2026 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 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

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
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

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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q23Overview

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.