulmonary trunk stenosis as complication of procedure
  • Pulmonary vein abnormality as complication of procedure
  • Pulmonary vein dilatation
  • Pulmonary vein stenosis
  • Rupture of pulmonary artery co-occurrent and due to aneurysm of pulmonary artery
  • Rupture of pulmonary vessel
  • Single stenosis of left pulmonary artery
  • Single stenosis of right pulmonary artery
  • Stenosis of anastomosis between pulmonary venous confluence and left atrium after prior repair of anomalous pulmonary venous connection
  • Stenosis of left pulmonary artery
  • Stenosis of left pulmonary artery as complication of procedure
  • Stenosis of pulmonary great vein as complication of procedure
  • Stenosis of right pulmonary artery
  • Stenosis of right pulmonary artery as complication of procedure
  • Stricture of pulmonary vessel
  • Supravalvar pulmonary trunk stenosis
  • Tortuosity of pulmonary artery

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Pulmonary arteritis
  • Pulmonary endarteritis
  • Rupture of pulmonary vessels
  • Stenosis of pulmonary vessels
  • Stricture of pulmonary vessels

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

Clinical InformationClinical

  • Endarteritis

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

  • 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.

  • Pulmonary Vein Stenosis

    obstruction of the pulmonary vein in one or multiple sites. the obstruction is the result of wall thickening and narrowing of the lumen of the vein.

  • Endarteritis

    inflammation of the arterial intima.

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?
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Read the full article at MedlinePlus

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

Convert I28.8 to ICD-9-CMHistory

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

ICD-9-CM
417.8 Pulmon circulat dis NEC
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 I28.8Overview

What is the ICD-10 code for other diseases of pulmonary vessels?

The ICD-10-CM code for other diseases of pulmonary vessels is I28.8 (sometimes written as I288). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is I28.8 (Other diseases of pulmonary vessels) a billable code?

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

What MS-DRG does I28.8 group to?

When other diseases of pulmonary vessels 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 I28.8?

Under the General Equivalence Mappings, other diseases of pulmonary vessels converts to ICD-9-CM 417.8 (pulmon circulat dis NEC). The mapping is a direct match.

What HCC is I28.8?

I28.8 (other diseases of pulmonary vessels) maps to CMS-HCC Category 226 (Heart Failure, Except End Stage and Acute), commonly written as HCC 226, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 85 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 184.

Does I28.8 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, I28.8 adds a risk adjustment factor of about 0.360 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.217 to 0.537 depending on the payment segment). A more severe related category (HCC 221, HCC 222, HCC 223, HCC 224, and HCC 225) supersedes it when both are reported. See the full factor table on the HCC 226 category page.