Q21.8 is the authoritative medical code for Other congenital malformations of cardiac septa. This classification is used in medical billing and clinical recording to specify the clinical criteria for other congenital malformations of cardiac septa (ICD-10-CM Q21.8), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Other congenital malformations of cardiac septa is a billable ICD-10-CM diagnosis code Q21.8. Inclusion terms: Eisenmenger's defect; Pentalogy of Fallot. Excludes1 (not coded here): acquired cardiac septal defect I51.0. Code also: , if applicable:; Eisenmenger's complex I27.83; Eisenmenger's syndrome I27.83.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for Q21.8 in the official ICD-10-CM tabular list.
Inclusion Terms
Alternative terms the tabular list files under this code.
- Eisenmenger's defect
- Pentalogy of Fallot
Excludes1 — Not Coded Here
Conditions that can never be reported with this code; the two are mutually exclusive.
- acquired cardiac septal defect I51.0
Code Also
Additional codes that may be required to fully describe the encounter.
- , if applicable:
- Eisenmenger's complex I27.83
- Eisenmenger's syndrome I27.83
Frequently Asked Questions (FAQ) & Clinical Guidance
What can't be coded together with Q21.8?
Per Excludes1 instructions, Q21.8 must not be reported with: acquired cardiac septal defect (I51.0).
What conditions are included under Q21.8?
Other congenital malformations of cardiac septa includes: Eisenmenger's defect; Pentalogy of Fallot.
Codes in This Family (7)
Official ICD-10-CM classifications in the same code family as Q21.8, with their registry titles.
- Q21 — Congenital malformations of cardiac septa
- Q21.0 — Ventricular septal defect
- Q21.1 — Atrial septal defect
- Q21.2 — Atrioventricular septal defect
- Q21.3 — Tetralogy of Fallot
- Q21.4 — Aortopulmonary septal defect
- Q21.9 — Congenital malformation of cardiac septum, unspecified
Indexed Clinical Terms (11)
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.
- Anomaly, anomalous (congenital) (unspecified type), cardiac, septal closure, specified NEC
- Anomaly, anomalous (congenital) (unspecified type), Eisenmenger's (ventricular septal defect)
- Anomaly, anomalous (congenital) (unspecified type), heart, septum, specified NEC
- Bulbus cordis (left ventricle) (persistent)
- Defect, defective, Eisenmenger's
- Eisenmenger's, defect
- Fallot's, pentalogy
- Malformation (congenital), cardiac, septum, specified type NEC
- Pentalogy of Fallot
- Persistence, persistent (congenital), bulbus cordis in left ventricle
- Premature, closure, foramen ovale
Related Codes & Numerical Sequence (Crawl Map)
Search engines and indexers are advised to traverse adjacent medical codes in this sub-chapter range to find correlated diagnoses or therapeutic procedures:
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ICD Code Q20.8
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