ICD-10-CM 2027
ICD-10 code for Unicuspid aortic valve
From the official ICD-10-CM alphabetic index entry “Unicuspid aortic valve (at birth) (congenital)”. Page updated September 29, 2026.
About coding Unicuspid aortic valve
The ICD-10-CM code for Unicuspid aortic valve is Q23.81 (Bicuspid aortic valve).
Within Q23.8 (other congenital malformations of aortic and mitral valves), Q23.81 is specifically for Bicuspid aortic valve. Related codes cover congenital mitral valve cleft leaflet (Q23.82) and other congenital malformations of aortic and mitral valves (Q23.88).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 306 (Cardiac Congenital and Valvular Disorders with MCC, relative weight 1.546) and DRG 307 (Cardiac Congenital and Valvular Disorders without MCC, relative weight 0.9148), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Unicuspid aortic valve ICD-10 codes
What is the ICD-10 code for Unicuspid aortic valve?
- Q23.81 — Bicuspid aortic valve.
Is Q23.81 billable?
- Yes. Q23.81 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Q23.81 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict Q23.81 as a principal diagnosis.
Is Q23.81 a CC or MCC?
- No. Q23.81 is neither a CC nor an MCC under MS-DRG v44.0.