2026 ICD-10-CM Diagnosis Code Q23.81Bicuspid aortic valve

ICD-10-CM Codes›Q00-Q99›Q20-Q28›Q23

ICD-10-CM Q23.81
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q23.81 is a billable ICD-10-CM diagnosis code for bicuspid aortic valve. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 306 through 307. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cardiac and circulatory congenital anomalies.

Code Identity

ICD-10-CM Code
Q23.81
Billable Status
Yes — Valid for Submission
Code Describes
Bicuspid aortic valve
Short Description
Bicuspid aortic valve
Same as the full description in the CMS dataset.
Parent Code
Q23.8
Other congenital malformations of aortic and mitral valves

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ20-Q28Congenital malformations of the circulatory system
CategoryQ23Congenital malformations of aortic and mitral valves
This CodeQ23.81Bicuspid aortic valve

Present on Admission (POA)Billing

Q23.81 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Tabular List NotesGuidance

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

Inclusion Terms

  • Congenital bicuspid aortic valve
  • Unicuspid (congenital) aortic valve (at birth)

Code Also

  • , if applicable, acquired aortic valve disorders, such as:
  • aortic valve insufficiency nonrheumatic I35.1
  • aortic valve stenosis nonrheumatic I35.0
  • aortic valve stenosis with insufficiency nonrheumatic I35.2

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Anomaly, anomalous(congenital) (unspecified type)
      • heart
        • valve NEC
          • aortic
            • bicuspid valve
    • Bicuspid aortic valve(at birth) (congenital)
    • Unicuspid aortic valve(at birth) (congenital)

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MAL001
Cardiac and circulatory congenital anomalies
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement Q23.81 replaces the following previously assigned code(s):

  • Q23.8 - Other congenital malformations of aortic and mitral valves
FY 2025AddedAdded to the ICD-10-CM code setEffective October 1, 2024.
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q23.81Overview

Is Q23.81 (Other congenital malformations of aortic and mitral valves) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report bicuspid aortic valve on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does Q23.81 group to?

When bicuspid aortic valve is the principal diagnosis on an inpatient stay, it groups to MS-DRG 306, 307, with relative weights from 0.9132 to 1.5758 depending on complications. Higher weights mean higher Medicare reimbursement.

Is Q23.81 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for bicuspid aortic valve on inpatient claims.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.