2027 ICD-10-CM Diagnosis Code I82.403Acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral

ICD-10-CM Codes›I00–I99›I80-I89›I82

ICD-10-CM I82.403
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I82.403 is a billable ICD-10-CM diagnosis code for acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral. 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. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 201 closely related codes. Coders also document this condition as acute deep vein thrombosis of bilateral lower limbs following coronary artery bypass graft. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Acute phlebitis; thrombophlebitis and thromboembolism.

For Medicare Advantage risk adjustment, I82.403 maps to CMS-HCC Category 267 (Deep Vein Thrombosis and Pulmonary Embolism) under the V28 model, adding a risk factor of about 0.294 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
I82.403
Billable Status
Yes — Valid for Submission
Code Describes
Acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral
Short Description
Acute embolism and thombos unsp deep veins of low extrm, bi
Parent Code
Acute embolism and thrombosis of unspecified deep veins of lower extremity

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 CodeI82.403Acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral

Medicare Risk Adjustment (HCC)Billing

I82.403 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 2027.

CMS-HCC V28 Category (Payment Model)
HCC 267— Deep Vein Thrombosis and Pulmonary Embolism
Payment HCC · PY 2027 one of 167 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.294
community, non-dual, aged · ranges 0.245–0.568 across segments
Hierarchy
Top of its hierarchy
HCC 267 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
HCC 108
V24 retired V28 pays 100% of MA risk scores since PY 2026
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)
RxHCC 215 — Venous Thromboembolism
also risk-adjusts in the Part D prescription drug model (V08)

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.

  • Acute deep vein thrombosis of bilateral lower limbs following coronary artery bypass graft
  • Acute deep vein thrombosis of bilateral lower limbs following procedure
  • Acute deep vein thrombosis of left lower limb following coronary artery bypass graft
  • Acute deep vein thrombosis of left lower limb following procedure
  • Acute deep vein thrombosis of right lower limb following coronary artery bypass graft
  • Acute deep vein thrombosis of right lower limb following procedure
  • Acute deep venous thrombosis of bilateral legs
  • Bilateral deep vein thrombosis of lower extremities

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I82.403: its own notes plus those printed at I82.40, I82, and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From I82.40 Acute embolism and thrombosis of unspecified deep veins of lower extremity applies to 4 codes
  • acute embolism and thrombosis of unspecified deep veins of distal lower extremity (I82.4Z-)
  • acute embolism and thrombosis of unspecified deep veins of proximal lower extremity (I82.4Y-)

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 I82 Other venous embolism and thrombosis applies to 145 codes
  • venous embolism and thrombosis (of):
  • cerebral (I63.6, I67.6)
  • coronary (I21-I25)
  • intracranial and intraspinal, septic or NOS (G08)
  • intracranial, nonpyogenic (I67.6)
  • intraspinal, nonpyogenic (G95.1)
  • mesenteric (K55.0-)
  • portal (I81)
  • pulmonary (I26.-)
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.-)

Code First

The underlying condition named in the note is sequenced before this code.

From I82 Other venous embolism and thrombosis applies to 145 codes
  • venous embolism and thrombosis complicating:
  • abortion, ectopic or molar pregnancy (O00-O07, O08.7)
  • pregnancy, childbirth and the puerperium (O22.-, O87.-)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name I82.403, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming I82.403: they are not reported together with it, unless the two conditions are unrelated.

  • I80 Phlebitis and thrombophlebitis
    venous embolism and thrombosis of lower extremities (I82.4-, I82.5-, I82.81-) names I82.4-, which includes this code

Use Additional Code 2

These codes say to use an additional code from the note, and I82.403 is one of the codes named.

  • O22.3 Deep phlebothrombosis in pregnancy
    code to identify the deep vein thrombosis (I82.4-, I82.5-, I82.62-, I82.72-) names I82.4-, which includes this code
  • O87.1 Deep phlebothrombosis in the puerperium
    code to identify the deep vein thrombosis (I82.4-, I82.5-, I82.62-, I82.72-) names I82.4-, which includes this code

Clinical ClassificationClinical

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

CCSR CIR033
Acute 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 I82.403 to ICD-9-CMHistory

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

ICD-9-CM
453.40 Ac DVT/embl low ext 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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I82.403Overview

Is I82.403 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I82.403 group to?

When acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral 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.

Is I82.403 a CC or MCC?

CMS lists I82.403 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 201 closely related codes in its exclusion list.

Can I82.403 be reported with a code from I82.4Z?

Not as a rule. The Excludes1 note at I82.40, which applies to I82.403, lists "acute embolism and thrombosis of unspecified deep veins of distal lower extremity (I82.4Z-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is coded first with I82.403?

The Code First note at I82, which applies to I82.403, reads: venous embolism and thrombosis complicating: abortion, ectopic or molar pregnancy (O00-O07, O08.7); pregnancy, childbirth and the puerperium (O22.-, O87.-). When one of these applies, it is sequenced before I82.403.

What HCC is I82.403?

I82.403 (acute embolism and thrombosis of unspecified deep veins of lower extremity, bilateral) maps to CMS-HCC Category 267 (Deep Vein Thrombosis and Pulmonary Embolism), commonly written as HCC 267, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 108 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 215.

Does I82.403 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, I82.403 adds a risk adjustment factor of about 0.294 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.245 to 0.568 depending on the payment segment). HCC 267 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 267 category page.