2027 ICD-10-CM Diagnosis Code Q23Congenital malformations of aortic and mitral valves

ICD-10-CM Codes›Q00-Q99›Q20-Q28›Q23

ICD-10-CM Q23
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Q23 is a non-billable ICD-10-CM category code for congenital malformations of aortic and mitral valves, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Q23.0, Q23.1, Q23.2, and Q23.3.

Code Identity

ICD-10-CM Code
Q23
Billable Status
No — Non-Billable Category
Code Describes
Congenital malformations of aortic and mitral valves
Short Description
Congenital malformations of aortic and mitral valves
Same as the full description in the CMS dataset.
Chapter
Q20-Q28
Congenital malformations of the circulatory system

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ20-Q28Congenital malformations of the circulatory system
CategoryQ23Congenital malformations of aortic and mitral valves
This CodeQ23Congenital malformations of aortic and mitral valves

Specific Coding for Congenital malformations of aortic and mitral valvesOverview

Non-specific codes like Q23 require more characters. Use one of these billable codes instead:

  • Use Q23.0 for Congenital stenosis of aortic valve

  • Use Q23.1 for Congenital insufficiency of aortic valve

  • Use Q23.2 for Congenital mitral stenosis

  • Use Q23.3 for Congenital mitral insufficiency

  • Use Q23.4 for Hypoplastic left heart syndrome

  • Q23.8 for Other congenital malformations of aortic and mitral valves

  • Use Q23.81 for Bicuspid aortic valve

  • Use Q23.82 for Congenital mitral valve cleft leaflet

  • Use Q23.88 for Other congenital malformations of aortic and mitral valves

  • Use Q23.9 for Congenital malformation of aortic and mitral valves, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Q23: its own notes plus those printed at Chapter 17. 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 Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • inborn errors of metabolism (E70-E88)

Notes

General instructions on how these codes are used.

From Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • Codes from this chapter are not for use on maternal records

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Q23, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming Q23: its condition is not part of those codes, and both may be reported when the patient has both.

  • I08 Multiple valve diseases
    multiple valve disease specified as nonrheumatic (I34.-, I35.-, I36.-, I37.-, I38.-, Q22.-, Q23.-, Q24.8-)

Use Additional Code 1

These codes say to use an additional code from the note, and Q23 is one of the codes named.

  • Q87.88 CTNNB1 syndrome
    congenital heart malformations (Q20.0-Q24.9) names Q20.0-Q24.9, which includes this code

Patient EducationClinical

Congenital Heart Defects

Congenital heart defects (CHDs) are problems with the structure of the heart. "Congenital" means that that the problems are present at birth. These defects happen when a fetus's heart doesn't develop normally during pregnancy. Congenital heart defects are the most common type of birth defect.

The full article covers:

  • What are congenital heart defects?
  • What causes congenital heart defects?
  • Who is more likely to have a baby with a congenital heart defect?
  • What are the symptoms of congenital heart defects?
  • What other problems do congenital heart defects cause?
  • How are congenital heart defects diagnosed?
  • What are the treatments for congenital heart defects?

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Q23Overview

What is the ICD-10 code for congenital malformations of aortic and mitral valves?

Q23 is the ICD-10-CM category for congenital malformations of aortic and mitral valves, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is Q23 (Congenital malformations of aortic and mitral valves) a billable code?

No. This is a category header that groups the codes for congenital malformations of aortic and mitral valves, and headers cannot be submitted on claims. Claims for congenital malformations of aortic and mitral valves need a more specific code from this category, such as Q23.0, Q23.1, and Q23.2.