ICD-10-CM Code I45.10

Unspecified right bundle-branch block

Version 2020 Billable Code Questionable Admission Codes

Valid for Submission

I45.10 is a billable code used to specify a medical diagnosis of unspecified right bundle-branch block. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code I45.10 might also be used to specify conditions or terms like bifascicular block, bifascicular block on electrocardiogram, ekg: complete right bundle branch block, ekg: incomplete right bundle branch block, ekg: left bundle branch block, ekg: right bundle branch block, etc

The code I45.10 is not usually sufficient justification for admission to an acute care hospital when used as a principal diagnosis.

Short Description:Unspecified right bundle-branch block
Long Description:Unspecified right bundle-branch block

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code I45.10:

Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
  • Right bundle-branch block NOS

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code I45.10 are found in the index:

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10 Code Edits are applicable to this code:

  • Questionable admission codes - Some diagnoses are not usually sufficient justification for admission to an acute care hospital. For example, if a patient is given code R030 for elevated blood pressure reading, without diagnosis of hypertension, then the patient would have a questionable admission, since elevated blood pressure reading is not normally sufficient justification for admission to a hospital.


The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Bifascicular block
  • Bifascicular block on electrocardiogram
  • EKG: complete right bundle branch block
  • EKG: Incomplete right bundle branch block
  • EKG: left bundle branch block
  • EKG: right bundle branch block
  • Left anterior fascicular block
  • Left anterior fascicular block on electrocardiogram
  • Monofascicular block
  • Right bundle branch block
  • Right bundle branch block AND left anterior fascicular block
  • Right bundle branch block and left anterior fascicular block on electrocardiogram
  • Right bundle branch block with left bundle branch block
  • Right bundle branch block, anterior fascicular block AND incomplete posterior fascicular block

Clinical Information

  • BUNDLE BRANCH BLOCK-. a form of heart block in which the electrical stimulation of heart ventricles is interrupted at either one of the branches of bundle of his thus preventing the simultaneous depolarization of the two ventricles.
  • 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.

Diagnostic Related Groups

The ICD-10 code I45.10 is grouped in the following groups for version MS-DRG V37.0 What are Diagnostic Related Groups?
The Diagnostic Related Groups (DRGs) are a patient classification scheme which provides a means of relating the type of patients a hospital treats. The DRGs divides all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDC).
applicable from 10/01/2019 through 09/30/2020.


Convert I45.10 to ICD-9

  • 426.4 - Rt bundle branch block (Approximate Flag)

Code Classification

  • Diseases of the circulatory system (I00–I99)
    • Other forms of heart disease (I30-I52)
      • Other conduction disorders (I45)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients


An arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats too quickly, too slowly, or with an irregular pattern. When the heart beats faster than normal, it is called tachycardia. When the heart beats too slowly, it is called bradycardia. The most common type of arrhythmia is atrial fibrillation, which causes an irregular and fast heart beat.

Many factors can affect your heart's rhythm, such as having had a heart attack, smoking, congenital heart defects, and stress. Some substances or medicines may also cause arrhythmias.

Symptoms of arrhythmias include

  • Fast or slow heart beat
  • Skipping beats
  • Lightheadedness or dizziness
  • Chest pain
  • Shortness of breath
  • Sweating

Your doctor can run tests to find out if you have an arrhythmia. Treatment to restore a normal heart rhythm may include medicines, an implantable cardioverter-defibrillator (ICD) or pacemaker, or sometimes surgery.

NIH: National Heart, Lung, and Blood Institute

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