Q21.0 Ventricular septal defect

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis. Exempt from present-on-admission (POA) reporting.

Applicable to

• Roger's disease

Applies from Q21 Congenital malformations of cardiac septa

Excludes1 (never code together)

• acquired cardiac septal defect (I51.0)

Risk adjustment (HCC)

• RxHCC V08: HCC 191 — Ventricular Septal Defect and Major Congenital Heart Disorders

MS-DRG index

Defines the logic of DRG(s) 306-307 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 745.4 Ventricular septal defect (approximate)

Code annotations containing back-references to Q21.0

Back-references to Q21.0

• Code Also: I27.83 Eisenmenger's syndrome ("ventricular septal defect (Q21.0)")

Back-references to Q21

• Code Also: I27.21 Secondary pulmonary arterial hypertension ("congenital heart disease (Q20-Q28)")
• Type 2 Excludes: P29 Cardiovascular disorders originating in the perinatal period ("congenital malformations of the circulatory system (Q20-Q28)")
• Code Also: Q87.85 MED13L syndrome ("congenital malformations of cardiac septa (Q21.-)")
• Code Also: Z71.87 Encounter for pediatric-to-adult transition counseling ("congenital malformations of the circulatory system (Q20-Q28)")

Diagnosis Index entries for Q21.0

• Anomaly, anomalous (congenital) (unspecified type) › atrioventricular › septum
• Anomaly, anomalous (congenital) (unspecified type) › communication › left ventricle with right atrium
• Anomaly, anomalous (congenital) (unspecified type) › Gerbode
• Anomaly, anomalous (congenital) (unspecified type) › heart › septum › interventricular
• Anomaly, anomalous (congenital) (unspecified type) › heart › septum › ventricular
• Anomaly, anomalous (congenital) (unspecified type) › ventricular › septa
• Closure › interventricular septum, defective
• Defect, defective › bulbar septum
• Defect, defective › Gerbode
• Defect, defective › interventricular septal
• Defect, defective › septal (heart) NOS › ventricular
• Defect, defective › ventricular septal
• Deformity › heart (congenital) › septum › ventricular
• Disease, diseased › Roger's (congenital interventricular septal defect)
• Displacement, displaced › ventricular septum
• Fusion, fused (congenital) › ventricles, heart
• Gerbode defect
• Imperfect › closure (congenital) › interventricular ostium or septum
• Imperfect › closure (congenital) › ostium › interventricular
• Imperfect › closure (congenital) › septum › interventricular
• Imperfect › closure (congenital) › septum › ventricular
• Imperfect › septum, ventricular
• Maladie de Roger
• Patent › interventricular septum
• Roger's disease

Nearby codes

• Q21 Congenital malformations of cardiac septa
• Q21.0 Ventricular septal defect (this code)
• Q21.1 Atrial septal defect
• Q21.10 Atrial septal defect, unspecified
• Q21.11 Secundum atrial septal defect
• Q21.12 Patent foramen ovale
• Q21.13 Coronary sinus atrial septal defect