2026 ICD-10-CM Diagnosis Code I82.521Chronic embolism and thrombosis of right iliac vein

ICD-10-CM Codes›I00–I99›I80-I89›I82

ICD-10-CM I82.521
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I82.521 is a billable ICD-10-CM diagnosis code for chronic embolism and thrombosis of right iliac vein. 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. Coders also document this condition as chronic deep vein thrombosis of pelvic vein. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Chronic phlebitis; thrombophlebitis and thromboembolism.

Code Identity

ICD-10-CM Code
I82.521
Billable Status
Yes — Valid for Submission
Code Describes
Chronic embolism and thrombosis of right iliac vein
Short Description
Chronic embolism and thrombosis of right iliac vein
Same as the full description in the CMS dataset.
Parent Code
I82.52
Chronic embolism and thrombosis of iliac vein

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI80-I89Diseases of veins, lymphatic vessels and lymph nodes, not elsewhere classified
CategoryI82Other venous embolism and thrombosis
This CodeI82.521Chronic embolism and thrombosis of right iliac vein

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic deep vein thrombosis of pelvic vein
  • Chronic deep vein thrombosis of right iliac vein
  • Chronic deep vein thrombosis of right pelvic vein
  • Chronic deep venous thrombosis of iliofemoral vein

Clinical ClassificationClinical

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

CCSR CIR034
Chronic phlebitis; thrombophlebitis and thromboembolism
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Deep Vein Thrombosis

Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most deep vein clots occur in the lower leg or thigh. If the vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem in the lung, called a pulmonary embolism.

Read the full article at MedlinePlus

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

Convert I82.521 to ICD-9-CMHistory

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

ICD-9-CM
453.51 Ch DVT/embl prox low ext
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 I82.521Overview

Is I82.521 (Chronic embolism and thrombosis of iliac vein) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chronic embolism and thrombosis of right iliac vein on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I82.521 group to?

When chronic embolism and thrombosis of right iliac vein 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.

What is the ICD-9 equivalent of I82.521?

Under the General Equivalence Mappings, chronic embolism and thrombosis of right iliac vein converts to ICD-9-CM 453.51 (ch DVT/embl prox low ext). 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.