ICD-10-CM › Q00-QA1 › Q20-Q28 › Q21.2 Atrioventricular septal defect › Q21.20

Valid for claims with a date of service in the current code year.

Valid FY2023 onwards.

What has happened to this code

Official coding rules

Published by CDC for FY2027. A rule attached to a category binds every code beneath it, so the rules inherited from this code's ancestors are shown with the code they come from.

Inherited from Q21 Congenital malformations of cardiac septa

Excludes1 - never coded here

• acquired cardiac septal defect (I51.0)

How CDC's index refers to this code

Wording from the official alphabetic index. Much of it appears nowhere in the code description, which is why a search for the everyday phrase so often finds nothing.

• Cleft
• Patent
• Window
• Missing
• Patulous
• Amputation
• Nonclosure
• Imperfect > fusion
• Vestige, vestigial
• Loss > organ or part
• Pervious, congenital
• Open, opening > false
• Absence > toe > with foot
• Deformity > atrial septal
• Fenestration, fenestrated
• Absence > congenital > septum
• Closure > defective or imperfect NEC
• Deformity > heart > septum > auricular
• Defect, defective > septal NOS > atrial
• Nonunion > organ or site, congenital NEC
• Open, opening > abnormal, organ or site, congenital
• Ostium > primum
• Single > atrium
• Canal > atrioventricular
• Defect, defective > ostium > primum
• Defect, defective > cushion, endocardial
• Endocardium, endocardial > cushion defect
• Persistence, persistent > ostium > primum
• Defect, defective > atrioventricular > canal
• Defect, defective > atrioventricular > septum
• Imperfect > closure > atrioventricular ostium
• Persistence, persistent > atrioventricular canal
• Defect, defective > atrial septal > ostium primum type
• Defect, defective > atrioventricular > septal > unspecified as to partial or complete

Codes in the same group

Code	Description	Status
Q21.21	Partial atrioventricular septal defect	Valid
Q21.22	Transitional atrioventricular septal defect	Valid
Q21.23	Complete atrioventricular septal defect	Valid