2027 ICD-10-CM Diagnosis Code I49.81Brugada syndrome

ICD-10-CM Codes›I00–I99›I30-I5A›I49

ICD-10-CM I49.81
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I49.81 is a billable ICD-10-CM diagnosis code for brugada syndrome. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 308 through 310. Coders also document this condition as acquired Brugada syndrome.

Code Identity

ICD-10-CM Code
I49.81
Billable Status
Yes — Valid for Submission
Code Describes
Brugada syndrome
Short Description
Brugada syndrome
Same as the full description in the CMS dataset.
Parent Code
I49.8
Other specified cardiac arrhythmias

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI30-I5AOther forms of heart disease
CategoryI49Other cardiac arrhythmias
This CodeI49.81Brugada syndrome

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acquired Brugada syndrome
  • Brugada syndrome

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I49.81: its own notes plus those printed at I49 and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

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 I49 Other cardiac arrhythmias applies to 12 codes
  • bradycardia NOS (R00.1)
  • neonatal dysrhythmia (P29.1-)
  • sinoatrial bradycardia (R00.1)
  • sinus bradycardia (R00.1)
  • vagal bradycardia (R00.1)
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 I49 Other cardiac arrhythmias applies to 12 codes
  • cardiac arrhythmia complicating:
  • abortion or ectopic or molar pregnancy (O00-O07, O08.8)
  • obstetric surgery and procedures (O75.4)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name I49.81, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming I49.81: its condition is not part of those codes, and both may be reported when the patient has both.

  • R00 Abnormalities of heart beat
    specified arrhythmias (I47-I49) names I47-I49, which includes this code

Code Also 1

These codes say I49.81 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • M35.81 Multisystem inflammatory syndrome
    cardiac arrhythmia (I47-I49.-) names I47-I49, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical InformationClinical

  • Brugada Syndrome

    an autosomal dominant defect of cardiac conduction that is characterized by an abnormal st-segment in leads v1-v3 on the electrocardiogram resembling a right bundle-branch block; high risk of ventricular tachycardia; or ventricular fibrillation; syncopal episode; and possible sudden death. this syndrome is linked to mutations of gene encoding the cardiac sodium channel alpha subunit.

Code History & ChangesHistory

New Code I49.81 was added to the ICD-10-CM code set for FY 2027, effective October 1, 2026.

Replacement I49.81 replaces the following previously assigned code(s):

  • I49.8 - Other specified cardiac arrhythmias
FY 2027AddedAdded to the ICD-10-CM code setEffective October 1, 2026.
FY 2027CurrentRevised in the current code setEffective October 1, 2026 through September 30, 2027.

Questions About I49.81Overview

What is the ICD-10 code for brugada syndrome?

The ICD-10-CM code for brugada syndrome is I49.81 (sometimes written as I4981). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is I49.81 (Other specified cardiac arrhythmias) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report brugada syndrome on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I49.81 group to?

When brugada syndrome is the principal diagnosis on an inpatient stay, it groups to MS-DRG 309, 310, 308, with relative weights from 0.5686 to 1.1809 depending on complications. Higher weights mean higher Medicare reimbursement.

What is coded first with I49.81?

The Code First note at I49, which applies to I49.81, reads: cardiac arrhythmia complicating: abortion or ectopic or molar pregnancy (O00-O07, O08.8); obstetric surgery and procedures (O75.4). When one of these applies, it is sequenced before I49.81.