MCMCB Pro
I49.8

I49.8Other specified cardiac arrhythmias

Billable / specific codeICD-10-CM

I49.8 is a billable, specific ICD-10-CM code for other specified cardiac arrhythmias. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Brugada syndrome
  • Coronary sinus rhythm disorder
  • Ectopic rhythm disorder
  • Nodal rhythm disorder

Risk adjustment

I49.8 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

I49.8 is named in 30 Medicare coverage policies 30 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A56423Billing and Coding: Cardiology Non-emergent Outpatient Stress Testing
  • A56423Billing and Coding: Cardiology Non-emergent Outpatient Stress Testing
  • A56423Billing and Coding: Cardiology Non-emergent Outpatient Stress Testing
  • A56423Billing and Coding: Cardiology Non-emergent Outpatient Stress Testing

How I49.8 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to I49.8.

  • Bradyarrhythmia, cardiac
  • Nodal rhythm
  • Arrhythmiasinus
  • Arrhythmiaspecified NEC
  • Fibrillationcardiac
  • Fibrillationheart
  • Flutterheart
  • Rhythmatrioventricular nodal
  • Rhythmnodal
  • Sinusarrhythmia
  • SyndromeBrugada
  • Wanderingpacemaker(heart)

Related codes at this level

Codes that share I49. If I49.8 is not quite right, the correct code is usually one of these.

Questions about I49.8

Is I49.8 a billable ICD-10-CM code?
Yes. I49.8 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does I49.8 sit in the tabular list?
Diseases of the circulatory system (I00-I99), in the block Other forms of heart disease (I30-I5A).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.