2026 ICD-10-CM Diagnosis Code R00Abnormalities of heart beat

ICD-10-CM CodesR00–R99R00-R09R00

ICD-10-CM R00
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R00 is a non-billable ICD-10-CM category code for abnormalities of heart beat, so it cannot be submitted on claims. Use a more specific code from this category instead, such as R00.0, R00.1, R00.2, and R00.8. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established.

This medical diagnosis code is frequently used in Cardiology medical specialties to designate conditions such abnormalities of heart rhythm.

Code Identity

ICD-10-CM Code
R00
Billable Status
No — Non-Billable Category
Code Describes
Abnormalities of heart beat
Short Description
Abnormalities of heart beat
Same as the full description in the CMS dataset.
Chapter
R00-R09
Symptoms and signs involving the circulatory and respiratory systems

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR00-R09Symptoms and signs involving the circulatory and respiratory systems
CategoryR00Abnormalities of heart beat
This CodeR00Abnormalities of heart beat

Specific Coding for Abnormalities of heart beatOverview

Non-specific codes like R00 require more characters. Use one of these billable codes instead:

  • Use R00.0 for Tachycardia, unspecified

  • Use R00.1 for Bradycardia, unspecified

  • Use R00.2 for Palpitations

  • Use R00.8 for Other abnormalities of heart beat

  • Use R00.9 for Unspecified abnormalities of heart beat

Tabular List NotesGuidance

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

Type 1 Excludes

  • abnormalities originating in the perinatal period P29.1

Type 2 Excludes

  • specified arrhythmias I47 I49

Patient EducationClinical

Arrhythmia

An arrhythmia is a problem with the rate or rhythm of your heartbeat. Your heart beats too quickly, too slowly, or with an irregular pattern. Changes in the electrical signals that control your heartbeat cause arrhythmias.

The full article covers:

  • What is an arrhythmia?
  • What causes an arrhythmia?
  • What are the symptoms of an arrhythmia?
  • How is an arrhythmia diagnosed?
  • What are the treatments for an arrhythmia?
  • Can arrhythmias be prevented?

Read the full article at MedlinePlus

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

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 R00Overview

Is R00 (Abnormalities of heart beat) a billable code?

No. This is a category header that groups the codes for abnormalities of heart beat, and headers cannot be submitted on claims. Claims for abnormalities of heart beat need a more specific code from this category, such as R00.0, R00.1, and R00.2.

Can R00 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the abnormalities of heart beat is established, that condition takes the principal position instead.